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Background/Objectives: Musculoskeletal aging can clinically hardly be distinguished from degenerative disease, especially if symptoms are nonspecific, like lower back pain and reduced physical resilience. However, age-related changes are considered to be physiological until they cause osteoporotic fractures or sarcopenia-related restrictions. This radio-anatomic investigation examines whether findings in lumbar magnetic resonance imaging (MRI) mirror age- and sex-related musculoskeletal differences that help to identify the onset of sarcopenia. Methods: Lumbar MRI investigations from 101 women and 101 men were retrospectively evaluated for vertebral and muscular cross-sectional diameter sizes and T2-signal intensities ("T2-brightness") in axial sections in the L5-level. The results were correlated with the individual's age to find specific alterations that were indicative of sarcopenia or attributable to the aging process. Results: In women (average age 62.6 (34–85) years), musculoskeletal cross-sectional area sizes and diameters were significantly smaller (p < 0.00001) compared to those in men (average age 57.0 (21–90) years). The most pronounced structural age-related change was the increasing mean posterior paravertebral muscle brightness (MPPVB), which exceeded the mean vertebral brightness (MVB) earlier and to a greater extent in women than in men (p < 0.00001). The brightness difference (∆MVB − MPPVB) was found to indicate (pre-)sarcopenia at values below 25. Conclusions: Significant age-related deterioration in muscle quantity and quality was more obvious in women, correlated with the onset of menopause, and progressed to lower levels during aging. [ABSTRACT FROM AUTHOR]

Changes in lower limb alignment after open‐wedge high tibial osteotomy (owHTO) influence joint kinematics. The aim of this study was to investigate the morphological and kinematic changes of the knee joint, in particular the patellofemoral joint, using a multibody simulation model. OwHTO with an open tibial wedge of 6–12 mm (1 mm intervals) was virtually performed on each of 13 three‐dimensional (3D) computer‐aided design models (CAD models) derived from computer tomography scans of full‐leg cadaver specimens. For each owHTO, an individual biomechanical simulation model was built and knee flexion from 5° to 100° was simulated using a multibody simulation model of the native knee. Morphologic and alignment parameters as well as tibiofemoral and patellofemoral kinematic parameters were evaluated. Almost linear changes in tibial tuberosity trochlea groove (TT‐TG) (0.42 mm/1 mm wedge height) were observed which led to pathological values (TT‐TG > 20 mm) in 3 out of 13 knees. Furthermore, a 6 mm increase in osteotomy wedge height increased lateral patellofemoral rotation by 0.8° (range: 0.39° to 1.11°) and led to a lateral patellar translation of 0.8 mm (range: 0.37–3.11 mm) on average. Additionally, valgisation led to a medial translation of the tibia and a decrease in the degree of tibial internal rotation during knee flexion of approximately 0.3°/1 mm increase in osteotomy wedge height. The increase in TT‐TG and the biomechanical effects observed influence patellofemoral tracking, which may increase retropatellar pressure and are potential risk factors for the development of anterior knee pain. [ABSTRACT FROM AUTHOR]

Background: The aim of our study was to examine the combined effects of tranexamic acid (TXA) and vancomycin powder (VP) on chondrocytes in vitro. Despite the use of TXA and VP being linked to a reduced risk of extensive postoperative blood loss and periprosthetic joint infections (PJIs) in TKA, the possible cytotoxic side effects on periarticular cell types remain unclear. Methods: Human chondrocytes were harvested from hyaline cartilage and expanded in monolayer culture before being simultaneously exposed to different concentrations of TXA and VP for varying exposure times. Cell viability and proliferation were assessed using an ATP assay and an Annexin 5 assay, respectively, while changes in the relative expression of chondrogenic marker genes were examined using semiquantitative RT-PCR. Results: The simultaneous exposure of chondrocytes to TXA and VP for more than 48 h led to a reduction in both cell viability and proliferation rates. When exposing chondrocytes to the lowest examined concentrations of both TXA (10 mg/mL) and VP (3 mg/mL), the observed effects were delayed until 96 h. However, our study found no dependencies of the observed effects on the concentrations tested. Further, we found no effects on the expression of chondrogenic marker genes. Conclusions: Consequently, limiting the exposure time of chondrocytes to TXA and VP in an in vitro setting to 24 h may be considered safe and could help to further improve the understanding of the safe use of substances in vivo. However, further in vitro research is required to develop a comprehensive understanding of the effects of both VP and TXA on important periarticular cell types in TKA, including chondrocytes, osteocytes, and tenocytes. [ABSTRACT FROM AUTHOR]

Background: Anterior knee pain is a prevalent issue post total knee arthroplasty, often necessitating revision surgery. Various factors contribute to this complication, including patellar maltracking and excessive patellofemoral load. Kinematic alignment has emerged as an alternative, showing promising outcomes in clinical studies. However, its impact on patellofemoral biomechanics needs to be more adequately understood. This study compared the effects of kinematically versus mechanically aligned total knee arthroplasty on patellofemoral joint biomechanics. Methods: Eight fresh-frozen human knee specimens underwent biomechanical testing in a knee rig setup, performing an active weight-loaded knee joint flexion of 30–130°. After the testing of native kinematics, kinematically and mechanically aligned total knee arthroplasty was performed using a medial pivot implant design without patellar resurfacing. Quadriceps force, retropatellar peak pressure and the retropatellar contact area were measured during knee flexion using a patellar pressure-sensitive film. Patella kinematics (shift and tilt) was tracked using an optoelectrical measurement system. Functional regressions were used to determine the influence of the alignment on the kinematics and loading of the knee joint. Results: Kinematically aligned total knee arthroplasty resulted in reduced quadriceps force during knee flexion compared to mechanically aligned total knee arthroplasty. Retropatellar peak pressure, retropatellar contact area and patella kinematics did not vary between the alignments. Conclusions: Kinematic alignment offers potential benefits in reducing quadriceps force during knee flexion, which may mitigate anterior knee pain risk. Further research is needed to elucidate its effects in varying anatomical conditions and alignment strategies. [ABSTRACT FROM AUTHOR]

This work focuses on combating bacterial infections in bone tissue using metal elements embedded in bioactive glass. While there is an urgent need for alternative methods with a shrinking number of effective treatment options untouched by antimicrobial resistance, it is crucial to first understand the mechanisms of pathogenesis, persistence, and bacterial resistance in skeletal infection, and then develop effective counterstrategies and innovative alternatives. This review considers the role of antimicrobial metal ions, their mechanism of action, and their incorporation into bioactive glass formulations as these materials can serve as delivery platforms with the least possible complexities. Furthermore, the bacterial infection risk in bone is also examined with specific attention to antibiotic resistance and biofilm formation. This review sheds light on the most promising materials as novel antibacterial agents by presenting a wide range of possible bioactive glass formulations equipped with potential antibacterial ions and in vitro/ in vivo insights, and it also reinforces the importance of continuing studies to develop multi‐faceted antibacterial bioactive glasses. [ABSTRACT FROM AUTHOR]

Introduction: Surgical site infections (SSI) are one of the most common complications after extensive sarcoma resections and represent a daily challenge. SSI occur in up to 50% of cases particularly in the peripelvic area. One possible approach to reduce infection rate is perioperative antibiotic prophylaxis. The aim of this study therefore was to investigate the influence of perioperative antibiotic prophylaxis on the infection rate and the possible influence of location-specific antibiotic prophylaxis with ampicillin/sulbactam. Methods: This monocentric retrospective study included 366 patients who underwent sarcoma resections in the groin, proximal thigh, or gluteal region. All patients were operated on by 2 surgeons after neoadjuvant pretreatment if necessary. 3 groups of patients were defined. Group 1: In 60.4% of all cases, antibiotic prophylaxis was administered with cephalosporins (also clindamycin in case of penicillin allergy). Group2: In 9.8% of cases, ampicillin/sulbactam was used. Group 3: 29.8% of patients did not receive any antibiotic prophylaxis. Results: In 31.1% of treated cases, antibiotic therapy was prolonged due to extended tumor resections. Postoperative infections occurred in 23.2% (85 cases), in 77 cases within the first 90 days (on average after 20 days). The median operating time, blood loss was higher, and tumor size were significantly larger in cases with infections, compared to patients without infection. In group 1 and 2 with perioperative single-shot prophylaxis, infection occurred in 24.1% of cases, compared to 13.5% of cases without prophylaxis (group 3) (p= 0.032). In the patients with prolonged antibiotic therapy, infection occurred in 31.6% of cases, compared to 16.3% of cases without prolongation (p< 0.001). In the group 2, infection occurred in 19.4% of cases compared to 24.9% of cases in the group 1 (p= 0.479). In the multivariate analysis, surgery time longer 80 min, blood substitution, neoadjuvant radio- and chemotherapy proved to be a risk factor for SSI. Discussion: Region adapted perioperative antibiotic prophylaxis may reduce the risk of infection after extended sarcoma resection in the peripelvic area. However, the particular bacterial spectrum of this anatomic region should be taken into account when deciding which antibiotics to use. [ABSTRACT FROM AUTHOR]

Purpose: The surgical management of periprosthetic femoral fractures is particularly challenging in geriatric patients due to physiological limitations. The choice between open reduction and internal fixation (ORIF) and hip revision arthroplasty for treating Vancouver B2 and B3 fractures remains controversial. This study aims to contribute further evidence by analyzing the in-hospital outcomes in geriatric patients with Vancouver B2/3 fractures. Methods: This retrospective study analyzed 133 patients treated for Vancouver B2/3 fractures at a level I trauma center from 2017 to 2023. Data were collected on preclinical characteristics, comorbidities, Vancouver classification, surgery-related parameters, and postoperative outcomes for an age- and gender-matched analysis. A subgroup analysis was also conducted on patients classified as American Society of Anesthesiologists (ASA) class 3 and 4. Results: Among the 133 patients, 85 suffered Vancouver B2 fractures and 48 Vancouver B3 fractures. Age-and-gender-matched analysis revealed that ORIF was more commonly performed in patients with higher ASA grades. A subgroup analysis of ASA 3 and 4 patients and an age-and-gender-matched analysis showed that ORIF resulted in shorter operation times and less blood loss. No significant differences were found in mortality or complication rates. Conclusions: ORIF is associated with shorter operation times, less bleeding, and comparable in-hospital outcomes in treating Vancouver B2/3 fractures in higher-risk geriatric patients compared to revision arthroplasty. The retrospective design and small sample size in the ORIF group are limitations of the study. Further studies with functional evaluation are still required. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the fracture patterns and complexity of distal humerus fractures with high-resolution computed tomography (CT) as a function of Dual-Energy X-ray absorptiometry (DXA)-derived bone marrow density (BMD) measurements in an elderly patient cohort. Methods: A retrospective chart review was conducted on patient data collected at a Level I trauma center between January 2007 and January 2022. Inclusion criteria comprised patients aged ≥40 years with a confirmed distal humerus fracture as demonstrated by CT. Additionally, patients were included if they underwent DXA. Patient demographics and detailed information regarding the surgical treatment and trauma mechanism were retrieved from the institutional databank. Fractures were classified as either 'low-plane' distal humeral fractures or 'non-low-plane' distal humerus fractures. Furthermore, the fracture patterns were classified according to established classification systems. Intra- and postoperative complication and revision rates were analyzed. Results: A total of 41 patients (30 women; mean age 74 ± 13 years) were enrolled. Low-energy trauma was sustained by 68% of the patients. The remaining 32% of the fractures involved medium-energy trauma. A total of 62% of the patients underwent primary osteosynthesis, while 30% of patients were initially treated with an external fixator. ORIF was performed in 89% of cases and, in the majority, double-plate osteosynthesis was used (76%). An olecranon osteotomy was performed in 30% of cases. A total of 5% of cases received total elbow arthroplasty, and 10% of cases were treated conservatively. A total of 61% of patients had osteoporosis, 24% of patients had osteopenia, and 15% of patients had a normal BMD with an overall mean T-score of −2.4. Most of the fractures were complex (including 61% Type C fractures). A total of 66% of cases were considered as 'low-plane' fractures. Postoperative complications occurred in 11% of patients (64% of cases among 'low-plane' fractures). Revision surgery was required in 20% of cases. Conclusions: The consecutive series of patients showed a high incidence of 'low-plane' fractures. However, no statistical significance was found between the BMD and fracture complexity. The very distal 'low-plane' fractures showed a high complication rate, which was aggravated by osteoporotic bone conditions. These findings highlight the need for future research with larger patient samples to better understand the relationship between the BMD, fracture complexity, and outcomes in patients with 'low-plane' fractures in order to reduce complications and improve clinical outcomes. [ABSTRACT FROM AUTHOR]

Objective: The direct anterior approach (DAA) is a recognized technique for total hip arthroplasty (THA) that spares soft tissue. Functional and clinical outcomes following THA via the DAA in patients with complex acetabular deformities, specifically coxa profunda (CP) and protrusio acetabuli (PA), have yet to be determined. Methods: A retrospective analysis was conducted on 188 primary THA cases, including 100 CP hips and 88 PA hips, performed via the DAA. Functional and clinical outcomes were evaluated by means of the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Harris Hip Score (HHS) preoperatively and at a mean follow-up of 46 ± 14 months. Furthermore, potential complications were assessed. Results: From the preoperative to the latest postoperative visit, a significant improvement in the WOMAC total score was observed (CP: −34.89 ± 20.66; PA: −40.38 ± 21.11). The length of stay (LOS) was the only parameter predictive of the postoperative WOMAC total score, with each day of LOS increasing the postoperative WOMAC by a mean of 1.77 points (p < 0.01). The HHS improved by 38.37 ± 14.23 (PA-group) and 32.79 ± 14.89 points (CP-group). No significant difference in the patient-reported outcome measures (PROMs) between the CP- and PA-group was found. The survival rate for any revision was 97.70% (PA-group) and 92.80% (CP-group). Conclusion: The results of this study indicate that the minimally invasive DAA was not predictive of the functional and clinical outcome following DAA-THA in patients with CP and PA. Improvements in the mean WOMAC and HHS scores were above or within the reported MCID. Additionally, revision rates were well below those reported in the literature for short and intermediate follow-up periods. [ABSTRACT FROM AUTHOR]

Introduction: Arthrodesis of a (diseased) ankle joint is usually performed to achieve pain relief and stability. One basic principle of arthrodesis techniques includes rigid fixation of the surfaces until union. It seems plausible that stable anchoring and homogeneous pressure distribution should be advantageous, however, it has not been investigated yet. The aim is to achieve uniform compression, as this is expected to produce favorable results for the bony fusion of the intended arthrodesis. Numerous implants with different biomechanical concepts can be used for ankle fusion. In this study, headless compression screws (HCS, DePuy Synthes, Zuchwil, Switzerland) were compared biomechanically to an alternative fixation System, the IOFix device (Extremity Medical, Parsippany, NJ, USA) in regard to the distribution of the compression force (area of contact) and peak compression in a sawbone arthrodesis-model (Sawbones® Pacific Research Laboratories, Vashon, WA, USA). This study aims to quantify the area of contact between the bone interface that can be obtained using headless compression screws compared to the IOFix. In current literature, it is assumed, that a large contact surface with sufficient pressure between the bones brings good clinical results. However, there are no clinical or biomechanical studies, that describe the optimal compression pressure for an arthrodesis. Material and methods: Two standardized sawbone blocks were placed above each other in a custom-made jig. IOFix and headless compression screws were inserted pairwise parallel to each other using a template for a uniform drilling pattern. All screws were inserted with a predefined torque of 0.5 Nm. Pressure transducers positioned between the two sawbone blocks were compressed for the measurement of peak compression force, compression distribution, and area of contact. Results: With the IOFix, the compression force was distributed over significantly larger areas compared to the contact area of the HCS screws, resulting in a more homogenous contact area over the entire arthrodesis surface. Maximum compression force showed no significant difference. Conclusion: The IOFix system distributes the compression pressure over a much larger area, resulting in more evenly spread compression at the surface. Clinical studies must show whether this leads to a lower pseudarthrosis rate. [ABSTRACT FROM AUTHOR]

Background/Objectives: Magnetic resonance imaging (MRI) is the preferred diagnostic means to visualize spinal pathologies, and offers the possibility of precise structural tissue analysis. However, knowledge about MRI-based measurements of physiological cross-sectional musculoskeletal dimensions and associated tissue-specific average structural brightness in the lumbar spine of healthy young women and men is scarce. The current study was planned to investigate characteristic intersexual differences and to provide MRI-related musculoskeletal baseline values before the onset of biological aging. Methods: At a single medical center, lumbar MRI scans of 40 women and 40 men aged 20–40 years who presented with moderate nonspecific low back pain were retrospectively evaluated for sex-specific differences in cross-sectional sizes of the fifth lumbar vertebrae, psoas and posterior paravertebral muscles, and respective sex- and age-dependent average brightness alterations on T2-weighted axial sections in the L5-level. Results: In women (mean age 33.5 years ± 5.0 (standard deviation)), the investigated musculoskeletal cross-sectional area sizes were significantly smaller (p < 0.001) compared to those in men (mean age 33.0 years ± 5.7). Respective average musculoskeletal brightness values were higher in women compared to those in men, and most pronounced in posterior paravertebral muscles (p < 0.001). By correlating brightness results to those of subcutaneous fat tissue, all intersexual differences, including those between fifth lumbar vertebrae and psoas muscles, turned out to be statistically significant. This phenomenon was least pronounced in psoas muscles. Conclusions: Lumbar musculoskeletal parameters showed significantly larger dimensions of investigated anatomical structures in men compared to those in women aged 20–40 years, and an earlier onset and faster progress of bone loss and muscle degradation in women. [ABSTRACT FROM AUTHOR]