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There are relatively few running studies that have attempted to prospectively identify biomechanical risk factors associated with Achilles tendon (AT) injuries. Therefore, the aim was to prospectively determine potential running biomechanical risk factors associated with the development of AT injuries in recreational, healthy runners. At study entry, 108 participants completed a set of questionnaires. They underwent an analysis of their running biomechanics at self-selected running speed. The incidence of AT running-related injuries (RRI) was assessed after 1-year using a weekly questionnaire standardized for RRI. Potential biomechanical risk factors for the development of AT RRI injury were identified using multivariable logistic regression. Of the 103 participants, 25% of the sample (15 males and 11 females) reported an AT RRI on the right lower limb during the 1-year evaluation period. A more flexed knee at initial contact (odds ratio = 1.146, P =.034) and at the midstance phase (odds ratio = 1.143, P =.037) were significant predictors for developing AT RRI. The results suggested that a 1-degree increase in knee flexion at initial contact and midstance was associated with a 15% increase in the risk of an AT RRI, thus causing a limitation of training or a stoppage of running in runners. [ABSTRACT FROM AUTHOR]

Background: There are many adhesion barrier materials, cross-linked or non-cross-linked hyaluronic acid (HA), used during surgeries. Purpose: This study investigates the efficacy of cross-linked and non-cross-linked HA in preventing Achilles tendon adhesions. We hypothesized that non-cross-linked HA may be more effective than cross-linked HA in preventing Achilles tendon adhesions following injury and repair. Methods: Twenty male Sprague Dawley rats, totaling 40 legs, underwent Achilles tendon transection and repair. Following the surgery, they were treated simultaneously with cross-linked and non-cross-linked HA formulations. The rats were divided into four groups: a positive control group, a group treated with BMC non-cross-linked HA gel, a group treated with DEFEHERE cross-linked HA gel, and a group treated with ANIKA cross-linked HA gel. Four weeks after surgery, macroscopic evaluation of peritendinous adhesion and histological analysis were conducted to assess the effectiveness of the treatments. Results: Non-cross-linked BMC HA demonstrated superior efficacy in preventing tendon adhesions compared to cross-linked HA and control groups. Histological analysis confirmed reduced adhesion severity in the non-cross-linked HA group (P < 0.05). The findings support the potential of non-cross-linked HA as a treatment to inhibit tendon adhesions. Further research, including clinical trials, is warranted to validate these results in human subjects. Conclusions: Non-cross-linked BMC HA had significantly lower tendon adhesions parameters and better healing scores in histological analysis than cross-linked HA and control group did. Non-cross-linked HA holds promise as a potential treatment to inhibit the formation of such adhesions. [ABSTRACT FROM AUTHOR]

Background Given rising youth sport participation, 8 to 10-year-olds increasingly display comparable lower-extremity injury incidence to 11 to 17-year-olds and require effective return to sport criteria. One such criterion which quantifies dynamic stability is the Y-Balance Test (YBT), though it has not been validated in children under age 11. Hypothesis/Purpose The purpose of this study was to examine the performance of 8 to 10-year-old patients on the YBT after lower-extremity injury and determine how these results compare to larger samples of age-grouped athletes within the validated 11 to 17-year-old range. It was hypothesized that 8 to 10-year-olds would display different normalized YBT distances compared to 11 to 17-year-olds. Study Design Cross-sectional Study. Methods Patients (N=1093) aged 8 to 17 who presented to a pediatric sports medicine practice with a lower-extremity injury and completed the YBT between December 2015-May 2021 were included. Anterior, posteromedial, and posterolateral YBT scores were collected at return-to-sport for affected and unaffected limbs. Scores were normalized to limb length, and composite scores were created. Between-limb differences were calculated in groups of ages 8-10, 11-12, 13-14, and 15-17. Groups were also evaluated for differences by sex. Results A rise in performance was observed in unaffected limb anterior reach from ages 8 to 10 years to 11 to 12 years followed by a subsequent significant decrease at older ages (p<0.001). Affected limb anterior reach differed between the youngest group and two oldest groups (p=0.004). Anterior and composite difference were significantly different between the oldest three groups (p=0.014 anterior; p=0.024 composite). No differences were observed between sexes in 8 to 10-year-olds, though 11 to 12-year-old females reached further during all eight distances. In the older three groups, males generally displayed greater between-limb differences. Conclusion YBT scores, specifically anterior reach, demonstrated inconsistency by age and sex across a large adolescent cohort. Existing return-to-sport standards should not be used with younger athletes, and individual validation is required. Level of Evidence Level III [ABSTRACT FROM AUTHOR]

Background: Achilles tendon is vital in maintaining the stability and function of ankle joint. It is quite difficult to achieve the structural and functional repair of Achilles tendon in tissue engineering. Methods: A tissue-engineered tendon micro-tissue was prepared using rat tail tendon extracellular matrix (TECM) combined with rat adipose stem cells (ADSCs) to repair Achilles tendon injuries. The TECM was prepared by repeated freezing and thawing. The in vitro characteristics of TECM and its effect on ADSCs proliferation were detected. This tissue-engineered tendon micro-tissue for Achilles tendon repair in vivo was evaluated based on general characteristics, gait analysis, ultrasound findings, histological analysis, and biomechanical testing. Results: The results showed that the TECM scaffold had good biocompatibility for ADSCs. At 2 weeks post-surgery, collagen types I and III and tenomodulin expression were higher, and vascular endothelial growth factor expression was lower in the micro-tissue group than other groups. At 4 and 8 weeks post-surgery, the results of histological analysis and ultrasound findings showed that the repaired tendon tissue was smooth and lustrous, and was arranged regularly and evenly in the micro-tissue group. Gait analysis confirmed that better motor function recovery was noted in micro-tissue group than other groups. In addition, the mechanical properties of the repaired tendon tissue in micro-tissue group were better than other groups. Conclusion: Tissue-engineered tendon micro-tissue fabricated by TECM and ADSCs has good biocompatibility and can promote structural and functional repair of tendon in vivo. This composite biomaterial has broad application prospects in tissue engineering. [ABSTRACT FROM AUTHOR]

Objectives: Acute rupture of achilles tendon is a commonly occurring injury affecting mostly the young individuals involved in sports activities. Operative management is most often employed to treat such injuries. This study was aimed to evaluate the functional outcome in patients with acute tendo achilles tear managed by open repair using a suture anchor. Methods: This was a prospective study conducted between September 2018 to August 2020 on patients who underwent suture anchor repair for acute tendo achilles tear. All patients were followed up for at least 9 months. The patients were clinically evaluated and AOFAS score was used to assess their functional outcome. Results: In a total of 38 patients, 28 (73.7%) patients showed Excellent and 7 (18.4%) patients had Good results whereas 1 (2.6%) had Fair and 2 (5.3%) patients demonstrated Poor surgical result at the final follow-up. 89.5% patients did not have any complication. The average AOFAS score was 90.97 ± 10.24. Conclusion: Operative treatment with suture anchor in acute tendo achilles tear has a high success rate, quick recovery after surgery, lower rate of complications, faster return to daily activities, excellent aesthetic and comparable functional results and is also a safe, simple and accepted surgical technique. [ABSTRACT FROM AUTHOR]

Tendons are connective tissues with limited healing potential which results in permanently impaired function. Although direct mechanical testing of tendon remains the gold standard for functional analyses, this assay is terminal and tracking healing over time requires the use of many animals. An alternative method for quantifying tendon function is gait analysis, which is non-terminal and enables longitudinal tracking of the same animal. To date, commercial systems used to analyze gait are mostly applied to study neurobehavior, and applications for tendon research has been limited. Since these systems typically output many parameters, it is challenging to know which parameter is most relevant for a specific injury model. To address this challenge, we used a well-established rodent locomotion system (CatWalk XT) to measure longitudinal gait parameters in sham and Achilles tendon-injured mice (from PREOP to 56 days post-injury) and identified relevant and reproducible parameters specifically associated with Achilles tendon injury and healing. Micro computed tomography (micro- CT) and mechanical testing also confirmed persistent tendon impairment in the same animals at the terminal timepoint. Collectively, our results provide a useful reference and recommendation of CatWalk gait parameters and the control comparisons that both conserve the use of animals while maintaining high reproducibility standards for Achilles tendon injury studies. [ABSTRACT FROM AUTHOR]

• The incidence of Achilles tendinopathy was 4.2% during 20 weeks of follow-up among recreational runners. About two-thirds of the onsets were categorized as insertional Achilles tendinopathy, and about one-third were midportion subtype. • No significant association between training load and onset of Achilles tendinopathy was found so far. Future studies should apply more advanced serial measures of training load to identify whether overuse is a risk factor for Achilles tendinopathy. • The observed different risk factors between midportion and insertional Achilles tendinopathy were limited. It is questionable whether there is solid ground to regard them as subcategories from a clinical perspective. Achilles tendinopathy (AT) is a common problem among runners. There is only limited evidence for risk factors for AT, and most studies have not defined the AT subcategories. No study has compared the incidence and risk factors between insertional AT and midportion AT, though they are considered distinct. This study aimed to assess incidence and risk factors of AT based on data from a large prospective cohort. The secondary aim was to explore differences in risk factors between insertional and midportion AT. Participants were recruited from among registered runners at registration for running events. Questionnaires were completed at baseline, 1 month before the event, 1 week before the event, and 1 month after the event. Information concerning demographics, training load, registered events, and running-related injuries were collected at baseline. The follow-up questionnaires collected information about new injuries. A pain map was used to diagnose midportion and insertional AT. The primary outcome was the incidence of AT. Multivariable logistic regression analysis was applied to identify risk factors for the onset. We included 3379 participants with a mean follow-up of 20.4 weeks. The incidence of AT was 4.2%. The proportion of insertional AT was 27.7% and of midportion AT was 63.8%; the remaining proportion was a combined type of insertional and midportion AT. Men had a significantly higher incidence (5%, 95% confidence interval (95%CI): 4.1%–6.0%) than women (2.8%, 95%CI: 2.0%–3.8%). AT in the past 12 months was the most predominant risk factor for new-onset AT (odds ratio (OR) = 6.47, 95%CI: 4.27 –9.81). This was similar for both subcategories of AT (insertional: OR = 5.45, 95%CI: 2.51–11.81; midportion: OR = 6.96, 95%CI: 4.24–11.40). Participants registering for an event with a distance of 10/10.55 km were less likely to develop a new-onset AT (OR = 0.59, 95%CI: 0.36–0.97) or midportion AT (OR = 0.47, 95%CI: 0.23 –0.93). Higher age had a significant negative association with insertional AT (OR = 0.97, 95%CI: 0.94–1.00). The incidence of new-onset AT among recreational runners was 4.2%. The proportion of insertional and midportion AT was 27.7% and 63.8%, respectively. AT in the past 12 months was the predominant risk factor for the onset of AT. Risk factors varied between insertional and midportion AT, but we could not identify clinically relevant differences between the 2 subtypes. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Achilles tendon injuries often generate substantial discussion in the mainstream media. The Altmetric Attention Score (AAS) measures the online dialogue pertaining to Achilles tendon research that occurs outside scientific journals, which traditional citation-based metrics fail to capture. Purpose: To characterize the top 100 most-cited Achilles tendon articles and compare them with the 100 Achilles tendon articles with the highest AAS. A secondary goal was to gain an improved understanding of the online dissemination and interpretation of Achilles tendon research through this comparison. Study Design: Cross-sectional study. Methods: The Web of Science Clarivate database was queried to isolate the 100 most-cited Achilles tendon articles, and the Altmetric database was queried to identify the Achilles tendon articles with the top 100 AAS values. Data elements were extracted for each article including study type, study topic, and geographic origin. Results: The Web of Science Clarivate database search yielded 10,890 articles published between 1970 and 2021. The 100 most-cited articles were published in 35 journals, with the American Journal of Sports Medicine being the most prevalent. The mean (±SD) number of citations was 214.5 ± 86.47. The most prevalent study type was laboratory (28.0%). The most prevalent study topic was treatment (41.0%). Of these articles, 72.0% were European. The Altmetric database search yielded 3810 articles published between 1957 and 2021. The AAS of the top 100 articles ranged from 37 to 476 with a mean of 98.17 ± 85.53. The selected articles were published in 39 journals, with the British Journal of Sports Medicine being the most prevalent. The most prevalent study type was randomized controlled trial (25.0%). The most common study topic was treatment (40.0%). Of these articles, 46.0% were European. Conclusion: Our findings suggest that, although the scientific community remains committed to high-impact journals with articles backed by high citation numbers, there is an increasing opportunity to consume Achilles tendon literature through social media. [ABSTRACT FROM AUTHOR]

Background. Tendon injuries are responsible for a crescent number of people retirement around the world. Recently, cell-based therapies has been shown to be effective for the treatment of tendon injures. Objective. We aimed to evaluate the effect of local treatment with conditioned medium produced by tenocytes cell cultures on the histological and functional recovery in tenotomized mice. Methods. The tendon cells were cultured for conditioning culture medium that will be used as treatment. The animals were subjected to right Aquilles tenotomy and treated with saline solution (SAL), DMEM (DMEM) and DMEM conditioned in tenocytes cultures (CM) and compared to the control group (CTRL). For histological analysis, tissues were stained with HE. Tendon functionality was measured using the Achilles Functional Index (AFI) and mechanical sensitivity through the paw withdrawal threshold (PWT) using the Von Frey test. Analyzes were performed at 7-, 14- and 21-days post-injury (dpi). Statistics were performed by ANOVA-2 followed by Tukey's post-test, p < 0.01. Results. In the histological analysis, the CM group showed better tissue organization when compared to SAL and DMEM groups. The CM group showed improvement in the PWT at 7° and 14° dpi (2.24 ± 1.15; 2.66 ± 1.06) compared to the DMEM (0.15 ± 0.07; 0 .45 ± 0.76 p < 0.01) and SAL (0.13 ± 1.15; 0.77 ± 0.95 p < 0.01). The CM group showed functional improvement at 7° and 14° dpi (-40.4 ± 12.6; -36.6 ± 10.4) compared to the DMEM (-76.5 ± 11.7; -71, 6 ± 7.9, p < 0.01) and SAL (-88.8 ± 15; -71.4 ± 12.6 p < 0.01). Conclusions. We conclude that treatment with tenocytes conditioned medium accelerates tendon recovery, promoting improvement in mechanical sensitivity, functionality and tissue organization in the proposed injury model. [ABSTRACT FROM AUTHOR]

The therapeutic role of tendon stem cells (TSCs) in tendon-related injuries has been well documented. Small extracellular vesicles (sEVs) are being increasingly used as new biotherapeutic agents for various diseases. Therefore, the potential function of TSC-sEVs in tendon injury repair warrants further investigation. In this study, we explored the effects of TSC-sEVs on TSC proliferation, migration, and differentiation in vitro in an autocrine manner. We further used a novel exosomal topical treatment with TSC-sEVs loaded with gelatin methacryloyl (GelMA) hydrogel in vivo ; we mixed sufficient amounts of TSC-sEVs with GelMA hydrogel to cover the damaged molded Achilles tendon tissue and then exposed them to UV irradiation for coagulation. GelMA loading ensured that TSC-sEVs were slowly released at the injury site over a long period, thereby achieving their full local therapeutic effects. Treatment with TSC-sEVs loaded with GelMA significantly improved the histological score of the regenerated tendon by increasing the tendon expression while inhibiting the formation of excessive ossification and improving the mechanical properties of the tissue. Moreover, miRNA sequencing in TSC-sEVs, TSCs, and TSCs receiving sEVs revealed that TSC-sEVs altered the miRNA expression profile of TSCs, with increased expression of miR-145-3p. In conclusion, our study demonstrates that TSC-sEVs can play a key role in treating tendon injuries and that loading them with GelMA can enhance their effect in vivo. Moreover, miR-145-3p has a major functional role in the effect of TSC-sEVs. This study offers new therapeutic ideas for the local treatment of Achilles tendon injuries using sEVs. In this study, we demonstrated that TSC-sEVs play a key role in treating tendon injuries and that loading them with GelMA hydrogel can act as a fixation and slow release in vivo. Moreover, it identifies the major functional role of miR-145-3p in the effect of TSCs that were identified and validated by miRNA sequencing. Our study provides a basis for further research on GelMA slow-release assays that have potential clinical applications. It offers new therapeutic ideas for the local treatment of Achilles tendon injuries using TSC-sEVs. [Display omitted] [ABSTRACT FROM AUTHOR]

The plantar muscle is fusiform, attaching to the calcaneus, starting behind the knee. Plantaris muscle formation has been reported in humans at a rate approaching 90%. It is frequently preferred for tendon grafting and tendon transfer in hand surgery and Achilles tendon injuries. In this study, our goal is to investigate the frequency of the presence of the plantar muscle in the Somali population. We retrospectively analyzed 607 knee MRI scans performed at Recep Tayyip Erdoğan Training and Research Hospital in Mogadishu between January 2019 and March 2022. The clinical and demographic characteristics of the patients were recorded. Patients with muscle trauma and previous surgery involving muscles, proximal tibia fracture surgery, and soft tissue tumors were dropped out of the study. 469 (77.3%) of these patients were male and 138 (22.7%) were female.182 (72%) of the male patients with right MRI saw plantaris while 68 (28%) did not. While plantaris was seen in 183 (83.5%) of the male patients who underwent left-sided MRI, plantaris was not seen in 30 (16.5%). Plantaris was seen in 62 (79.5%) of the female patients who had right-sided MRI, while plantaris was not seen in 16 (20.5%). Left plantar was present in 55 (91.7%) and absent in 5 (8.3%) female patients who underwent left-sided MRI. Since the plantaris muscle is used as a tendon graft, pre-op evaluation of its presence is important in terms of surgery and can change the surgical procedure. The presence of the plantar tendon can be revealed by using knee MRI in the Somali population living in the African continent. [ABSTRACT FROM AUTHOR]

Background. L-carnitine (LC), which has anti-inflammatory and antioxidant effect, is especially consumed by sportmans to increase muscle mass recently. Therefore, the functional, histopathological effects of LC on experimental Achilles tendon injury were investigated in this study. Methods. Forty male Wistar Albino rats were randomly divided into four groups (n = 10). A tendon injury model was created by clamping the left Achilles tendon of all rats except the control group. Tendon Injury Group (TIG) and the Control group did not receive LC treatment. LC (100 mg/kg/day, intraperitoneally) was started to administer one week before the injury model in pre-LC group and the same day of injury in post-LC group following the establishment of model for four weeks. After the tendon injury and at the end of the experiment, rats in all groups were subjected to a Gait test (GT) twice. On the 30th day of injury, the rats were sacrificed, and left Achilles tendons were dissected for histopathological analysis. Results. Initial GT data were significantly different between the control and other groups (p < 0.001). The final GT data were significantly different only between the Control and TIG (p = 0.002). Histopathological examination revealed that neovascularization, fibroblastic activity, and collagen fibril sequencing parameters were found to be significantly different amongst the TIG and pre-LC group, and post-LC group (p < 0.05). Conclusions. LC contributes to the tendon healing by histopathologically and functionally. [ABSTRACT FROM AUTHOR]

Achilles' tendon (AT) injuries such as ruptures and tendinopathies have experienced a dramatic rise in the mid- to older-aged population. Given that the AT plays a key role at all stages of locomotion, unsuccessful rehabilitation after injury often leads to long-term, deleterious health consequences. Understanding healthy in vivo strains as well as the complex muscle–tendon unit interactions will improve access to the underlying aetiology of injuries and how their functionality can be effectively restored post-injury. The goals of this survey of the literature with a systematic search were to provide a benchmark of healthy AT strains measured in vivo during functional activities and identify the sources of variability observed in the results. Two databases were searched, and all articles that provided measured in vivo peak strains or the change in strain with respect to time were included. In total, 107 articles that reported subjects over the age of 18 years with no prior AT injury and measured while performing functional activities such as voluntary contractions, walking, running, jumping, or jump landing were included in this review. In general, unclear anatomical definitions of the sub-tendon and aponeurosis structures have led to considerable confusion in the literature. MRI, ultrasound, and motion capture were the predominant approaches, sometimes coupled with modelling. The measured peak strains increased from 4% to over 10% from contractions, to walking, running, and jumping, in that order. Importantly, measured AT strains were heavily dependent on measurement location, measurement method, measurement protocol, individual AT geometry, and mechanical properties, as well as instantaneous kinematics and kinetics of the studied activity. Through a comprehensive review of approaches and results, this survey of the literature therefore converges to a united terminology of the structures and their common underlying characteristics and presents the state-of-knowledge on their functional strain patterns. [ABSTRACT FROM AUTHOR]

Background: Rupture of the Achilles tendon is a considerable cause of morbidity with reduced function following injury. Randomized studies have so far failed to show a difference in outcome between operative and nonoperative management of Achilles tendon rupture, provided that no re-rupture occurs. Percutaneous Achilles repair has been suggested to result in superior patient satisfaction compared with open repair in patients with an acute Achilles tendon rupture. Aim and Objectives: To assess and evaluate the functional outcome after percutaneous repair in patients of the acute and closed Achilles tendon ruptures. Materials and Methods: It was a prospective study conducted on patients diagnosed as having rupture of the Achilles tendon. A total of 25 patients with mean age of 44.4 (range 19–65) years were taken, who underwent percutaneous Achilles tendon repair. Results: The number of patients who reported excellent or good scores (ATRS > 80) at 3, 6 and 12 months were 0%, 16% and 100%, respectively. The mean AOFAS hind foot score at 3-, 6- and 12-month follow-ups was 77.9 ± 4.3, 92.04 ± 2.4 and 96.16.32 ± 1.1, respectively. The number of patients who reported excellent or good scores (AOFAS > 74) at 3, 6 and 12 months were 76%, 100% and 100%, respectively. Most of the patients in our study showed no complications, and only 2 (8%) of patients had the features of sural nerve injury which was resolved in the subsequent follow-ups. Conclusion: Percutaneous repair of the Achilles tendon is an effective procedure which gives excellent functional outcome with very few complications. The percutaneous technique gives an additional advantage of less operative time, no wound complications, less damage to the soft tissues, and improved cosmesis as compared to the open repair. [ABSTRACT FROM AUTHOR]

The rate of lower extremity musculoskeletal injury (LE MSK) is elevated after concussion; however, the underlying mechanism has not been elucidated. Physical characteristics have been investigated despite poorer mental health being a common postconcussion complaint and linked to MSKs. To evaluate the role of mental health as a predictor of postconcussion LE MSK. Case-control study. Intercollegiate athletic training facility. A total of 67 National Collegiate Athletic Association Division I student-athletes (n = 39 females) who had been diagnosed with a sport-related concussion. The Brief Symptom Inventory-18, Hospital Anxiety and Depression Scale, and Satisfaction With Life Scale (SWLS) measures were completed at baseline (preseason) and on the day participants were cleared for unrestricted return to play (RTP) after a concussion. Two binary logistic regressions were used to predict postconcussion LE MSK within a year, one for the baseline time point and the second for the RTP time point. A 2 (group: LE MSK, no LE MSK)-by-2 (time: baseline, RTP) repeated-measures analysis of variance compared performance between baseline and RTP. Subsequent LE MSKs were sustained by 44 participants (65.7%). The only significant predictor of postconcussion LE MSK was the SWLS score at RTP, with Exp(B) = 0.64, indicating that an increased (improved) SWLS score was associated with a lower LE MSK rate. No significant interactions were present between mental health measures and subsequent MSK (P values =.105–.885). Limited associations were evident between postconcussion LE MSK and scores on commonly used measures of anxiety, depression, and satisfaction with life. Reported increased satisfaction with life was associated with a decreased injury risk, which warrants further attention. Our results suggest that these measures of anxiety, depression, and satisfaction with life have limited value in assisting sports medicine clinicians with determining which student-athletes are at elevated risk of postconcussion LE MSK. [ABSTRACT FROM AUTHOR]

Background: Achilles tendon injuries represent one of the most common reasons for referral to orthopaedic surgeons. Purpose: To outline the characteristics, examine trends in publication, and evaluate the correlation between citations and study quality of the 50 most cited articles on Achilles tendon injury. Study Design: Cross-sectional study. Methods: After searching the Web of Science for articles published in orthopaedic journals, we identified the 50 most cited articles on Achilles tendon injury and abstracted their characteristics. Risk of bias was assessed using the modified Coleman Methodology Score (mCMS). Multiple bivariate analyses (Pearson or Spearman correlation coefficient) were used to evaluate the association among number of citations, citation rate (citations/year), 2020 journal impact factor (JIF), year of publication, level of evidence (LoE), study type (tendon rupture or chronic tendinopathy), sample size, and mCMS. Results: The top 50 articles were cited 12,194 times. Each article had a mean ± SD 244 ± 88.8 citations (range, 157-657) and a citation rate of 12.6 ± 5.4 per year (range, 3-28). A total of 35 studies (70%) were published between 2000 and 2010. The citation rate of the 16 most recent studies was almost double that of the 16 oldest studies (17.5 vs 9.9; P <.001). Nineteen studies (49%) were classified as having poor quality (mCMS <50 points). The mean JIF of the 9 journals that published the studies was 5.1. The citation rate correlated with the number of citations (r = 0.56; P <.001), publication year (r = 0.60; P <.001), and LoE (r = –0.44; P =.005). The publication year correlated with the LoE (r = –0.40; P =.01). Study quality in terms of mCMS correlated with the JIF (r = 0.35; P =.03) and LoE (r = –0.48; P =.003) but not the citation rate (P =.15). Conclusion: The mean LoE and the citation rate of the most cited articles on Achilles tendon injury both significantly increased over time. Although the JIF was positively correlated with study quality, almost half of the studies had poor-quality methodology. [ABSTRACT FROM AUTHOR]

Introduction Military training that increases physical stress on musculoskeletal morphology also increases the risk of orthopedic injuries. Somatosensory prevention programs that reduce stress and improve functionality could be beneficial for better organization of tendon structure. The aim of this study was to investigate the impact of a somatosensory prevention exercise on the tendon structure (percentage of echo-type fibers; A-P and M-L diameters and cross-sectional area) of the Achilles tendon and patellar tendon among combat soldiers. Materials and Methods These tendons of male Infantry soldiers aged 18-21 were screened before and after a 14-week training course. The intervention group, who performed preventative exercises, included 108 soldiers (BMI = 23.85 ± 2.76), while the control group, who participated in the same military course without these exercises, included 98 soldiers (BMI = 24.26 ± 4.03). Ultrasound scanning for tendon structure included percent of echo-type I-IV fibers, A-P diameter, M-L diameter, and cross-sectional area parameters. Results Time by group interaction was found for echo-type I and II in both tendons. No significant differences were found between the two groups in the pretesting percentage of echo-type IV fibers of the Achilles tendon (P  = .522), in echo-type III fibers of the Achilles tendon (P  = .833), and echo-type IV fibers of the patellar tendon (P  = .162). Greater pre-post differences in echo-type III and IV fibers were found in the control group compared with the intervention group for both the Achilles tendon (P  = .021, P  = .002) and the patellar tendon (P  < .001, P  < .001). Conclusion Increased damaged fibers (echo-type III and IV) of both tendons were found among the control group, yet not among soldiers who performed prevention exercises. [ABSTRACT FROM AUTHOR]

Severe flexible flatfeet with triceps surae complex shortening are prognostically unfavorable in early childhood and may compromise normal foot development. This retrospective, IRB-approved study included 20 children (38 feet) under 6 years with severe flexible flatfeet and triceps surae complex shortening. Treatment included minimally invasive percutaneous achilles tendon lengthening followed by a 4-week cast fixation and corrective orthotic therapy under talo-navicular reposition for at least 6-months. Preoperative weightbearing x-rays and at the last available follow-up included anteroposterior talus-first metatarsal angle and lateral talus pitch, Meary's and talocalcaneal angle and were compared to reference values. ROM, surgeon-rated clinical outcomes and complications/re-interventions were evaluated. Age at surgery was 3.7 years (1.3–5.9 y) and follow-up time was 4.3 years (1.1–8.9 y). No complications occurred. Clinical outcome was good (68 %) to very good (26 %). Ratio of normal angles increased significantly for three angles. Dorsiflexion ROM improved from −5.0 ± 6.8° at baseline to 15.7 ± 7.6°. With significant improvements in clinical and radiographic outcomes, minimal-invasive percutaneous Achilles tendon lengthening followed by orthotic therapy seems to be a valuable treatment option for selected preschool-aged patients with severe, flexible flatfeet with significantly shortened triceps surae. IV [ABSTRACT FROM AUTHOR]

Individual treatment selection has been proposed as the key to optimized treatment. The purpose was to investigate if treatment selection using the individualized treatment algorithm Copenhagen Achilles Rupture Treatment Algorithm (CARTA) differs between patients treated as usual regarding gait dynamics and tendon elongation. The patients were randomized to one of three parallel groups: 1) intervention group: participants treated according to CARTA, 2) control group: participants treated non-operatively, 3) control group: participants treated operatively. The primary outcome was ankle peak power during push off during walking at 12 months. 156 patients were assessed for eligibility. 21 were allocated to the intervention group, and 20 and 19 to the control groups. The results indicated no statistically significant differences between the intervention group and the control groups. Individualized treatment selection based on CARTA did not demonstrate less affected gait dynamics or less tendon elongation than patients treated as usual. [ABSTRACT FROM AUTHOR]

Background and purpose -- Data on incidence and on trends in treatment of hamstring injuries, including proximal hamstring tendon avulsions (PHA), is limited. We aimed to investigate the incidence, trends in operative treatment, age, and sex distribution of hamstring injuries in Sweden between 2001 and 2020. Patients and methods -- We obtained data recorded in the National Patient Register between 2001 and 2020 on patients between 18 and 90 years of age, with the ICD-10 code S76.3, to calculate the incidence of patients treated operatively for hamstring injuries in Sweden. Patients with the NOMESCO classification NFL49 were considered as having been treated operatively. Data on quadriceps and Achilles tendon injuries were obtained for comparison. To calculate incidences, adult population data for every year were obtained from the Statistics Sweden website. Results -- The incidence of patients diagnosed with hamstring injuries increased from 2.2 to 7.3 per 100,000 person-years. There was a rising trend of surgical treatment per diagnosed case from 3.0% to 14.2%. Patients diagnosed in units with the highest experience of surgical treatment of hamstring injuries tended to be operated on more often (22.2%) than patients diagnosed in units with limited experience (5.1%), although the fraction of operated patients was increasing in both groups. Conclusion -- Between 2001 and 2020 there was an increase in the proportion of operatively treated hamstring injuries. [ABSTRACT FROM AUTHOR]

Calcaneus fractures make up only 2% of all fractures, and tongue-type calcaneus fractures represent 25-40% of all calcaneus fractures. While rare, tongue-type calcaneus fractures can put the superficial soft tissue at risk for necrosis and other complications, creating a surgical emergency. This case report describes the care of a patient who presented to a remote island critical-access emergency room after a fall from height. He described severe, sharp pain in the heel and was found to have tenting and blanching of the overlying skin near the injury. These findings suggested the soft tissues were at high risk for necrosis if not treated immediately. An X-ray confirmed a tongue-type calcaneus fracture. The patient was splinted in plantar flexion and transported by helicopter to a mainland hospital capable of performing the appropriate surgical reduction. The patient underwent open reduction internal fixation of the calcaneus, relieving pressure on the skin. He tolerated the procedure well, and there were no complications. He was discharged the day after surgery with outpatient follow-up. His case was prolonged and required multiple procedures to ultimately achieve appropriate healing. This case illustrates the importance of recognizing fractures presenting with skin involvement since surgical emergencies require prompt intervention to reduce the risk of serious complications such as open fracture from skin breakdown, poor healing, and a slow return to normal activities. It also emphasizes the importance of advocating for expedient patient care to increase the odds of a good outcome and ensure patients are given high-quality care. Topics: Calcaneus fracture, tongue-type calcaneus fracture, fall from height, axial loading, fracture complications, case report. [ABSTRACT FROM AUTHOR]

Background: Deficits in calf muscle function and heel-rise performance are common after an Achilles tendon rupture (ATR) and are related to tendon elongation and calf muscle atrophy. Whether early functional mobilization (EFM) can improve calf muscle function compared with standard treatment (ST) with 2 weeks of immobilization and unloading in a plaster cast is unknown. Hypothesis: EFM would lead to superior recovery of heel-rise performance, as demonstrated by more symmetrical side-to-side ankle and knee joint kinematics, compared with ST. Study Design: Cohort study; Level of evidence, 2. Methods: In total, 47 patients with an ATR were prospectively included and treated with open surgical repair and randomized 2:1 postoperatively to either EFM or ST. Overall, 29 patients were treated with a dynamic orthosis (EFM), and 18 underwent ST. At 8 weeks and 6 months after ATR repair, 3-dimensional motion analysis of heel-rise performance was conducted. At 6 months, tendon length and muscle volume were assessed with ultrasound imaging, calf muscle function with the heel-rise test, and patient-reported outcomes with the Achilles tendon Total Rupture Score. Results: At 8 weeks and 6 months, there were no significant group differences between the EFM and ST groups in heel-rise performance, but significant side-to-side differences in ankle and knee kinematics were detected. At 8 weeks and 6 months, both the EFM and ST groups showed a significantly decreased peak ankle plantarflexion angle and increased knee flexion angle on the injured limb compared with the uninjured limb during bilateral heel raises. Linear regression demonstrated that greater atrophy of the medial gastrocnemius muscle (P =.008) and higher body weight (P <.001) were predictors of a decreased maximum peak ankle plantarflexion angle on the injured limb at 6 months. Conclusion: EFM after an ATR repair did not lead to superior recovery of calf muscle function, as assessed by heel-rise performance, compared with ST. Increased knee flexion seemed to be a compensatory strategy for decreased ankle plantarflexion. Medial gastrocnemius atrophy and increased body weight were additional factors associated with a decreased ankle plantarflexion angle. Registration: NCT02318472 (ClinicalTrials.gov identifier). [ABSTRACT FROM AUTHOR]

Orthoses are an important part of both conservative and operative treatment of acute Achilles tendon rupture as they can be used to position the foot in equinus and protect the torn tendon from strain in the healing phase. The aim of the study was to test four different orthoses ability to position the foot in equinus. The study was performed as a cross-sectional study. 15 healthy study participants underwent radiographic examination with 11 true lateral radiographs of the right ankle and foot, one with the ankle joint in neutral position; one of a circular equinus cast (CEC); three of an adjustable equinus boot (AEB) with the foot in 30°, 15°, and 0° of plantar flexion, respectively; three of a fixed angle orthosis with 1, 2, and 3 wedges with a plateau (WWP); and three of a fixed angle orthosis with 1, 2, and 3 wedges without plateau (WWOP). The primary outcome was the Achilles Relief Distance (ARD). Secondary outcomes were the tibiocalcaneal angle (TCA), the tibiotalar angle (TTA), and the tibio- 1st metatarsal angle (1MTP). All measurements were performed by a radiologist. The mean (SD) ARD was 11 mm (7) in CEC, 23 mm (6) with 3 WWP, 11 mm (5) with 3 WWOP, and 15 mm (5) using AEB in 30° of plantarflexion. The mean (SD) TCA was 86° (7,8) in CEC, 76° (7,3) with 3 WWP, 90° (6,9) with 3 WWOP, and 84° (6,6) using the AEB in 30° of plantarflexion. CEC, AEB, and WWOP showed statistically significantly larger plantarflexion than WWP. CEC, AEB and WWOP produced significantly greater plantarflexion compared to WWP. [ABSTRACT FROM AUTHOR]

Background: The preseason is a crucial time period for professional athletes to prepare for the upcoming season. However, due to the coronavirus 2019 (COVID-19) pandemic, the 2020 National Football League (NFL) preseason was canceled. As the regular season progressed, an increased number of injuries became apparent. Purpose/Hypothesis: The purpose of this study was to compare injury rates between the 2019 and 2020 NFL regular seasons after the canceled 2020 preseason. It was hypothesized that injury rates in the 2020 season would be the same or higher compared with 2019. Study Design: Descriptive epidemiology study. Methods: A public database of all 32 NFL teams was used to examine the movement of all players to injured reserve status as well as every player who missed a regular-season game due to injury for both the 2019 and the 2020 NFL regular seasons. Data collection consisted of tallying the total number of reported musculoskeletal injuries for each team. Comparisons of injury rates between the 2 seasons were made using a Wilcoxon signed-rank statistical analysis. Results: The total number of musculoskeletal injuries was 632 for the 2019 regular season and 765 for the 2020 regular season (P =.0324). Compared with 2019, statistically significant increases in injury rates in 2020 were seen for calf or Achilles tendon strain (17 vs 39; P =.009), groin injury (25 vs 46; P =.018), and anterior cruciate ligament tear (14 vs 29; P =.016). There were several other increased trends in soft tissue injury rates in the 2020 season (eg, hamstring injury [87 vs 114; P =.085]); however, these did not reach statistical significance. Conclusion: This study showed a significant increase in total injuries during the 2020 COVID-19-affected NFL regular season compared with 2019. Several major soft tissue injuries reached statistical significance in their increase from 2019 to 2020 after the cancellation of the 2020 preseason due to COVID-19. These findings suggest that organized team preseason training and conditioning could have an effect on the prevention of sport-related injury at the highest level. [ABSTRACT FROM AUTHOR]

Context: It has been reported that there is a high rate of Achilles tendon injury among kendo athletes. For protection and to support the area, kendo athletes habitually use taping during practice or games. Objective: To investigate the effect of various taping techniques on injury prevention and functional performance in kendo athletes. Design: Case-control study. Setting: Laboratory. Participants: 15 University Kendo Team athletes with at least 2 y kendo experience. Main Outcome Measures: Athletes completed 5 stepping backwards and striking cycles under 4 taping conditions: no taping, athletic taping of ankle joint (AT-Ankle), athletic taping of Achilles tendon (AT-Achilles), and Kinesio-Tex taping of Achilles tendon (KT-Achilles). Jump distance, lower limb angular motion, left foot-ground contact time, Achilles tendon force (ATF), and soleus and medial gastrocnemius muscle activities were measured. Results: Lowest peak ATF was found in AT-Achilles during heel-down phase, with statistically significant difference from KT-Achilles peak force. Significant decline of soleus muscle electromyography amplitude was also found when compared to no taping during heel-down phase and other conditions during pushing phase. Conversely, KT-Achilles showed significant decrease in foot-ground contact time compared with no taping and greater ankle range of motion than in AT-Ankle. Conclusion: To protect the Achilles tendon, AT-Achilles taping is recommended since it tends to decrease ATF. Conversely, to enhance athlete performance, we recommend KT-Achilles taping to speed up kendo striking motion. However, the Achilles tendon must withstand greatest forces concurrently. This finding implies that AT-Achilles taping can protect the injured Achilles tendon and KT-Achilles taping can enhance performance on the kendo striking motion. [ABSTRACT FROM AUTHOR]

Background. Scarless healing comprises the ultimate goal after an injury. Since tendon healing results in a fibrotic scar, an injured tendon can never regain the mechanical potential and strength of its uninjured form. A wide variety of studies focus on the tendon healing with an absent or minimal peritendinous adhesions. However, no simple method has managed it at all. Possible complex actions and peritendinous environmental events take place during the tendon healing process. Tamoxifen (TAM), besides its breast cancer-related usage, is a potent antifibrotic drug. Here, we aimed to reduce the peritendinous adhesion with TAM administration. Methods. Achilles tendons of 44 Wistar albino rats were randomly distributed in 4 groups. In group 1, bilateral lower extremities were used as control and sham. Groups 2 and 3 were comprised of low-dose (1 mg/kg) and high-dose (40 mg/kg) systemic administration of TAM, respectively. Group 4 included local administration (1 mg/kg) of TAM. Biomechanical, macroscopical, and histopathological analyses were done and compared statistically. Biomechanically, the maximum force that led to tendon rupture was determined, and tensile force data were recorded via tensile testing device. Macroscopical and histopathological analysis were composed of the quantity, quality, and grade of peritendinous adhesions. Results. Macroscopic and histopathologic findings revealed that groups 2 and 3 had a variety of values ranging between slight to severe adhesions. In group 2, almost half of the animals had moderate adhesions, whereas in group 3, the majority of the animals had moderate adhesions. There were no animals with moderate or severe adhesions in group 4. Statistically significant values were calculated between sham and control groups. Biomechanically, group 2 showed the most significant result. The tendons in group 2 had the highest stiffness when maximal force was applied to rupture the tendons. Henceforth, all these consequences were proven statistically. Conclusion. We achieved less peritendinous adhesion with the local administration of TAM when compared to systemic administration of TAM. A better understanding of the peritendinous environmental process will reveal to develop new therapies in the prevention of peritendinous adhesions. [ABSTRACT FROM AUTHOR]

Background: The optimal management for Achilles tendon (AT) ruptures is controversial and still continues to encourage debate. Conventionally, operative repair was favoured secondary to its lower rates of re-rupture, however in more recent years, we have seen promising results and a reduction in complications with conservative management. One reason for this improvement may be due to the introduction of a functional weight-bearing orthosis, however, results for complete AT ruptures is still unclear. This study aims to evaluate the functional outcomes of early weight bearing in a functional orthosis for conservatively managed, complete AT ruptures.Methodology: This study was done at East Kent Hospital University Foundation Trust in between 2019-2020. In this prospective study, we have analysed data from 41 patients with US diagnosed compete AT ruptures, with a gap less than 5 cm. Every patient was treated in a functional weight-bearing orthosis (VACOped®) for 8 weeks with early weight-bearing following a specific treatment protocol, followed by rehabilitation with a trained physiotherapist. All patients received a final follow-up at 1 year post injury, where we recorded the following functional outcome measurements on each leg: calf girth, single leg heel raise height, single leg heel raise repetitions and the ATRS score.Result: Our study population was predominantly male with an average age of 50 (range 22-79). The majority of the cohort were physically active, with more than 75% involved in a form of sporting activity pre-injury and 15% involved in higher level activity and competitive sport. The mean ATRS score was 82.1, with a re-rupture rate of only 2%. The average calf bulk difference was 1.6 cm, average heel raise height difference was 1.8 cm and a heel raise repetition difference of 6. There was a statistically significant correlation between ATRS score and calf muscle girth (p = 0.02). However, there was no significant correlation between ATRS score and heel raise height or single heel raise repetitions.Conclusion: Early weight-bearing in a functional orthosis provides excellent functional outcomes for conservatively managed, complete AT ruptures, and is associated with very low re-rupture rates. However, a multidisciplinary approach with a guided rehabilitation programme is essential for optimising functional outcome. [ABSTRACT FROM AUTHOR]

Background: The AGEs levels in tissues of diabetics and elderly tend to be higher than in normal individuals. This study aims to determine the effects of AGEs on Achilles tendon repair., Materials and Methods: Thirty-six male eight-week-old Sprague Dawley rats were selected in this study. The rats were randomly divided into two experimental groups and a control group after the transection of the Achilles tendon. During the tendon repair, the experimental groups were injected around the Achilles tendon with 350mmol/L (low dose group) and 1000mmol/L (high dose group) D-ribose 0.2 ml respectively to increase the AGEs level, while in the control group were given the same amount of PBS. The injections were given twice a week for six weeks. Collagen-I, TNF-α, and IL-6 expression in the healed Achilles tendon was assessed. Additionally, macroscopic, pathological, and biomechanical evaluations of Achilles tendon repair were conducted., Results: The repaired Achilles tendons in the high dose group showed severe swelling and distinctive adhesions. The histological score went up with the increase of the AGEs in the Achilles tendon (p<0.001). TNF- α and IL-6 in the Achilles tendon increased (p<0.001, p<0.001), and the production of collagen-I decreased with the accumulation of AGEs in the repaired Achilles tendon (p<0.001). The tensile strength of Achilles tendon in the high dose group was impaired significantly., Conclusion: In current study, the compromised tendon repair model induced by AGEs was successfully established in rat. The study demonstrated that AGEs significantly impair Achilles tendon repair., (© 2024. The Author(s).)

Objective: The results of surgical versus conservative treatment of acute Achilles tendon ruptures are still controversial. The objective of this study was to compare surgical and conservative treatment at a minimum follow-up of 1 year in terms of the complications, functional outcomes and clinical results., Hypotheses: There is no difference in the complications, clinical results and functional outcomes between the two treatment groups. There is no difference in the occurrence of complications or the clinical results due to the immobilization or rehabilitation protocols., Methods: This was a retrospective comparative, multicenter, non-randomized study of acute Achilles tendon ruptures treated between 01/01/2018 and 31/12/2019 at 21 study sites in France. All patients who received surgical or conservative treatment were included. The demographics, sports participation, nature of treatment, immobilization parameters (type, duration, position) and rehabilitation protocol were collected. Rerupture, general and specific complications, clinical results (heel-rise test, single-leg hop, calf circumference, ankle dorsiflexion) and the functional outcomes (ATRS, VISA-A, EFAS, SF-12) were collected at the final review., Results: Four hundred five patients were reviewed at a mean follow-up of 24 (±7) months. Surgical treatment was done in 372 patients (92%) and conservative treatment in 33 patients (8%), with these two sets of patients having comparable preoperative characteristics. There was a similar number of reruptures in the conservative group (3 cases, 9%) as in the surgical group (15 cases, 4%) (p=0.176). There were more general complications in the conservative group (24%) than in the surgical group (11%) (p=0.04). There was a 9% rate of surgery-related complications (infection, nerve damage, anesthesia after-effects). The ATRS (p=0.017), EFAS Total (p=0.013), EFAS daily living (p=0.008), and SF-12 physical (p=0.01) were better in the surgical group. Strict then relative immobilization provided the best balance between functional recovery (EFAS total of 33, p<0.01) and tendon lengthening (0°, p=0.01) without increasing the occurrence of rerupture (2%, p=0.18). Early weightbearing accompanied by immobilization and rehabilitation within 30 days did not lead to more reruptures than if it was started beyond 30 days (p=0.082 and p=0.07)., Conclusions: This study found no differences in the number of reruptures between surgical treatment and conservative treatment of acute Achilles tendon ruptures. Surgical treatment led to better clinical results but had a variable effect on improving the functional scores. No matter which treatment is used, in the ideal case, 3 weeks of strict immobilization in equinus should be followed by progressive reduction over the next 3 weeks. Early weightbearing and mobilization within 30 days did not increase the risk of rerupture; it actually optimized the clinical and functional outcomes., Level of Evidence: III; retrospective comparative, non-randomized., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Background: Achilles tendinopathy can be a devastating condition in ballet dancers. Initial medical evaluation is frequently conducted by generalist physicians, who may lack the perspective of dance and sports medicine focused training and often prescribe complete rest for chronic overuse injuries. In order to provide targeted information about Achilles tendinopathy and the unique needs of elite athletes, such as ballet dancers, we designed an educational intervention that covers relevant anatomy, physiology, biomechanics, clinical presentation and evaluation, and recommendations for initial treatment and sub-specialty referral. The objectives of this study were to determine baseline understanding of Achilles tendinopathy by generalist physicians and to evaluate the efficacy of an educational intervention on their knowledge., Methods: This was a prospective pre- post-test study, to measure improvement in knowledge about Achilles tendinopathy. Emergency Medicine and Primary Care physicians participated in an educational intervention with didactic and hands-on components. Data were analyzed using a two-tailed t -test., Results: Twenty generalist physicians participated. There was significant improvement in their knowledge of Achilles tendinopathy for all our educational objectives (Pre-test: 59% correct answers; post-test: 79% correct answers; P  < .0001; 95% CI: 6.32-10.78.)., Conclusions: A brief educational intervention leads to increased knowledge of Achilles tendinopathy in generalist physicians. By increasing awareness of Achilles tendinopathy through a standard educational model, we propose that our curriculum can be portable and accessible to all health care providers who encounter dancers and other athletes with Achilles tendinopathy and may serve as a model for expanded education to generalists about other conditions commonly encountered in ballet dancers., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objective: We propose an ultrasonic treatment for collagenase-induced tendinopathy in rat's Achilles tendon using pulses with a low number of cycles, high acoustic pressure and very low duty cycle., Methods: Twenty rats were used to perform the experiment. Four experimental groups of calcaneal tendons were studied: control (n = 6), sham (n = 4), collagenase-induced tendinopathy (n = 8) and ultrasound-treated collagenase-induced tendinopathy (n = 8). Surgical intervention was performed to expose the tendons prior to collagenase injection. A 1 MHz ultrasonic tansducer with a focusing lens was used. Ultrasonic treatments were used with an average total treatment time of 2.5 min, 20-cycle pulses, pressure amplitude p = 7 MPa, and 0.02% duty cycle. Histopathology of the samples was performed to evaluate nuclear density, acute inflammation, and signs of neovascularization. Collagen (types I and III), elastic fibers, and glycosaminoglycans were also analyzed., Results: No tendon involvement was found by the surgical process. Ultrasonic treatment is safe, as it does not affect healthy tendons. When collagenase infiltrated animals were treated with US, a clear predominance of type I collagen fibers and a similar collagen ratio profile to that observed in the control and sham groups was observed, with a higher density of elastic fibers compared to the control and sham groups and a significant increase in the density of glycosaminoglycans., Conclusion: The ultrasound treatment proposed reduces the effects of the artificial collagenase lesion to reach the basal level after 45 d., Competing Interests: Conflict of interest The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Although the Achilles tendon is the largest and strongest tendon in the body, healing of the Achilles tendon is the most common injury, and this process is difficult due to poor tendon circulation; moreover, the underlying mechanism has not been fully elucidated. In our study, we aimed to investigate the effects of pentoxifylline and alpha-tocopherol administered separately or in combination on rats with Achilles tendon injury. Forty-eight male Wistar rats weighing 230 ± 30 g were used in the study. The rats were randomly divided into eight groups of six animals each. Tendons were evaluated histopathologically and biomechanically. According to the statistical analysis, the vascularity density in the pentoxifylline group on day 14 was significantly greater than that in the other groups (p < 0.05). The collagen arrangement in the pentoxifylline and alpha-tocopherol groups on day 14 was found to be firmer and smoother than that in the control group (p < 0.05). The collagen arrangement in the pentoxifylline group on day 28 was greater than that in the other groups (p < 0.05). The biomechanical results were significantly greater in all groups (p < 0.05). Pentoxifylline contributed to tendon healing both through neovascularization in the early period and by improving collagen orientation in the late period, while alpha-tocopherol had a positive effect on collagen orientation in the early period. No beneficial effects were observed when pentoxifylline and alpha-tocopherol were used together. We believe that further research is needed to understand the effects of this combination therapy on tendon healing., (© 2024 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals LLC on behalf of Orthopaedic Research Society.)

Background: Plantar flexion force in recreational athletes after repair of Achilles tendon tears has rarely been reported, due to the lack of a widely available and fast measurement method. Knowledge of this parameter would allow optimisation of muscular and sports recovery. The main objective of this study was to measure the isometric force of the triceps surae at least 1 year after unilateral Achilles-tendon repair, comparatively to the unaffected side, using a portable device. The secondary objectives were to compare Achilles tendon and calf-muscle trophicity, dorsiflexion, and the single-leg heel-rise test versus the normal side and to assess functional scores at last follow-up., Hypotheses: (i) Plantar flexion force does not differ significantly between the operated and contralateral sides. (ii) Calf-muscle trophicity, dorsiflexion, and the single-leg heel-rise test do not differ significantly between the operated and contralateral sides., Patients and Methods: This single-centre retrospective study included patients aged 18 to 65 years with a history of open repair of an acute unilateral Achilles tear at least 1 year earlier. Plantar flexion force, calf-muscle trophicity, dorsiflexion, and the heel-to-floor distance were measured on both sides and compared. The ATRS, VISA-A score, and EFAS score were determined. All complications were recorded., Results: The study included 30 patients with a mean follow-up of 20.3 months (range, 12-28 months). The operated side had significantly lower values for isometric triceps surae force, calf circumference, and heel-to-floor distance compared to the contralateral side (p<0.0001). Tendon width was significantly greater on the operated side (p<0.0001). Dorsiflexion did not differ significantly between sides (p=0.106). Mean functional score values were 91.5±6 for the ATRS (maximum, 100), 85±12 for the VISA-A score (maximum, 100), and 19.5±4 for the EFAS score (maximum, 24)., Discussion: Isometric triceps-surae force measured using a portable device at least 1 year after open surgical Achilles-tendon repair was significantly decreased compared to the contralateral side. Calf circumference and heel-to-floor distance were also significantly lower. These data indicate a need for improved monitoring of triceps surae recovery to optimise rehabilitation and sports resumption., Level of Evidence: IV, retrospective comparative cohort study., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Achilles tendon ruptures are common injuries typically sustained during sport with higher incidence in men, though little is understood regarding sex-specific risk factors or outcomes following injury management. This cross-sectional clinical study and systematic review aimed to examine sex-specific Achilles tendon rupture incidence and outcomes following intervention. This study included patients who sustained a rupture between 2011-2021, were ≥18 years old, and who had a minimum follow-up of at least six months, and evaluated age, sex, sport involvement, mechanism of injury, and postoperative complications and revision. Separately, a systematic literature review in the PubMed, EMBASE, and Cochrane databases was performed. A total of 705 male and 158 female patients were included in this retrospective study. 71.1% of men and 52.5% of women sustained a sports-related rupture (p < .001), with sport involvement demonstrating a positive correlation with revision rate (coefficient = 0.09, p = .02). A total of 21 studies with 250,907 patients (87,514 male, 35,792 female) were included in the systematic review. All studies revealed an increased incidence of ATR in men. Functional outcomes were worse in women, and female sex was an independent risk factor for postoperative complications and need for revision surgery. This study demonstrated a higher incidence of sports-related ATR in men than women, likely related to their higher ball sport participation. Although the retrospective analysis did not find a significant difference in complication or revision rates, the systematic review demonstrates poorer functional outcomes, with increased likelihood for postoperative complication and revision surgery in women as compared to men., (Copyright © 2024 the American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.)

Treatment outcomes for Achilles tendon ruptures depend upon prompt diagnosis and management. A local study in 2018 highlighted inefficiencies in patient management, and a revised protocol was introduced allowing investigation and referral to be initiated by other healthcare professionals. This retrospective audit evaluates the impact of this on the timescale from presentation to treatment. It analyzes all suspected Achilles tendon ruptures within one District General Hospital from April 2021 to March 2022. Data regarding patient timelines was compared to the 2018 study. Over 12 months, 99 patients were referred to Virtual Fracture Clinic, 87.8% (n = 87) of which had a complete or partial tear on ultrasound scan (USS). In comparison to 2018, the average time from presentation to USS request reduced from 2.9 to 1.1 days (p < .01). 95% were scanned within one week of USS request and 31.3% within 48 hours (81% and 18%, previously). The average time from USS request to scan went from 6.8 to 3.2 days (p < .01). The time from presentation to treatment decision reduced from 10.9 to 6.2 days (p < .01) and the percentage of patients with a definitive treatment plan within one week increased from 34.5% to 74.2% (p < .01). Patients required 0.8 fewer appointments (p < .01) giving an estimated total saving of $10,110 ($128 per patient) during the analyzed period. The Achilles Tendon Rupture Pathway has significantly improved the proportion of patients undergoing USS within 48 hours and receiving a treatment decision within one week. This study demonstrates an efficient, cost-saving and replicable pathway for Achilles tendon ruptures., (Crown Copyright © 2024. Published by Elsevier Inc. All rights reserved.)

Abstract: Tendon injury produces intractable pain and disability in movement, but the medications for analgesia and restoring functional integrity of tendon are still limited. In this study, we report that proteinase-activated receptor 2 (PAR2) activation in dorsal root ganglion (DRG) neurons contributes to chronic pain and tendon histopathological changes produced by Achilles tendon partial transection injury (TTI). Tendon partial transection injury increases the expression of PAR2 protein in both somata of DRG neurons and their peripheral terminals within the injured Achilles tendon. Activation of PAR2 promotes the primary sensory neuron plasticity by activating downstream cAMP-PKA pathway, phosphorylation of PKC, CaMKII, and CREB. Blocking PAR2 signaling by PAR2 small-interference RNA or antagonistic peptide PIP delays the onset of TTI-induced pain, reverses the ongoing pain, as well as inhibits sensory nerve sprouting, and promotes structural remodeling of the injured tendon. Vitamin B complex (VBC), containing thiamine (B1), pyridoxine (B6), and cyanocobalamin (B12), is effective to ameliorate TTI-induced pain, inhibit ectopic nerve sprouting, and accelerate tendon repair, through suppressing PAR2 activation. These findings reveal a critical role of PAR2 signaling in the development of chronic pain and histopathological alterations of injured tendon following Achilles tendon injury. This study suggests that the pharmaceuticals targeting PAR2, such as VBC, may be an effective approach for the treatment of tendon injury-induced pain and promoting tendon repair., (Copyright © 2024 International Association for the Study of Pain.)

Recent research shows that the functional outcome after an acute Achilles tendon rupture is comparable after conservative versus operative treatment. It is therefore recommended to treat patients conservatively, but strong reasons for surgical treatment exist. In principle, no additional radiographic diagnostic exams are indicated for the diagnosis. An appropriate anamnesis, palpable gap and positive Thompson test have an excellent sensitivity. In case of doubt, an ultrasound should be performed as the first step. A shared decision process should be pursued for establishing treatment plan. However, it is recommended that patients be treated conservatively unless strong arguments for surgical intervention are present. It is important to properly inform patients, and thus manage expectations about the expected rehabilitation process. If there is an increased risk of re-rupture, such as in athletes or during physically demanding work, surgical treatment can be considered. Then a surgical technique in which expertise and experience has been gained should be used as no difference in outcome have been found after open versus minimal invasive techniques.

Background: The formation of adhesion after tendon injury represents a major obstacle to tendon repair, and currently there is no effective anti-adhesion method in clinical practice. Oxidative stress, inflammation, and fibrosis can occur in tendon injury and these factors can lead to tendon adhesion. Antioxidant carbon dots and ursolic acid (UA) both possess antioxidant and anti-inflammatory properties. In this experiment, we have for the first time created RCDs/UA@Lipo-HAMA using red fluorescent carbon dots and UA co-encapsulated liposomes composite hyaluronic acid methacryloyl hydrogel. We found that RCDs/UA@Lipo-HAMA could better attenuate adhesion formation and enhance tendon healing in tendon injury., Materials and Methods: RCDs/UA@Lipo-HAMA were prepared and characterized. In vitro experiments on cellular oxidative stress and fibrosis were performed. Reactive oxygen species (ROS), and immunofluorescent staining of collagens type I (COL I), collagens type III (COL III), and α-smooth muscle actin (α-SMA) were used to evaluate anti-oxidative and anti-fibrotic abilities. In vivo models of Achilles tendon injury repair (ATI) and flexor digitorum profundus tendon injury repair (FDPI) were established. The major organs and blood biochemical indicators of rats were tested to determine the toxicity of RCDs/UA@Lipo-HAMA. Biomechanical testing, motor function analysis, immunofluorescence, and immunohistochemical staining were performed to assess the tendon adhesion and repair after tendon injury., Results: In vitro, the RCDs/UA@Lipo group scavenged excessive ROS, stabilized the mitochondrial membrane potential (ΔΨm), and reduced the expression of COL I, COL III, and α-SMA. In vivo, assessment results showed that the RCDs/UA@Lipo-HAMA group improved collagen arrangement and biomechanical properties, reduced tendon adhesion, and promoted motor function after tendon injury. Additionally, the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) in the RCDs/UA@Lipo-HAMA group increased; the levels of cluster of differentiation 68 (CD68), inducible Nitric Oxide Synthase (iNOS), COL III, α-SMA, Vimentin, and matrix metallopeptidase 2 (MMP2) decreased., Conclusion: In this study, the RCDs/UA@Lipo-HAMA alleviated tendon adhesion formation and enhanced tendon healing by attenuating oxidative stress, inflammation, and fibrosis. This study provided a novel therapeutic approach for the clinical treatment of tendon injury., Competing Interests: The authors report no conflicts of interest in this work., (© 2024 Peng et al.)

Tendons are one of the major load-bearing tissues in the body; subjected to enormous peak stresses, and thus vulnerable to injury. Cellular responses to tendon injury are complex, involving inflammatory and repair components, with the latter employing both resident and recruited exogenous cell populations. Gene expression analyses are valuable tools for investigating tendon injury, allowing assessment of repair processes and pathological responses such as fibrosis, and permitting evaluation of therapeutic pharmacological interventions. Quantitative polymerase chain reaction (qPCR) is a commonly used approach for such studies, but data obtained by this method must be normalised to reference genes: genes known to be stably expressed between the experimental conditions investigated. Establishing suitable tendon injury reference genes is thus essential. Accordingly we investigated mRNA expression stability in a rat model of tendon injury, comparing both injured and uninjured tendons, and the effects of rapamycin treatment, at 1 and 3 weeks post injury. We used 11 candidate genes (18S, ACTB, AP3D1, B2M, CSNK2A2, GAPDH, HPRT1, PAK1IP1, RPL13a, SDHA, UBC) and assessed stability via four complementary algorithms (Bestkeeper, deltaCt, geNorm, Normfinder). Our results suggests that ACTB, CSNK2A2, HPRT1 and PAK1IP1 are all stably expressed in tendon, regardless of injury or drug treatment: any three of these would serve as universally suitable reference gene panel for normalizing qPCR expression data in the rat tendon injury model. We also reveal 18S, UBC, GAPDH, and SDHA as consistently poor scoring candidates (with the latter two exhibiting rapamycin- and injury-associated changes, respectively): these genes should be avoided., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Marr et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: The Achilles tendon is the body's strongest and largest tendon. It is commonly injured, particularly among athletes, accounting for a significant portion of serious tendon injuries. Several factors play a precipitating role in increasing the risk of these injuries., Objective: Our objective is to derive and validate a risk calculator for the prediction of incidence of any complication following Achilles tendon repair., Methods: We used de-identified data from the American College of Surgeons' National Surgical Quality Improvement Project (NSQIP) database from 2005 to 2021. It comprises 7010 individuals who had undergone Achilles tendon rupture repair. Demographic and risk factors information was collected. To develop the calculator, the sample was divided into a derivation cohort (40%) and a validation cohort (60%). Multivariate logistic regression was used for statistical analysis, and a risk calculator for incidence of any complication was derived from the derivation cohort and validated on the remaining 60% of the sample. Patients with missing data were excluded, and the significance level was set at p < 0.05., Results: We analyzed the derivation cohort of 2245 individuals who underwent Achilles tendon repair surgery between 2005 and 2021, with a 5.5% overall complication. Multivariate logistic regression identified anesthesia type, ASA classification, certain co-morbidities (pre-operative dialysis and medication-requiring hypertension), and wound classification as significant predictors of complications. The developed risk calculator model had an area under the curve (AUC) of 0.685 in the derivation cohort and 0.655 in the validation cohort, surpassing the widely used and validated modified frailty index. A cut-off score threshold of 0.06 was established using Youden's index to dichotomize individuals into low and high risk for developing any postoperative complications., Conclusion: Our risk calculator includes factors that most significantly affect the incidence of any complication following Achilles tendon repair., (© 2024. The Author(s).)

Background: In recent decades, early rehabilitation after Achilles tendon rupture (ATR) repair has been proposed. The aim of this prospective cohort study was to compare different immobilisation durations in order to determine the optimal duration after open surgery for ATR repair., Methods: This study included 1088 patients (mean age, 34.9 ± 5.9 years) who underwent open surgery for acute ATR repair. The patients were categorised into four groups (A, B, C, and D) according to postoperative immobilisation durations of 0, 2, 4, and 6 weeks, respectively. All patients received the same suture technique and a similar rehabilitation protocol after brace removal,; they were clinically examined at 2, 4, 6, 8, 10, 12, 14, and 16 weeks postoperatively, with a final follow-up at a mean of 19.0 months. The primary outcome was the recovery time for the one-leg heel-rise height (OHRH). Secondary outcomes included the time required to return to light exercise (LE) and the recovery times for the range of motion (ROM). Data regarding the surgical duration, complications, the visual analogue scale (VAS) score for pain, the Achilles tendon Total Rupture Score (ATRS), and the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale score were also collected., Results: The recovery times for OHRH, LE, and ROM were significantly shorter in groups A and B than in groups C and D (P < 0.001). The VAS scores decreased over time, reaching 0 in all groups by 10 weeks. The mean scores in groups A and B were higher than those in the other groups at 2 and 4 weeks (P < 0.001), whereas the opposite was true at 8 weeks (P < 0.001). ATRS and the AOFAS Ankle-Hindfoot scale score increased across all groups over time, showing significant between-group differences from weeks 6 to 16 (P < 0.001) and weeks 6 to 12 (P < 0.001). The mean scores were better in groups A and B than in groups C and D. Thirty-eight complications (3.5%) were observed, including 20 re-ruptures and 18 superficial infections. All complications were resolved at the last follow-up, with no significant between-group differences., Conclusions: Immobilisation for 2 weeks after open surgery for ATR repair may be the optimal strategy for early rehabilitation with relatively minimal pain and other complications., Trial Registration: ClinicalTrials.gov (NCT04663542)., (© 2024. The Author(s).)

Objectives: This study aimed to evaluate the biomechanical and histological effects of fluoroquinolones on surgically repaired tendon healing., Materials and Methods: The Achilles tendons of 40 Wistar rats (mean weight: 213.5 g; range 201 to 242 g) were bilaterally surgically cut and repaired. The rats were randomly divided into four groups: the first and third groups were designated as control groups and did not receive drug therapy, whereas the second and fourth groups received 300 mg/kg ciprofloxacin for a week after the surgical procedure. The first and second groups had both tendons dissected at the end of the first week, while the third and fourth groups were dissected at the end of the third week. The left tendons were examined biomechanically, while the right tendons were examined histologically., Results: Statistical analysis revealed that the mean maximum tensile forces of tendons in the first and second groups were 5.2±1.84 N (range, 2.9 to 8.5 N) and 11.1±2.65 N (range, 7.3 to 13.9 N), respectively, which was found to be statistically significant (p< 0.05). At the end of the third week, mean maximum tensile forces of the third and fourth groups were determined to be 20.7±5.0 N (range, 22.1 to 29.8 N) and 28.7±4.6 N (range, 22.1 to 36.8 N), respectively, which was also statistically significant (p< 0.05). Histologically, our results were compatible., Conclusion: This study demonstrated that ciprofloxacin did not exhibit the expected adverse effects on surgically repaired tendon healing in the early stages but likely contributed to healing in the short term by affecting the inflammatory phase.

Tendons, complex fibrous structures, are subjected to great tensions, which can give rise to the so-called tendinopathies. This study aimed to evaluate photobiomodulation and human Amniotic Membrane applied as single or combined therapies to treat induced Achilles tendon lesions. Seventy-five rats were divided into five groups (n=15): C- control Sham surgery; I- tendon injury; LA- tendon injury treated with photobiomodulation; AM- tendon injury treated with Amniotic Membrane; LAM- tendon injury + photobiomodulation and Amniotic Membrane, subdivided into three groups (n=5) with analysis at 3, 7, and 14 days. The tendon injuries were made with a 20 g weight released from a mini guillotine onto the ankle in dorsiflexion. AM and LAM groups received an Amniotic Membrane fragment while LA and LAM groups received transcutaneous photobiomodulation, using a 660 nm wavelength laser. The inflammatory cells showed statistical differences between groups C and I (p<0.05), I and AM (p<0.01), I and LA (p<0.05), and I and LAM (p<0.01). Both photobiomodulation and Amniotic Membrane were shown to enhance tendon repair, and the association of photobiomodulation plus Amniotic Membrane was the most effective treatment. We conclude that the association of photobiomodulation plus Amniotic Membrane was effective in accelerating and improving the tendon regeneration process.

Achilles tendon reconstruction is an effective method of repairing Achilles tendon rupture defects. We introduce a new approach for Achilles tendon reconstruction using transversal calcaneal anchored autogenous semitendinosus tendon graft. The study aimed to evaluate the clinical role of this new Achilles tendon reconstruction. We retrospectively enrolled patients who underwent Achilles tendon reconstruction using transversal calcaneal anchored autogenous semitendinosus tendon graft for acute Achilles tendon rupture defects from 2016 to 2021. The clinical and radiological results were assessed at the preoperative and the final postoperative follow-up with Visual Analog Score (VAS) scores, American Orthopaedic Foot & Ankle Society (AOFAS) scores and Achilles tendon Total Rupture Scores (ATRS). Besides, at the last postoperative follow-up, the difference in ankle range of motion between the two side of the patients and the incidence of postoperative complications were recorded. Results revealed patients had significantly lower VAS and higher AOFAS and ATRS (P < 0.01). Compared to the healthy ankle, the operative ankle showed significant deficits in ankle range of motion (P < 0.01). Additionally, radiological results showed no noticeable signs of tunnel enlargement in the calcaneus and no patient had re-rupture. Transversal calcaneal anchored Achilles tendon reconstruction with free semitendinosus tendon autograft is an effective treatment option for patients with acute Achilles tendon rupture with large defects and have high postoperative exercise demands., (© 2024. The Author(s).)

Purpose: Achilles tendon ruptures (ATRs) close to the insertion, in high-level athletes, and in patients at high risk of re-rupture, may be better suited to operative repair. Minimally Invasive Repair (MIR) of the Achilles tendon has excellent outcome and low complication rates. Traditionally MIR has showed lower repair strength, failing due to suture pull-out from the distal tendon stump. The aim of this study was to describe the outcome of ATR patients who received transosseous distal suture placement using a standard technique as a reference., Methods: Following ATR, patients were evaluated for pre-injury activity level, body weight, location of the tear and size of the distal Achilles tendon stump. Patients considered to be at high-risk of re-rupture: Tegner level ≥ 8, body weight ≥ 105Kg and distal ATR, received transosseous (TO) distal suture placement (n = 20) rather than the usual transtendinous (TT) technique (n = 55). Patient reported outcome measures and functional evaluation was performed at 12 months following repair., Results: At 12 months follow up both methods resulted in good median (IQR) Achilles tendon Total Rupture Score TO 83.8 (74-88.3) vs. TT 90 (79-94), low increased relative Achilles Tendon Resting Angle TO -3.5˚ (3.6) vs. TT -3.5˚ (3.3) and mean (SD) Single leg Heel-Rise Height Index TO 88.2% (9.9) vs. TT 85.6% (9.9) (n.s.). There were 4 re-ruptures in the high-risk group and 2 in the group receiving TT distal suture placement. All but one of these were traumatic in nature. The mode of failure following TO distal suture placement was proximal suture pull out., Conclusions: To distal suture placement during minimally-invasive Achilles tendon repair for higher-risk patients can lead to results equivalent to those in lower-risk patients treated with a standard TT MIR technique, except for the re-rupture rate which remained higher. There may be factors that have greater influence on outcome other than suture placement following ATR., (© 2024. The Author(s).)

With up to 50 incidents per 100,000 inhabitants, Achilles tendon ruptures are among the most frequent tendon injuries encountered in orthopedics and trauma surgery. Apart from high-risk forms of sport, degenerative processes are primarily responsible for weakening and ultimately rupture. In addition to assessing the typical clinical signs with inability to perform powerful plantar flexion, the diagnostics include easy to earn examination techniques, such as the Thompson test and ultrasound as the imaging gold standard. Conservative and surgical treatment are available depending on the constitution, age and requirements of the patient. The latter option is divided into conventional open, minimally invasive or percutaneous procedures. Good to very good results can be expected regardless of the form of treatment, provided that early functional rehabilitation is carried out. The average rerupture rate is 5% and the return to sport rate is around 80%., (© 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Substantial research on complete Achilles tendon ruptures is available, but guidance on partial ruptures is comparatively sparse. Conservative management is considered acceptable in partial tendon ruptures affecting less than 50% of the tendon's width, but supporting experimental evidence is currently lacking. Using a previously validated finite element model of the Achilles tendon, this study aimed to assess whether loading conditions simulating an early functional rehabilitation protocol could elicit progression to a complete rupture in partial ruptures of varying severity. In silico tendon rupture simulations were performed to locate the most likely rupture site for least, moderate, and extreme subtendon twist configurations. These three models were split at the corresponding rupture site and two sets of partial ruptures were created for each, starting from the medial and lateral sides, and ranging from 10% to 50% loss of continuity. Simulations were conducted with material parameters from healthy and tendinopathic tendons. Partial ruptures were considered to progress if the volume of elements showing a maximum principal strain above 10% exceeded 3 mm 3 . To assess whether the tendinopathic tendons typical geometric characteristics could compensate for the inferior material properties found in tendinopathy, an additional model with increased cross-sectional area in the free tendon region was developed. Progression to complete ruptures occurred even with less than a 50% loss of continuity, regardless of subtendon twisting, and material parameters. The tendinopathic tendon model with increased cross-sectional area showed similar results. These findings suggest the current criteria for surgical treatment of partial ruptures should be reconsidered. Statement of clinical significance: The clinical significance and most appropriate treatment of partial ruptures of the Achilles tendon is unclear. Despite the widespread use of the "50% rule" in treatment decisions of partial tendon ruptures, experimental evidence supporting it is missing. The present study provides new data, from a validated aponeurotic and free Achilles tendon finite element model, showing that partial ruptures may progress to complete ruptures under loading conditions elicited from functional rehabilitation protocols, even for partial ruptures affecting less than 50% of the tendon's width. Under these novel findings, the current criteria for surgical treatment of partial ruptures should be reconsidered., (© 2024 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals LLC on behalf of Orthopaedic Research Society.)

Background: The influence of social determinants of health (SDH) on postoperative complications has been investigated in several studies, although correlation with Achilles tendon rupture (ATR) repair remains uninvestigated. SDH encompasses several factors, including insurance status and area-based measurements, including the Area Deprivation Index (ADI) and Social Vulnerability Index (SVI), which ranks neighborhoods by social disadvantage. This study investigated the correlation between patient demographics, SDH, and complications following ATR repair., Methods: A retrospective cohort study was conducted on 521 patients who presented with acute ATR and met the inclusion criteria, including age ≥18 years, a minimum of 30-day follow-up, and repair within 28 days of rupture. We reviewed patient demographics, time to surgery (TTS), and postoperative complications, including venous thromboembolism (VTE), rerupture, surgical site infection (SSI), wound dehiscence, and sural nerve injury. SDH variables included race, smoking status, insurance status, level of education, ADI, and SVI. Univariate regression tested the correlation between complications and SDH indicators. Significant variables ( P  < .05) were included in a multivariate regression., Results: Sixty-eight complications occurred in 59 patients (11.3%). Multivariate regression showed that a higher ADI, that is, socially deprived individuals, was associated with lower rates of VTE (OR = 0.41, P  = .04). Higher body mass index (BMI) was associated with rerupture (OR = 8.73, P  < .01). Male patients had lower rates of wound dehiscence (OR = 0.31, P  = .03) and VTE (OR = 0.32, P  = .02) compared with women. Longer TTS correlated with sural nerve injuries (OR = 2.23, P  < .01) and shorter TTS with reruptures (OR = 0.02, P   =  .02)., Conclusion: Some measures of SDH were associated with postoperative complications. Gender also may have an effect, with male sex associated with lower rates of wound dehiscence and VTE. BMI was associated with higher rates of reruptures and overall general complications., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Disclosure forms for all authors are available online.