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Increasing antibiotic resistance has been reported as an issue in the treatment of periprosthetic joint infection (PJI). A repeat two-stage revision for recurrent PJI is at high risk of reinfection. However, it is unclear if the microorganism profile plays a role with potentially more resistant or polymicrobial infections. This is a retrospective, single-center analysis of two-stage revisions performed between 2011 and 2017. We identified 46 patients who underwent a repeat resection arthroplasty for recurrent PJI of the same joint after a previous two-stage revision of the same joint at the same department. All microbiological findings were analyzed focusing on microbiological spectrum and resistance testing as well as the potential impact on reinfection-free survival. The most common organism found at the time of recurrent PJI were coagulase-negative Staphylococci (39%) followed by Gram-negative organisms (28%). The risk of polymicrobial infections, difficult-to-treat resistant organisms, and Gram-negative infections increased significantly. Among staphylococcal infections, there was a high percentage of methicillin-resistant species and resistance to oral antibiotics. Patients with Gram-negative organisms had a reduced infection-free survivorship, while resistant organisms were not associated with decreased survival. Patients who undergo a repeat two-stage revision for recurrent PJI have more polymicrobial and resistant organisms, although the impact on survivorship is unclear. [ABSTRACT FROM AUTHOR]

Periprosthetic joint infection is a feared complication after the megaprosthetic reconstruction of oncologic and non-oncologic bone defects of including the knee or hip joint. Due to the relative rarity of these procedures, however, optimal management is debatable. Considering the expanding use of megaprostheses in revision arthroplasty and the high revision burden in orthopedic oncology, the risk of PJI is likely to increase over the coming years. In this non-systematic review article, we present and discuss current management options and the associated results focusing on studies from the last 15 years and studies from dedicated centers or study groups. The indication, surgical details and results in controlling infection are presented for debridement, antibiotics, irrigation and retention (DAIR) procedure with an exchange of the modular components, single-stage implant exchange, two-stage exchanges and ablative procedures. [ABSTRACT FROM AUTHOR]

Poly-L-lactic acid (PLLA) implants have been used for bone fixation for decades. However, upon insertion, they can cause a foreign body reaction (FBR) that may lead to complications. On 15 December 2023, a systematic review was conducted to search for articles on the PubMed, MeSH term, and Scopus databases using the keywords 'PLLA' and 'foreign body reaction'. The articles were reviewed not only for the question of FBR, its severity, and the manifestation of symptoms but also for the type of implant and its location in the body, the species, and the number of individuals included. A total of 71 original articles were identified. Of these, two-thirds reported on in vivo trials, and one-third reported on clinical applications. The overall majority of the reactions were mild in more than half of the investigations. Symptoms of extreme and extensive FBR mainly include osteolysis, ganglion cysts, and swelling. The localization of PLLA implants in bone can often result in osteolysis due to local acidosis. This issue can be mitigated by adding hydroxyapatite. There should be no strong FBR when PLLA is fragmented to 0.5–4 µm by extracorporeal shock wave. [ABSTRACT FROM AUTHOR]

Bacterial biofilms on foreign surfaces are considered a primary cause of implant-related infections, which are challenging to treat. A new implant coating was developed, containing anti-infective silver within a biocompatible polymer carrier substance. In addition to its passive effect on the implant surface, highly concentrated anti-infective silver can be released as needed via the application of high-energy shock waves. This intervention could be applied transcutaneously in a clinical setting without the need for additional surgery. We investigated the inhibition of biofilm formation and the effectiveness of eradication after activation of the coating via shock waves in an in vitro biofilm model using Staphylococcus epidermidis RP62A. This was performed via scanning electron microscopy and quantitative microbiology. Additionally, we examined the cytotoxicity of the new coating on normal human fibroblasts and Saos-2 osteoblast-like cells, depending on the silver concentration. All studies were compared to uncoated titanium surfaces Ti6Al4V and a conventional electroplated silver coating. Cytotoxicity toward normal human fibroblasts and Saos-2 osteoblast-like cells increased with higher silver content but remained tolerable at 6%. Compared to uncoated Ti6Al4V and the electroplated silver coating, the new coating with a silver content of 4% and 6% exhibited a significant reduction in adherent bacteria by a factor of approximately 1000. This was also evident via microscopic examination of the surface morphology of the biofilms. Furthermore, following shock wave activation, no bacteria were detectable on either the implant or in the surrounding fluid after a 24 h period. [ABSTRACT FROM AUTHOR]

Simple Summary: Reconstructing the proximal humerus after tumor resection remains a significant challenge, often resulting in reduced function and a diminished quality of life for patients due to the loss of soft tissues and bone. This research highlights the advantages of using an inverse tumor prosthesis for patients with proximal humerus bone tumors. It offers long-term results that have not been available in the existing literature, addressing concerns related to potential complications such as prosthetic loosening, infection, dislocation, and the loss of function. This study is valuable as it provides insight into an effective reconstruction method for a complex problem, fostering further research refinement in this field. Reconstructing the proximal humerus after tumor removal is challenging due to muscle and bone loss. The current methods often result in poor shoulder function. This study assessed the long-term functional and oncological outcomes of using an inverse proximal humerus prosthesis in 46 patients with bone tumors. The results showed a mean range of motion of 62° in anteversion, 28° in retroversion, and 55° in abduction. Notably, 23 patients achieved over 90° of shoulder abduction, with an average of 140°. The median Musculoskeletal Tumor Society Score was 25. Complications included infection in two radiotherapy patients and single dislocations in seven patients. One patient with recurrent dislocations needed revision surgery. In conclusion, the use of the inverse proximal humerus prosthesis in bone tumor treatment yields excellent shoulder function and high patient satisfaction. This approach is especially beneficial for those with metastatic disease. [ABSTRACT FROM AUTHOR]

Background: Rotating-hinge knee (RHK) implants are an option for knee arthroplasty in cases of instability or severe bone loss. However, the revision rate can be increased compared to unconstrained implants which mandate improvements in implant design. This study investigates a novel RHK design for total knee arthroplasty (TKA). Methods: Retrospective analysis of a single design RHK TKA (GenuX MK, Implantcast) implanted between 2015 and 2019 including 133 patients (21 primary TKA, 112 revisions). The main indication for revision TKA was second-stage reimplantation following infection. The median follow-up amounted to 30 months (IQR 22–47). Results: In total, 13% (18/133) of patients underwent revision surgery after a mean time of 1 month (IQR 0–6). The main reason for the revision was (re-) infection in 8% of patients. All revisions were performed following revision TKA and none following primary TKA. There were no revision surgeries for loosening or instability. The revision-free implant survival of 83% was (95% CI 75–91%) after five years. A higher number of previous surgeries was associated with a greater revision risk (p = 0.05). Conclusion: Revision and complex primary TKA using a single-design RHK implant results in good implant survival at mid-term follow-up although infection remains a major concern. [ABSTRACT FROM AUTHOR]

Implant-related infections are a significant concern in orthopedic surgery. A novel anti-infective implant coating made of bioresorbable polymer with silver nitrate was developed. A controlled release of silver ions into the vicinity of the prosthesis can be triggered on-demand by extracorporeal shock waves to effectively combat all clinically relevant microorganisms. Microscopy techniques were used to examine the effects of shock wave application on coated titanium discs. Cytotoxicity was measured using a fibroblast proliferation assay. The anti-infective effect was assessed by monitoring the growth curves of three bacterial strains and by conventional culture. Microscopic analysis confirmed surface disruption of the coatings, with a complete release of silver in the focus area after shock wave application. Spectrometry detected an increase in silver concentration in the surrounding of the discs that surpassed the minimum inhibitory concentration (MIC) for both S. epidermidis RP62A and E. coli ATCC 25922. The released silver demonstrated an anti-infective effect, significantly inhibiting bacterial growth, especially at 6% and 8% silver concentrations. Cytotoxicity testing showed decreasing fibroblast viability with increasing silver concentration in the coating, with 6% silver maintaining viability above 25%. Compared to a commonly used electroplated silver coating on the market, the new coating demonstrated superior antimicrobial efficacy and lower cytotoxicity. [ABSTRACT FROM AUTHOR]

Background: Increasing antibiotic resistance has been reported as an issue in the systemic treatment of periprosthetic joint infection (PJI). Linezolid offers the advantages of high oral bioavailability and little resistance; however, efficacy in the treatment of PJI varies considerably, and studies reporting consistent surgical treatment are scarce. Methods: This is a retrospective, single-center analysis of two-stage revisions performed between 2008 and 2017. We identified 111 patients who met the inclusion criteria. Oral linezolid was given for 28 days following 14 days of intravenous tailored antibiotics in resistant gram-positive PJI. A total of 64% of the patients had methicillin-resistant coagulase-negative staphylococci. The median follow-up was 43 (interquartile range (IQR) 30–57) months. Results: 22% (24/111) of the patients underwent surgery for subsequent infection. The 5-year infection-free survival probability was 77% (95% confidence interval (CI) 69–85). A total of 5% of the patients (6/111) had the same organism at the time of reinfection. The patients with infections caused by other organisms than Coagulase-negative staphylococci tended to have a worse reinfection-free survivorship at five years (70% vs. 81%, p = 0.09). Furthermore, the patients with obesity tended to have reduced reinfection-free survivorship at five years (69% vs. 84%, p = 0.08). Overall, 5% (6/111) of the patients had blood count abnormalities with no treatment discontinuations. Conclusion: Two-stage revision arthroplasty with systemic oral linezolid treatment for resistant gram-positive PJI results in an infection control of 77% at the mid-term. [ABSTRACT FROM AUTHOR]

Simple Summary: Primary bone sarcomas around the distal humerus are rare. Following tumor resection, distal humeral replacement (DHR) is a limb-salvage option for the reconstruction of the resulting bone defect. Due to small patient numbers, the postoperative functional outcome and resumption of sporting activities among affected patients remain mostly unclear although they become increasingly important with improvements in patients' life expectancy and quality of life. Thus, the aims of our study were to evaluate the functional outcome, assess the return to sport activities, and identify the potential limiting and beneficial factors in a large homogenous patient cohort treated with a single-design modular implant at a tertiary sarcoma center. Distal humeral replacement (DHR) is a limb-salvage option for the endoprosthetic reconstruction of bone defects following the resection of a primary bone sarcoma. As primary bone sarcomas are only occasionally located around the distal humerus, there is a paucity of information regarding postoperative function, and patients' resumption of sporting activities. With advances in diagnostics and in surgical and oncological treatment leading to an increased patient life expectancy and higher quality of life, patients' functional outcome and return to sports activities are of increasing interest. Between 1997 and 2021, a total of 24 patients underwent DHR with a single-design modular implant at a tertiary sarcoma center. A total of 14 patients who died of their disease were excluded, leaving a study cohort of 10 patients, with a median age of 30 years on the day of surgery (IQR 20–37). At the last follow-up, after a median of 230 months (IQR 165–262), the median MSTS was 19 (IQR 13–24), the median TESS was 79 (IQR 66–87), the median SEV was 38% (IQR 24–53), the median TS was 6 (IQR 4–7), and the median WAS was 3 (IQR 1–8). Among the variables of gender, surgery on the dominant extremity, intraoperative nerve resection, extra-articular tumor resection, chemotherapy, radiotherapy, and revision surgeries, none were associated with a better/lower functional outcome score or return to sports activities. However, a higher level of sports performance prior to diagnosis (WAS > 10) was associated with a higher level of sports performance postoperatively (p = 0.044). [ABSTRACT FROM AUTHOR]

(1) Background: Prior to revision hip (THA) or knee arthroplasty (TKA), periprosthetic low-grade infection (PJI) should be ruled out. Despite advances in preoperative diagnosis, unsuspected positive cultures (UPCs) may occur in initially planned aseptic revisions. Particularly, single UPCs pose a diagnostic and therapeutic dilemma, as their impact on outcome is unclear and recommendations are heterogeneous. This review investigates the frequency of single UPCs and their impact on implant survivorship. (2) Methods: In July 2022, a comprehensive literature search was performed using PubMed and Cochrane Library search. In total, 197 articles were screened. Seven retrospective studies with a total of 5821 cases were able to be included in this review. (3) Results: Based on the cases included, UPCs were found in 794/5821 cases (14%). In 530/794 cases (67%), the majority of the UPCs were single positive. The most commonly isolated pathogens were coagulase negative Staphylococci and Cutibacterium acnes. Five of seven studies reported no influence on revision- or infection-free survival following a single positive culture. In two studies, single UPCs following THA revision were correlated with subsequent re-revision for PJI. (4) Conclusions: Single UPCs of a non-virulent pathogen following presumed aseptic TKA revision may be interpreted as contaminants. A single UPC following THA revision may be a risk factor for subsequent PJI. The role of systemic antibiotic treatment remains unclear, but it should be considered if other risk factors for PJI are present. [ABSTRACT FROM AUTHOR]

Leg length discrepancies (LLD) are frequently associated with coronal malalignment. Temporary hemiepiphysiodesis (HED) is a well-established procedure for the correction of limb malalignment in skeletally immature patients. For treatment of LLD > 2 cm, lengthening with intramedullary devices gains increasing popularity. However, no studies have investigated the combined application of HED and intramedullary lengthening in skeletally immature patients. This retrospective single-center study evaluated the clinical and radiological outcomes of femoral lengthening with an antegrade intramedullary lengthening nail combined with temporary HED performed in 25 patients (14 females) between 2014 and 2019. Temporary HED through the implantation of flexible staples of the distal femur and/or proximal tibia was either performed prior (n = 11), simultaneously (n = 10) or subsequently (n = 4) to femoral lengthening. The mean follow-up period was 3.7 years (±1.4). The median initial LLD was 39.0 mm (35.0–45.0). Twenty-one patients (84%) presented valgus and four (16%) showed varus malalignment. Leg length equalization was achieved in 13 of the skeletally mature patients (62%). The median LLD of the eight patients with residual LLD > 10 mm at skeletal maturity was 15.5 mm (12.8–21.8). Limb realignment was observed in nine of seventeen skeletally mature patients (53%) in the valgus group, and in one of four patients (25%) in the varus group. Combining antegrade femoral lengthening and temporary HED is a viable option to correct LLD and coronal limb malalignment in skeletally immature patients; however, achieving limb length equalization and realignment may be difficult in cases of severe LLD and angular deformity, in particular. [ABSTRACT FROM AUTHOR]

Proximal junctional kyphosis (PJK), as one of the most discussed problems after corrective surgery in adolescent idiopathic scoliosis (AIS), is still not fully clarified and seems to be multifactorial. Biomechanical and a few clinical studies have shown the influence of destruction of posterior ligaments by resection of spinous processes and some parameters concerning rod contouring as risk factors for PJK. To verify these results, 192 patients with AIS and corrective surgery via a posterior approach between 2009 and 2017 were included. Radiographic parameters were analyzed preoperatively (preOP), postoperatively (postOP), and with a mean follow up (FU) of 27 months. The participants were divided into two groups (PJK group and non-PJK group). The incidence of PJK was 15.6%. Contrary to the results of biomechanical studies, we could not find any significant influence of the spinous process resection. However, the PJK group had significantly larger preOP T4–T12 kyphosis (31.1° ± 13.93° vs. 23.3° ± 14.93°, p = 0.016). Furthermore, the PJK group showed a significantly larger rod contour angle (RCA) (8.0° ± 4.44° vs. 5.9° ± 3.28°, p = 0.003) and mismatch of postOP proximal junctional angle (PJA) and RCA (3.5° ± 5.72° vs. 0.9° ± 4.86°, p = 0.010) compared to the non-PJK group. An increase in the mismatch of postOP PJA and RCA (OR = 1.14, p = 0.008) and a high RCA are risk factors for PJK and need to be focused on by surgeons. [ABSTRACT FROM AUTHOR]

(1) Purpose: Lower limb deformities can have a severe impact on health-related quality of life (HRQL). LIMB-Q Kids is a new patient-reported outcome measure (PROM) aiming to elucidate the experience of 8–18-year-old patients before, during and after treatment, and to measure the different aspects of HRQL. The aim of this study was to translate and culturally adapt LIMB-Q Kids to German. (2) Methods: The International Society for Pharmacoeconomics and Outcomes Research (ISPOR) guidelines were followed. Three forward translations, a backward translation, an expert panel meeting with eight participants, and twenty cognitive debriefing interviews led to the final German version of LIMB-Q Kids. (3) Results: In the forward translations, 4/159 items were difficult to translate, and 2/159 items in the backward translation differed from the original English version. Cognitive debriefing interviews with 20 patients identified 7/159 items that were difficult to comprehend/answer, and 2 of these items were changed. (4) Conclusions: Lower limb deformities can have a great impact on children, and it is important to measure and consider the impact on HRQL. In order to be able to use PROMs in different countries, conceptually equivalent translations and cultural adaptations should be performed in order to ensure comprehensibility. The final German version of LIMB-Q Kids is ready for use in an international field test. [ABSTRACT FROM AUTHOR]

Background: Patient-reported outcome measures are gaining increasing importance in clinical research and quality control. Clinical impairment through limb deformities can appear in various forms. This study aimed at translating and culturally adaptating the Limb Deformity-Scoliosis Research Society (LD-SRS) patient-reported outcome measure (PROM) into German by following the scientific rigor of the cross-cultural adaptation process as well as ensuring the reliability of the translated version. The LD-SRS is applicable in children and adults. Methods: The translation was performed in accordance with the creators of the LD-SRS following the Professional Society for Health Economics and Outcomes Research (ISPOR) guidelines for translation and cultural adaptation. Two forward translations were performed, and after a consensus meeting, a professional translator translated the PROM back to English. The creators reviewed the back translation of the preliminary German version. Thirty patients with upper and lower limb deformities participated in cognitive debriefing interviews. The version was proofread and, finally, the test-retest reliability was estimated. Results: The mean age was 19 years (range 6–61). Twenty-six patients (87%) completed the retest after 6 days (range 3–26). The internal consistency was estimated with a Cronbach's alpha of 0.96 (range 0.94–0.97), and the intraclass correlation was 0.92 (range 0.89–0.94), indicating an excellent reliability. The scores were normally distributed. Thereafter, the German version was proofread and finalized. Conclusions: The German translation and cross-cultural adaptation of the LD-SRS score resulted in a high reliability and internal consistency. The German LD-SRS score is readily usable and may be applied in future studies of German-speaking limb deformity patients. [ABSTRACT FROM AUTHOR]

Simple Summary: Postoperative infection is one of the gravest complications in patients following megaprosthetic replacement due to primary malignant bone tumors. On the other hand, several studies have also suggested that patients with a variety of different cancers may have a better chance of survival following the development of an infection, possibly as a result of the immune and inflammatory host responses to infection. Our retrospective analysis of 437 extremity osteosarcoma patients found that patients with a poor response to neoadjuvant chemotherapy and an infection in the first 12 months after primary tumor surgery had a better chance of survival compared to patients without infections. If this finding can be validated in a different patient cohort, it would suggest that the efficacy of novel immunomodulatory treatments in osteosarcoma patients should be evaluated and reported separately for patients with a good and a poor response to preoperative chemotherapy, as the latter might benefit more from such treatments. Recent retrospective studies suggested that early postoperative infections might be associated with a survival benefit for extremity osteosarcoma patients, but the reported results have been conflicting. The files of 437 patients with a newly diagnosed, high-grade osteosarcoma of the extremities treated at 5 referral centers in Germany and Austria between 1989 and 2016 were retrospectively evaluated. All patients underwent multi-agent chemotherapy and limb-sparing tumor excision, followed by endoprothetic replacement. We used the Kaplan–Meier method to calculate survival curves, which we compared with the log-rank test. With a median follow-up of 100 months (interquartile range, 49–155 months), local recurrence (LR) probability, event-free survival (EFS), and disease-specific survival (DSS) after 5 years in this selected patient cohort amounted to 5%, 67%, and 79%, respectively, and 46 patients (10.5%) developed an early postoperative infection. We found no significant differences in LR, EFS, or DSS between patients with and without early infections, and there were no differences in known prognostic factors between the two groups. However, in subgroup analyses patients with a poor response to neoadjuvant chemotherapy and an early infection had a better DSS compared to patients without early infections (93% vs. 62% after 5 years, p = 0.044). Provided that our findings can be validated in separate patient cohorts, we believe that patient outcome after adjuvant immunomodulatory treatments in osteosarcoma patients should be evaluated and reported separately for good and poor responders to neoadjuvant chemotherapy in future studies. [ABSTRACT FROM AUTHOR]

Background: Physical inactivity and excessive sedentary behavior (SB) are growing public health issues that require surveillance, guidelines, and targeted interventions. In addition to a variety of sophisticated technical methods, questionnaires are still an attractive method for quick, easy, comprehensive, and cost-effective estimation of SB. The aim of this study was to validate a modified version of the widely used Sedentary Behavior Questionnaire (SBQ) compared to waist-worn accelerometers as an objective measurement. Contemporary explanations covering the use of smart devices have been added to the original instrument, and sitting while handwriting was explicated in more detail. Methods: Cross-sectional data from an adult sample (n = 64, 20–85 y, 25 m, 39 f) were used in this first validation study. Based on prior investigations of the SBQ, analyses were conducted in a gender-specific manner. Criterion validity was assessed using Spearman's Rho coefficients. The Bland–Altman method was used to test the agreement between self-reported and accelerometer-measured SB time. Results: Using the modified SBQ (mSBQ), a significant gender difference in weekly sedentary time was found. Women estimated their sedentary time to be almost 50% higher than men (median 74.5 h vs. 51.0 h). No correlation was found between the questionnaire and accelerometer data for both subgroups (rho ≤ 0.281, p ≥ 0.174). Individual differences in daily SB estimation between both methods (in relation to accelerometry) were +3.82 h ± 4.36 h for women and +0.48 h ± 2.58 h for men (p < 0.001). Conclusion: The modifications to the SBQ did not improve the correlation between self-assessment of SB and objective determination. The reasons for the presented gender-specific overestimation of the participants' own sedentary time, which contradicts the findings of other studies, remain unclear and need to be investigated further. [ABSTRACT FROM AUTHOR]

Subtalar arthroereises (STA) is a minimally invasive and reversible surgery to correct symptomatic flexible flatfoot (FFF) in children. Various techniques were described either applying expandable sinus tarsi implants or lateral calcaneus stop screws. Studies comparing the outcome of STA with different devices are rare. This retrospective single-center cohort study analyzes the results of STA using three different implants. 113 STA were performed in 73 consecutive patients (28 females). Mean age at surgery was 10.8 years (range 5-16). Mean follow-up was 29.0 months (range 1-111). In 21 feet the non-absorbable Kalix® endorthesis and in 56 feet the absorbable Giannini endorthesis were applied. Subtalar extraarticular screw arthroereises (SESA) was conducted in 36 feet. Clinical, radiographic and pedobarographic parameters were analyzed. No intraoperative complications were observed. All three procedures achieved comparable improvements of the clinical, radiographic and pedobarographic parameters. The mean foot function index (FFI) improved from 36.4 (range 12-63) to 22.8 (range 2-55). The mean preoperative calcaneal inclination angle and the lateral talocalcaneal angle improved from 9.5° (range 0-22) and 42.3° (range 21-62) to 12.8° (range 0-26) and 37.6° (range 15-56), respectively. Pedobarographically determined values of the arch index, the medial midfoot contact area and the medial forefoot peak pressure decreased. In contrast to SESA (1/36, 3%), a higher incidence of implant-related complications was observed using Kalix® (6/21, 29%) and Giannini (10/56, 8%) sinus tarsi implants. Peroneal muscle contractures only occurred in the SESA group (4/36, 11%). Premature removal due to treatment-related complications was necessary in 6/21 Kalix® implants (29%), 4/56 Giannini implants (7%) and 4/36 SESA implants (11%). Implant choice for treatment of painful FFF in children with STA seems to play a subordinate role. Clinical, radiographic and pedobarographic outcomes are comparable between the applied implants. Surgeons and patients should be aware of the different spectrum of implant-related complications. Treatment can be reliably monitored by radiation-free pedobarography providing dynamic information about the deformity. [ABSTRACT FROM AUTHOR]

Simple Summary: Malignant bone and soft tissue tumors are usually surgically removed with an envelope of healthy tissue as a barrier. If located in the long bones of the upper and lower extremity, this approach leads to a large bone defect commonly affecting a joint. One way to rebuild the bone defect and the neighboring joint is the use of a megaprosthesis that is anchored in the remaining bone comparable to a conventional joint replacement. In general this approach is popular as it provides early stability and allows the affected patient to begin rehabilitation early on. However, complications leading to long-term unplanned reoperation are common. This article provides an overview of current implant survival, types of complication and long-term outcomes of megaprostheses used following tumor resection. Megaprosthetic reconstruction of segmental bone defects following sarcoma resection is a frequently chosen surgical approach in orthopedic oncology. While the use of megaprostheses has gained popularity over the last decades and such implants are increasingly used for metastatic reconstructions and in non-tumor cases, there still is a high risk of long-term complications leading to revision surgery. This article investigates current implant survivorship, frequency and types of complications as well as functional outcomes of upper and lower limb megaprosthetic reconstructions. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of radial extracorporeal shockwave therapy (rESWT) primarily on acute lumbar back pain (aLBP), and secondarily on physical function and quality of life. This randomized, placebo-controlled, single-blinded trial with 12-week follow-up (FU) randomized 63 patients with aLBP 1:1 into two groups receiving either rESWT (intervention) or sham rESWT (placebo) with a manipulated shockwave head not delivering any shockwaves. Both, rESWT and sham procedure were carried out eight times for four weeks. Both groups received additional analgesics and physiotherapy twice a week. Primary patient-reported outcome measure (PROM) was the visual analogue scale for aLBP (VAS-LBP). Secondary PROMs included the Oswestry disability index (ODI), Roland and Morris Disability Questionnaire (RDQ), EuroQol EQ-5D-3L, and the Beck Depression Index (BDI-II). Primary endpoint was a between-arm comparison of mean changes in VAS-LBP from baseline to final FU. At randomization, there were no differences between the two groups in relation to age and PROMs. Both groups showed significant improvement in all PROMs at final FU. VAS-LBP declined by 60.7% (p < 0.001) in the intervention and by 86.4% (p < 0.001) in the sham group. The intervention group showed significantly less pain relief after 4 and 12 weeks. The EQ-5D submodality pain showed significantly inferior results for the intervention (1.5 (0.58)) compared to the sham group (1.1 (0.33)) (p < 0.014) after eight weeks. No significant intergroup differences were observed for RDQ, ODI or BDI-II. Additional rESWT alongside conventional guideline therapy in aLBP does not have any significant effects on pain intensity, physical function, or quality of life. To the best of our knowledge, this is the first study with a high level of evidence reporting the efficacy of rESWT in aLBP treatment and will be a future basis for decision-making. [ABSTRACT FROM AUTHOR]

Simple Summary: The soft tissue reconstruction around proximal or total humeral megaprostheses following limb-sparing resection of a primary malignant bone tumor can be a challenge. A surgical technique to overcome these challenges is the Bateman-type soft tissue reconstruction, which is performed as a lateral acromion and trapezoid transfer aiming to improve soft tissue coverage and postoperative function. However, the functional outcome and the endoprosthetic complications of this procedure have hardly been evaluated. Our study shows that the Bateman-type reconstruction is a feasible treatment option, but the postoperative functional outcome is overall limited although good to excellent functional results can be achieved in individual patients. The risk for revision surgery is high within the first year, but remains low thereafter. We aimed to evaluate the functional outcome and endoprosthetic complications following the Bateman-type soft tissue reconstruction around proximal or total humeral replacements in patients undergoing resection of a primary malignant bone tumor. Between September 2001 and December 2018, a total of 102 patients underwent resection of a primary malignant bone tumor and subsequent reconstruction with a modular humeral megaprosthesis in our department. Fifteen (15%) of these patients underwent a Bateman-type soft tissue reconstruction and were included in this retrospective study. The median Musculoskeletal Tumor Society (MSTS) score was 21, the median Toronto Extremity Salvage Score (TESS) was 70, and the median American Shoulder and Elbow Surgeons (ASES) score was 72. Fifty-three percent (8/15) of all patients required a revision surgery after a median time of 6 months. There were 2 soft tissue failures, 3 infections and 3 tumor recurrences. The revision-free implant survivorship amounted to 53% (95% confidence interval (CI) 28–81) after 1 year and 47% (95% CI 22–73) at last follow-up. The Bateman-type reconstruction is a feasible option for soft tissue reconstruction but functional outcome is overall limited and the risk for revision surgery within the first postoperative year is high. [ABSTRACT FROM AUTHOR]

(1) Background: Modular megaprosthetic reconstruction using a proximal humerus replacement has emerged as a commonly chosen approach after bone tumor resection. However, the long-term risk for revision surgery is relatively high. One factor that might be associated with mechanical failures is periprosthetic osteolysis around the stem, also known as stress shielding. The frequency, potential risk factors, and the effect on implant survival are unknown. (2) Methods: A retrospective single-center study of 65 patients with sarcoma who underwent resection of the proximal humerus and subsequent reconstruction with a modular endoprosthesis. Stress shielding was defined as the development of bone resorption around the prosthesis stem beginning at the bone/prosthesis interface. The extent of stress shielding was measured with a new method quantifying bone resorption in relation to the intramedullary stem length. All patients had a minimum follow-up of 12 months with conventional radiographs available and the median follow-up amounted to 36 months. (3) Results: Stress shielding was observed in 92% of patients (60/65). The median longitudinal extent of stress shielding amounted to 14% at last follow-up. Fifteen percent (10/65) showed bone resorption of greater than 50%. The median time to the first radiographic signs of stress shielding was 6 months (IQR 3–9). Patients who underwent chemotherapy (43/65) showed a greater extent of stress shielding compared to those without chemotherapy. Three percent (2/65) of patients were revised for aseptic loosening, and one patient had a periprosthetic fracture (1/65, 1.5%). All these cases had >20% extent of stress shielding (23–57%). (4) Conclusions: Stress shielding of the proximal humerus after shoulder reconstruction with modular megaprosthesis is common. It occurs within the first year of follow-up and might be self-limiting in many patients; however, about one third of patients shows progression beyond the first year. Still, mechanical complications were rare, but stress shielding might be clinically relevant in individual cases. The extent of stress shielding was increased in patients who underwent perioperative chemotherapy. Stress shielding can be quantified with an easy method using the stem length as a reference. [ABSTRACT FROM AUTHOR]

The combination of 3D printing and navigation promises improvements in surgical procedures and outcomes for complex bone tumor resection of the trunk, but its features have rarely been described in the literature. Five patients with trunk tumors were surgically treated in our institution using a combination of 3D printing and navigation. The main process includes segmentation, virtual modeling and build preparation, as well as quality assessment. Tumor resection was performed with navigated instruments. Preoperative planning supported clear margin multiplanar resections with intraoperatively adaptable real-time visualization of navigated instruments. The follow-up ranged from 2–15 months with a good functional result. The present results and the review of the current literature reflect the trend and the diverse applications of 3D printing in the medical field. 3D printing at hospital sites is often not standardized, but regulatory aspects may serve as disincentives. However, 3D printing has an increasing impact on precision medicine, and we are convinced that our process represents a valuable contribution in the context of patient-centered individual care. [ABSTRACT FROM AUTHOR]

Simple Summary: Tumor endoprostheses are a common type of reconstruction after the resection of an extremity bone sarcoma. However, in the long-term, first and subsequent implant failures leading to revision surgery are common. One potential risk factor for implant failure is the length of surgery. This study investigates the impact of the length of surgery on prosthetic survival in 568 patients with sarcoma. Patients who had a first implant failure had a longer surgery; however, there were no differences in the infection-free survival, but only in the probability of mechanical failure. Patients with a subsequent revision surgery for infection had a shorter duration of surgery during the first revision. In conclusion, a shorter surgery appears beneficial; however, longer surgeries are not clearly associated with infection. In revision surgery, a longer operating time, indicating a more thorough debridement, may be desirable. Complications in megaprosthetic reconstruction following sarcoma resection are quite common. While several risk factors for failure have been explored, there is a scarcity of studies investigating the effect of the duration of surgery. We performed a retrospective study of 568 sarcoma patients that underwent megaprosthetic reconstruction between 1993 and 2015. Differences in the length of surgery and implant survival were assessed with the Kaplan–Meier method, the log-rank test and multivariate Cox regressions using an optimal cut-off value determined by receiver operating curves analysis using Youden's index. 230 patients developed a first and 112 patients a subsequent prosthetic failure. The median duration of initial surgery was 210 min. Patients who developed a first failure had a longer duration of the initial surgery (225 vs. 205 min, p = 0.0001). There were no differences in the probability of infection between patients with longer and shorter duration of initial surgery (12% vs. 13% at 5 years, p = 0.492); however, the probability of mechanical failure was higher in patients with longer initial surgery (38% vs. 23% at 5 years, p = 0.006). The median length of revision surgery for the first megaprosthetic failure was 101 min. Patients who underwent first revision for infection and did not develop a second failure had a longer median duration of the first revision surgery (150 min vs. 120 min, p = 0.016). A shorter length of the initial surgery appears beneficial, however, the notion that longer operating time increases the risk of deep infection could not be reproduced in our study. In revision surgery for infection, a longer operating time, possibly indicating a more thorough debridement, appears to be associated with a lower risk for subsequent revision. [ABSTRACT FROM AUTHOR]

Simple Summary: This single-center study is a retrospective review of 74 patients with primary aneurysmal bone cysts (ABCs). It aims to compare the three most common treatment options—intralesional curettage, the percutaneous instillation of polidocanol and en bloc resection. It is the first study comparing these three treatment options using MR scans for the evaluation of the treatment success of instillation therapy and demonstrates the superiority of MRI scans compared to conventional radiographs for cyst volume measurement. The study confirms the efficacy of polidocanol instillations for primary ABCs and justifies it as standard treatment option. However, in this study several instillations were found to be necessary to achieve complete healing or at least stable disease. In a relevant number of cases a conversion to a surgical treatment was necessary. Thus, in this study we relativize the so-far highly positive treatment results reported for instillations in the literature, and rate them skeptically. (1) Background: An aneurysmal bone cyst (ABC) is a benign, locally aggressive tumor. Different treatment modalities are described in the literature i.e., en bloc resection, intralesional curettage and percutaneous sclerotherapy. (2) Methods: This single-center study is a review of 74 patients with primary ABCs who underwent a surgical treatment or polidocanol instillation. Cyst volume measurements using MRI and conventional radiographs are compared. (3) Results: The mean pre-interventional MRI-based cyst volume was 44.07 cm3 and the mean radiographic volume was 27.27 cm3. The recurrence rate after intralesional curettage with the need for further treatment was 38.2% (13/34). The instillation of polidocanol showed a significant reduction of the initial cyst volume (p < 0.001) but a persistent disease occurred in 29/32 cases (90.6%). In 10 of these 29 cases (34.5%) further treatment was necessary. After en bloc resection (eight cases) a local recurrence occurred in two cases (25%), in one case with the need for further treatment. (4) Conclusions: MRI scans are superior to biplanar radiographs in the examination of ABCs. Sequential percutaneous instillations of polidocanol are equally effective in the therapy of primary ABCs compared to intralesional curettage. However, several instillations have to be expected. In a considerable number of cases, a conversion to intralesional curettage or en bloc resection may be necessary. [ABSTRACT FROM AUTHOR]

Simple Summary: Soft tissue sarcomas, a heterogenous group of tumors with a mesenchymal origin, are mostly located in the extremities and are commonly treated with surgery and radiotherapy. Using opportunities of reducing long-term therapy-related side effects in soft tissue sarcoma treatment is an important task for all physicians involved in soft tissue sarcoma treatment. The extent of lymph-sparing volume in adjuvant radiation therapy of extremity soft tissue sarcoma as a risk factor for lymphedema was analyzed in this study. Patients with a low lymph-sparing volume showed an increased risk of lymphedema in this retrospective study. Maximizing the potential oncologically justifiable lymph-sparing volume should be considered to reduce the risk of high-grade lymphedema when applying RT to extremities. Radiation therapy (RT) for extremity soft tissue sarcoma is associated with lymphedema risk. In this study, we analyzed the influence of lymph-sparing volume on the lymphedema occurrence in patients who received adjuvant extremity RT. The lymph-sparing quotient (LSQ) was calculated by dividing the lymph-sparing volume by the total extremity volume with double weightingfor the narrowest lymph-sparing region. A total of 34 patients were enrolled in this analysis. The median applied total radiation dose was 66.3 Gy in 36 fractions. Acute lymphedema appeared in 12 patients (35%). Most of them (n = 8) were lymphedema grade 1 and five patients had grade 2 to 3 lymphedema. Chronic lymphedema appeared in 22 patients (65%). 17 of these patients had at least a grade 2 lymphedema. In 13 of 14 patients with an LSQ ≤ 0.2 and 11 of 20 patients with an LSQ > 0.2, an acute or chronic lymphedema ≥ grade 2 was observed. A Kaplan–Meier Analysis of the two groups with the endpoint of a two-year lymph edema-free survival (=2-YLEFS) was estimated with an univariate, significant result (2-YLEFS LSQ ≤ 0.2 vs. LSQ > 0.2: 0% vs. 39%; p = 0.006; hazard ratio LSQ ≤ 0.2 vs. > 0.2 2-YLEFS 2.822 (p = 0.013); 95% confidence interval (CI): 1.24–6.42). Maximizing the potential oncologically-justifiable lymph-sparing volume should be considered to reduce the risk of high-grade lymphedema when applying RT to extremities. [ABSTRACT FROM AUTHOR]

This study examined whether an alignment of physical activity (PA) between osteoarthritis patients and their spouses, which was previously proven by accelerometry, might also be revealed by self-report. The PA of 28 cohabitating couples (58–83 years) was assessed by means of synchronous accelerometry (ActiGraph wGTX3-BT) and compared to their according self-reports in the German Physical Activity, Exercise, and Sport Questionnaire (BSA-F). Both methods were used to quantify the average weekly light PA, moderate to vigorous PA (MVPA), and total PA. Accelerometry revealed no differences in weekly light PA and total PA (p ≥ 0.187) between patients and spouses, whereas the patients' spouses accumulated significantly more MVPA (p = 0.015). In contrast, the self-report did not reveal any differences between the two groups in terms of PA (p ≥ 0.572). Subsequent correlation analyses indicated that accelerometry data for mild PA and total PA were significantly correlated in couples (r ≥ 0.385, p ≤ 0.024), but MVPA was not (r = 0.257, p = 0.097). The self-reported PA data, on the other hand, did not indicate any significant correlation (r ≤ 0.046, p ≥ 0.409). The presented results give a first indication that an alignment of PA between osteoarthritis patients and their spouses is most likely to be detected by accelerometry, but not by self-report. [ABSTRACT FROM AUTHOR]

The need for concomitant proximal fibular epiphysiodesis (PFE) when correcting leg length discrepancy (LLD) with temporary proximal tibial epiphysiodesis (PTE) in children is controversially discussed. This single center, retrospective cohort study analyzes proximal fibular growth in patients treated by PTE with and without concomitant PFE. Radiographic measurements were conducted before implantation and at implant removal. The position of the fibular head in relation to the tibia was assessed with recently established radiographic reference values. All patients (n = 58, 19 females) received PTE to treat LLD at a mean age of 12.2 years (range 7 to 15). In 27/58 (47%) concomitant PFE was performed. Mean follow-up was 36.2 months (range 14.2 to 78.0). The position of the proximal fibula at implant removal was within physiological range in 21/26 patients (81%) with PFE and in 21/30 patients (70%) without PFE. Proximal fibular overgrowth newly developed in 2/26 patients (8%) treated with PFE and in 5/30 patients (17%) treated without PFE (p = 0.431). Peroneal nerve injury or discomfort due to proximal fibular overlength was not reported. The position of the proximal fibula should be critically assessed preoperatively under consideration of reference values before PTE. In consequence of this study, the authors do not routinely perform PFE concomitantly with PTE for correction of moderate LLD in children if the proximal fibula is localized within physiological radiographic margins determined by the established reference values. [ABSTRACT FROM AUTHOR]

Background: Periprosthetic shoulder infections are devastating complications after shoulder arthroplasty. A potential treatment concept is a two-stage prosthesis exchange. Data are sparse in terms of clinical outcome, including infection-free survival and patient satisfaction after this procedure. In the present study, we investigated recurrence of infection, revision-free survivorship and clinical outcome following two-stage revision due to periprosthetic shoulder infection. Furthermore, reasons for poor outcome were analyzed. Methods: Sixteen patients undergoing two-stage revision after shoulder joint infection were retrospectively identified. Recurrence of infection was analyzed by Kaplan–Meier survival curve. Clinical outcome was quantified with subjective shoulder value (SSV), "quick" Disabilities of the Arm, Shoulder and Hand (qDASH) and Rowe score. Range of motion (ROM) was measured pre- and postoperatively. Postoperative scores and ROM were compared in a subgroup analysis according to different reimplanted prosthesis types. Results: The reinfection-free implant survival was 81% after one year and at final follow-up (FU; mean of 33.2 months). The overall revision-free survival amounted to 56% after one year and at final FU. Patients who received reverse shoulder arthroplasty (RSA) as part of reimplantation had less disability and long-term complications. This group demonstrated better subjective stability and function compared to patients revised to megaprostheses or large-head hemiarthroplasties. Conclusions: Two-stage revision following periprosthetic joint infection of the shoulder allows appropriate infection control in the majority of patients. However, the overall complications and revision rates due to mechanical failure or reinfection are high. Reimplantation of RSA seem superior to alternative prosthesis models in terms of function and patient satisfaction. Therefore, bone-saving surgery and reconstruction of the glenoid may increase the likelihood of reimplantation of RSA and potentially improve outcome in the case of infection-related two-stage revision of the shoulder. [ABSTRACT FROM AUTHOR]

Treatment of congenital pseudarthrosis of the tibia remains a major challenge in pediatric orthopedics. Ideal timing and preference of surgical procedures are discussed controversially. A variety of reconstructive treatment strategies have been described in literature, but so far none has proven its superiority. The aim of treatment is to obtain long-term bone union, to prevent refracture, and to correct angular deformities and leg length discrepancies. This study retrospectively evaluates the outcome of different reconstructive strategies. Sixty-nine patients were identified who presented to our outpatient department between 1997 and 2019. Twenty-six of these patients underwent reconstructive surgical treatment and were included in this study. The study cohort was divided into three groups. Excision of the pseudarthrosis was performed in all patients in Group A and B, and in two patients of Group C. Group A (six/26 patients) received subsequent bone transport through external fixation maintaining original length. In Group B (15/26 patients), patients underwent either previous, simultaneous, or subsequent extrafocal lengthening through external fixation to reconstitute length. In Group C (five/26 patients), internal fixation with intramedullary nails was applied. Radiological and clinical evaluation was performed to assess bone union and complication rates. Results varied considerably between the study groups. Overall, the primary bone fusion rate was 69.2%. There were four refractures, all occurring in Group B. The long-term bone union rate without refracture was 53.8%. The overall complication rate was 53.8% and 23.1% showed persistent pseudarthrosis. Two secondary amputations were performed due to failed bone fusion. In conclusion, excision of the pseudarthrosis and extrafocal lengthening achieves a satisfying bone union rate and limb reconstruction, while bone transport does not offer significant advantages but shows higher complication rates. Intramedullary stabilization should be applied to maintain bone union, but shows lower bone union rates when used as a stand-alone treatment regimen. Regardless of the primary bone fusion rates, the probability of long-term bone union remains unpredictable. [ABSTRACT FROM AUTHOR]

Background—Postoperative serum C-reactive protein (CRP) is an important diagnostic parameter for systemic inflammation and reflects surgical trauma. While trends and normal trajectories after total knee (TKA) or hip arthroplasty (THA) are established, there is no reference standard for shoulder arthroplasty (SA). Therefore, the aim of this study was to research CRP trends and influencing factors following SA. Methods—This retrospective study analyzed postoperative serum CRP levels and trajectories in 280 patients following SA. Influence of prosthesis design, sex, operating time, BMI, and humeral augmentation with bone cement were analyzed using descriptive statistics and (non-) parametric testing. Results—There is a CRP trend with a peak on day two or three, with a subsequent decrease until day seven. Reverse and stemmed prostheses show a statistically higher CRP peak than stemless prostheses or hemiarthroplasties (HA). There was no influence of gender, body mass index (BMI), operating time, or bone cement. Conclusion—The presented findings may contribute to a better understanding of the postoperative CRP course after SA. The results of this retrospective study should be validated by a prospective study design in the future. [ABSTRACT FROM AUTHOR]

Introduction: D-dimer is a diagnostic criterion for periprosthetic joint infection (PJI) of the Musculoskeletal Infection Society (MSIS) in 2018. The aim of this study was to evaluate the serum D-dimer values in comparison to C-reactive protein (CRP) and interleukin-6 (IL-6) for the diagnosis of PJI. Materials and Methods: We included 119 patients (50 women, 69 men; 71 knees, 48 hips) undergoing revision arthroplasty with preoperative assessment of CRP, IL-6, and serum D-dimer. Cases were classified as infected or aseptic based on the MSIS criteria of 2018. Receiver operating curves and Youden's index were used to define an ideal cut-off value and sensitivity and specificity for the individual parameters, and respective combinations were calculated using cross-tables. Results: The median D-dimer level (2320 vs. 1105 ng/mL; p < 0.001), the median CRP level (4.0 vs. 0.5 mg/dL; p < 0.001), and the median IL-6 level (21.0 vs. 5.0 pg/mL; p < 0.001) were significantly higher in the group of PJI compared to the group with aseptic failure. The calculated optimal cut-off values were 2750 ng/mL (AUC 0.767) for D-dimer, 1.2 mg/dL (AUC 0.914) for CRP, and 10.0 pg/mL (AUC 0.849) for IL-6. D-dimer showed a sensitivity of 38% and specificity of 94%, whereas the CRP and IL-6 had sensitivities of 88% and 76%, and specificities of 87% and 92%, respectively. Conclusion: In comparison with CRP and IL-6, serum D-dimer showed low sensitivity and specificity in our cohort. While CRP and IL-6 combination had the highest sensitivity, a combination of Il-6 and D-dimer or CRP and IL-6 had the highest specificity. [ABSTRACT FROM AUTHOR]

Objective: To compare the habitual sedentary behavior (SB) and physical activity (PA) of older hip osteoarthritis patients before and after elective arthroplasty. Methods: SB, PA and joint-specific disability of 16 patients (68.9 ± 6.8 years) were assessed by accelerometry and questionnaires before and 9 months after arthroplasty. Results: All patients reported substantial postoperative improvements of their joint-related complaints (p ≤ 0.001). Accelerometry showed changes in neither daily SB (10–60 min sedentary bouts, p ≥ 0.569) nor in PA (steps, time in mild-to-vigorous activity and energy expenditure, p ≥ 0.255). Correlation analyses revealed that patients with severe preoperative disability showed a decrease in sedentary time, which was the opposite in patients with mild preoperative disability. Conclusion: SB and PA do not necessarily change after arthroplasty in older orthopedic patients. Even longer bouts of uninterrupted sitting, which are detrimental to health, do not decrease. Preoperative patient education is recommended to foster behavioral changes following elective arthroplasty. [ABSTRACT FROM AUTHOR]

The widespread prevalence of periprosthetic joint infections (PJIs) poses significant challenges in orthopedic surgeries, with pathogens such as Staphylococcus epidermidis being particularly problematic due to their capability to form biofilms on implants. This study investigates the efficacy of an innovative silver nitrate-embedded poly-L-lactide biopolymer coating designed to prevent such infections. The methods involved applying varying concentrations of silver nitrate to in vitro setups and recording the resultant bacterial growth inhibition across different serum environments, including human serum and various animal sera. Results highlighted a consistent and significant inhibition of S. epidermidis growth at all tested concentrations in each type of serum without adverse interactions with serum proteins, which commonly compromise antimicrobial efficacy. This study concludes that the silver nitrate-embedded biopolymer coating exhibits potent antibacterial properties and has potential for use in clinical settings to reduce the incidence of PJIs. Furthermore, the findings underscore the importance of considering serum interactions in the design and testing of antimicrobial implants to ensure their effectiveness in actual use scenarios. These promising results pave the way for further research to validate and refine this technology for clinical application, focusing on optimizing silver ion release and assessing biocompatibility in vivo.