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Purpose: To determine if trochlear morphology in healthy knees depends on sex and ethnicity, and to compare it to off-the-shelf TKA prostheses., Methods: Three retrospective series of CT angiograms from France (female, 124; male, 135), China (female, 122; male, 137) and South Africa (female, 21; male, 62) were used to digitize osseous landmarks at the level of the femoral epicondyles. Sulcus angle, trochlear rotation, lateral trochlear inclination, trochlear asymmetry ratio, and trochlear depth index were quantified for each knee and for 10 total knee arthroplasty (TKA) models. Univariable regression analyses were performed to determine associations of the five trochlear parameters with sex and ethnicity. Interquartile ranges (IQR) of native trochlear parameters were compared to the trochlear parameters of 10 off-the-shelf TKA prostheses., Results: Compared to French knees, Chinese knees had greater sulcus angle (β = 6.3°, p < 0.001), trochlear rotation (β = 0.8°, p = 0.004) and trochlear depth index (β = 1.60, p < 0.001). Conversely, South African knees had greater trochlear rotation (β = 1.9°, p < 0.001) and lateral trochlear inclination (β = 3.7°, p < 0.001). Female knees had smaller trochlear asymmetry ratios (β =  - 0.03, p = 0.05) but greater trochlear rotation angles (β = 0.7, p = 0.005). Considerable mismatches in trochlear morphology were revealed between native knees and off-the-shelf TKA prostheses., Conclusions: The findings suggest that thresholds used in the diagnosis of patellofemoral instability should be adapted to patient sex and ethnicity, and that standard off-the-shelf TKA may not restore native trochlear parameters in all patients., Level of Evidence: III, retrospective comparative.

Purpose: Unexplained pain and stiffness after total knee arthroplasty (TKA) often result from mismatch between implant geometry and knee morphology, which depends on patient size, sex, and ethnicity. This study aimed to determine whether size, sex, or ethnicity are independently associated with distal femoral morphology in healthy Caucasian and Asian knees, and to compare anatomic ratios to those of commercially available TKA implants., Methods: Two series of computed tomography (CT) angiograms from France (264 knees) and China (259 knees) were used to digitize osteometric landmarks at the level of the femoral epicondyles, to measure anteroposterior (AP) and mediolateral (ML) dimensions at the anterior, posterior, medial, and lateral zones. The aspect (ML/AP), trapezoidicity (MLp/MLa), and asymmetry (APl/APm) ratios, as well as the sulcus angle were calculated and compared to those of 9 TKA models. Multivariable analyses were performed to determine whether anatomic ratios were independently associated with sex, origin, or size., Results: Multivariable analyses revealed that, independently from size, female knees were narrower (β = - 0.03; p < 0.001) and more asymmetric (β = 0.02; p < 0.001), while Chinese knees were more trapezoidal (β = 0.04; p = 0.002) and asymmetric (β = 0.02; p < 0.001) with shallower trochleae (β = 6.4°; p < 0.001). Compared to native knees, most implants were too wide, and many of the recent models too 'trapezoidal'. Most prosthetic trochleae were too shallow compared to French knees, but within the third quartile of Chinese knees., Conclusions: The morphology of the distal femur depends on sex and ethnicity independently from size. The wide spectrum of morphotypes observed cannot be covered by 'off-the-shelf' TKA models, and until customized implants become more accessible, prosthetic overhang, and under-coverage remain inevitable., Level of Evidence: III, Retrospective comparative study.

Purpose: Few studies investigated whether trochlear and patellar design enhancements improve long-term outcomes of total knee arthroplasty (TKA). This study aimed to compare the long-term survival and complication rates of two consecutive generations of the same TKA system with identical tibiofemoral geometry, but different patellofemoral designs., Methods: The authors retrieved the records of 93 patients (104 knees) operated with the HLS II system and 116 patients (122 knees) operated with HLS Evolution system. Patients were evaluated preoperatively and at a minimum of 10 years noting all complications. Kaplan-Meier (KM) survival was compared for two endpoints: (1) revision of all components and (2) revision of any component., Results: From the HLS II series, the incidence of revision of all components was 6.4%, and of any component was 9.8%. From the HLS Evolution series, the incidence of revision of all components was 4.1%, and of any component was 5.1%. Comparing the survival at equivalent follow-up of 14 years, considering revision of all components, the HLS II had higher survival than the HLS Evolution (98.9% vs 95.9%), while considering revision of any component, the HLS II had lower survival than the HLS Evolution (93.0% vs 94.9%). The differences in survival of the two implants were not significant, neither at equivalent follow-up of 14 years (n.s.), nor at maximum follow-up of each cohort (n.s.). The complication rate was higher for the HLS II series compared to the HLS Evolution (28% vs 12%, p = 0.009), but patellofemoral complications were not more frequent (8% vs 6%, n.s.)., Conclusions: Though the differences in survival of the two implants were not significant, conflicting findings are observed due to partial revisions for patellar fractures (5 in the HLS II series and 1 in the HLS Evolution series) which could be related to patellofemoral design enhancements. This study highlights the importance of patello-femoral geometry, which is often overlooked in TKA., Level of Evidence: Retrospective comparative study, Level III.

Background: Many authors recommend systematic biceps tenotomy or tenodesis when repairing rotator cuff tears, regardless of whether the biceps is normal or pathologic. The purpose of this study was to determine whether 10-year outcomes of repairs of isolated supraspinatus tears are influenced by adjuvant biceps tenodesis or tenotomy., Methods: Patients who underwent repair of isolated supraspinatus tears were recalled for evaluation at a minimum follow-up of 10 years. A total of 249 patients (51% men) aged 56.7 ± 6.3 years were evaluated clinically (Constant score), of whom 182 were also evaluated using magnetic resonance imaging (Sugaya classification). The biceps was intraoperatively found to be pathologic in 52% of shoulders, of which 39% had a tenotomy and 54% had a tenodesis; it was found to be normal in 48% of shoulders, of which 88% were left intact., Results: There were no significant differences in Constant scores for patients who had normal biceps without adjuvant procedures (77.1 ± 11.7) compared with patients who had pathologic biceps with either tenodesis (79.8 ± 11.5, P = .104) or tenotomy (75.3 ± 10.7, P = .420). However, for patients who had pathologic biceps, Constant scores were significantly better for those with tenodesis compared with those with tenotomy (P = .025). Multivariable regression revealed Constant scores to be significantly lower for women, as well as patients with fatty infiltration of stages 1 and 2, but significantly higher for patients who underwent tenodesis., Conclusion: Adjuvant biceps procedures are not required when repairing isolated supraspinatus tears, unless biceps pathology is observed intraoperatively, for which tenodesis grants better function and strength than tenotomy., (Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)