Background: Evidence regarding the effects of twisting hamstring tendons on graft properties in anterior cruciate ligament (ACL) reconstruction remains controversial. The objective of this study was to evaluate the influence of a 180° twist on the tensile properties of human hamstring tendon grafts (HTGs). Methods: Fourteen human cadavers were included, and hamstring tendons (semitendinosus [ST] and gracilis [GR]) were harvested bilaterally. Matched pairs of tendons were allocated to the ST and GR groups and further subdivided into control (ST-0, GR-0) and experimental (ST-180, GR-180) subgroups. Standard tripled single-tendon grafts were prepared in the control groups, while grafts in the experimental groups were twisted by 180°. All grafts were preconditioned and tested using a universal testing machine (Shimadzu AGS-X, Shimadzu Corporation, Japan) to determine tensile strength, stiffness, tensile modulus, and energy absorption capacity. Results: In the semitendinosus group, the maximum force was 648.72 (±287.71) N for ST-0 and 853.11 (±189.14) N for ST-180, with energy absorption capacities of 9.21 (±4.47) J and 13.48 (±4.95) J, respectively. Although the mean values of the investigated parameters were consistently higher in the ST-180 group, these differences did not reach statistical significance. In the gracilis group, no statistically significant differences were observed between the GR-0 and GR-180 subgroups for any parameter. Conclusions: Twisting hamstring tendons by 180° during graft preparation results in limited alterations of biomechanical properties, without statistically significant improvements. These findings call into question the clinical relevance of this technique in enhancing graft material properties for ACL reconstruction.

Background and Objectives: It is unknown whether the tibial tuberosity–tibial intercondylar midpoint (TT–TIM) distance can be interchangeably measured on axial computed tomography (CT) and magnetic resonance imaging (MRI). The objective of this retrospective cross-sectional comparative study was to evaluate the intermethod agreement of the TT–TIM distance on axial CT and MRI and its bias towards tibial rotation (TR), age, sex, and body side. Materials and Methods: On axial CT and MRI of 15 consecutive knee pairs where each pair belonged to the same patient with no pathology affecting the tibial circumference and tibial tuberosity, TT–TIM distance and TR were measured by two blinded radiologists at 2-week intervals. Upon checking the symmetry of distributions (Shapiro–Wilk test), differences between matched knee pairs (Wilcoxon signed-rank test), intermethod (Bland–Altman plot) and interrater agreement (intraclass correlation coefficient [ICC]), and correlations (Spearman rank correlation) were assessed. Results: The mean intermethod difference in TT–TIM distance was not statistically significant (−0.4 mm [−1.82, 0.96]; p = 0.52). The TT–TIM distance did not differ between knee pairs (p = 0.68), its interrater agreement was almost perfect (ICC > 0.81), and no bias towards TR (p > 0.66), age (p > 0.14), sex (p = 0.66), and body side (p > 0.37) was found. Conclusions: The TT–TIM distance can be interchangeably measured on axial CT and MRI with almost perfect interrater agreement, unbiased towards TR, age, sex, and body side.

Objectives: Materials with ceramic surface treatments have been adopted in total knee arthroplasty (TKA) to limit polyethylene wear and thus extend implant longevity. This study evaluated, at a single center, mid-term survivorship and clinical outcomes for a mobile-bearing knee prosthesis with a titanium–niobium nitride (TiNbN) coating. Methods: A total of 150 patients who underwent primary cemented TKA using the same TiNbN-coated mobile-bearing prosthesis were identified through the institutional database. Of these, 102 patients (102 knees) attended the follow-up examination and provided informed consent to participate in this study. All patients underwent comprehensive clinical and radiological assessment. Primary outcomes were the Forgotten Joint Score (FJS) and the Knee Injury and Osteoarthritis Outcome Score (KOOS). Results: After a mean follow-up period of 7.9 years, two revision surgeries were recorded. One revision was performed due to late periprosthetic joint infection, while the other involved synovectomy and liner exchange due to persistent stiffness and pain. At 9 years follow-up, overall survivorship of the TiNbN-coated TKA was 97.1% (95% CI, 88.4–99.3%). Mean FJS and KOOS were 70.0 (range 29–100) and 70.6 (range 24–98), respectively. No sex-based differences were detected in clinical outcomes or implant survivorship. Conclusions: The TiNbN-coated mobile-bearing knee prosthesis demonstrated favorable mid-term survivorship and patient-reported outcomes. These findings support its use as a treatment option for knee osteoarthritis, with performance comparable to contemporary TKA designs.

The purpose of this study was to evaluate the 4-year survivorship of total knee arthroplasty (TKA) of a single manufacturer and determine whether failure rates differ between the cruciate-retaining (CR) and the posterior-stabilised (PS) type of impla...

Background and Objectives: To validate a computed tomography (CT) measure of tendon yaw (TY) and determine its diagnostic specificity, precision, and clinical relevance in recurrent patellar instability (RPI) in comparison with standard imaging tests (SIT1, SIT2), femoral trochlear dysplasia (FTD), and vastus medialis obliquus (VMO) morphology. Materials and Methods: This retrospective cross-sectional study included 113 subjects (187 knees) examined using a standardized CT protocol for RPI following strict exclusion criteria. TY, SIT1, and SIT2 were measured using predefined axial landmarks. VMO cross-sectional area was assessed at three standardized levels. Diagnostic performance, measurement precision, and interrater agreement were evaluated. Results: TY significantly distinguished recurrent dislocators from nondislocators (p = 0.003) and was independent of age, sex, laterality, and femoral, tibial, or knee rotation (p ≥ 0.42). A threshold of ≥22° demonstrated high diagnostic specificity (92%; 95% CI, 85–97%), with a normal cutoff defined as ≤12°. Measurement precision was approximately 90%. SIT1 and SIT2 were influenced by femoral and knee rotation but not tibial rotation. All imaging tests were associated with FTD (p < 0.0001). No significant correlation was found between any imaging test and VMO area, although VMO was reduced in recurrent dislocators and in women. Conclusions: TY is a direct and highly specific CT measure of extensor mechanism yaw (z-axis rotation) that avoids indirect osseous and soft-tissue surrogates, supporting confirmatory diagnostic assessment and preoperative planning in RPI.