Purpose: The aim of the study was to evaluate the functional and radiological outcome following derotational distal femoral osteotomy (D‐DFO) in patients with high‐grade patellofemoral instability (PFI) and an associated increased femoral antetorsion (FA). It was hypothesized that D‐DFO would lead to a good functional and radiological outcome, and that both torsional and coronal malalignment could be normalized.Methods: Patients that underwent D‐DFO between 06/2011 and 12/2018 for high‐grade PFI with an increased FA (> 20°) were included. Patient‐reported outcome measures (Visual Analog Scale [VAS] for pain, Kujala score, Lysholm score, International Knee Documentation Committee subjective knee form [IKDC], and Tegner Activity Scale [TAS]) were evaluated pre‐ and minimum 24 months postoperatively. Magnetic resonance imaging of the lower extremity and weight‐bearing whole‐leg anteroposterior radiographs were conducted pre‐ and postoperatively. The change in FA, coronal limb alignment, and PROMs were tested for statistical significance.Results: In total, 27 patients (30 knees) were included. The D‐DFO aimed to only correct FA (Group 1) or to additionally perform a varization (Group 2) in 14 cases each. In the remaining two cases, double‐level osteotomies were performed to correct additional tibial deformities. In 25 cases (83.3%), concomitant procedures also addressing patellofemoral instability were performed. At follow‐up (38.0 months [25–75% interquartile range 31.8–52.5 months]), a significant reduction in pain (VAS for pain: 2.0 [1.0–5.0] vs. 0 [0–1.0], p < 0.05), significant improvement in knee function (Kujala Score: 55.6 ± SD 13.6 vs. 80.3 ± 16.7, p < 0.05; Lysholm Score: 58.6 ± 17.4 vs. 79.5 ± 16.6, p < 0.05; IKDC: 54.6 ± 18.7 vs. 74.1 ± 15.0, p < 0.05), and an increase in sporting activity (TAS: 3.0 [3.0–4.0] vs. 4.0 [3.0–5.0], p = n.s.) were reported. Femoral antetorsion was significantly reduced (28.2 ± 6.4° vs. 13.6 ± 5.2°, p < 0.05). A significant varization was observed in Group 2 (2.4 ± 1.2° valgus vs. 0.3 ± 2.4° valgus; p < 0.05). In one case, patellar redislocation occurred 70 months postoperatively.Conclusion: In patients with PFI and an associated increased FA, D‐DFO achieved a significant reduction in pain, an improvement of subjective knee function, as well as an adequate correction of torsional and coronal alignment.Level of evidence: Retrospective case series, Level IV.

Purpose: The aim of this study was to investigate whether malrotation of lateral knee radiographs influences posterior tibial slope (PTS) measurements.Methods: Lateral knee radiographs of all patients who underwent knee surgery at a single institution between June 2022 and January 2023 and received multiple lateral knee radiographs were included. Radiographs were categorised as malrotated lateral knee radiographs or lateral knee radiographs based on the radiographic distance between the medial and lateral posterior femoral condyles. Medial PTS (MPTS) and lateral PTS (LPTS) were evaluated on malrotated lateral knee radiographs and lateral knee radiographs and compared using the paired t test. Intra‐ and interrater reliability between four raters were assessed for MPTS and LPTS measurements.Results: A total of 92 lateral knee radiographs (46 pairs of malrotated lateral knee radiographs and lateral knee radiographs; 50.0% right side) from 46 patients (33.2 ± 12.4 years, 69.6% male) were included. Mean posterior femoral condyle distance in malrotated lateral knee radiographs was 8.1 ± 4.4 mm. Overall, MPTS and LPTS were significantly higher on malrotated lateral knee radiographs versus lateral knee radiographs (medial: 10.5 ± 3.2° vs. 9.7 ± 3.5°, p < 0.05; lateral: 10.6 ± 3.4° vs. 9.7 ± 3.3°, p < 0.05). Mean absolute difference between MPTS and LPTS on malrotated lateral knee radiographs versus lateral knee radiographs were |1.9| ± |1.5|° and |2.0| ± |1.8|°, respectively. Intrarater reliability was ‘moderate’ and interrater reliability was ‘good’ for both MPTS and LPTS.Conclusion: Malrotation of lateral knee radiographs led to a significant distortion of both the MPTS and LPTS. In clinical practice, attention should be placed on the (mal)rotation of lateral knee radiographs, especially in patients for whom a slope‐correcting osteotomy is being discussed.Level of Evidence: Level IV.

Background: Biomechanical studies have shown that an increased medial posterior tibial slope (MPTS) may affect anteroposterior knee laxity and tibial shear forces, ultimately increasing the risk for graft failure after anterior cruciate ligament (ACL) reconstruction. Previous clinical studies have, however, reported inconclusive results. Purpose: The purpose of this study was to evaluate the relationship between the MPTS and graft failure as well as functional outcomes after anatomic primary isolated ACL reconstruction using a hamstring tendon autograft. It was hypothesized that an increased MPTS would be associated with a higher ACL graft failure rate. Furthermore, a higher MPTS would negatively correlate with functional outcomes in patients without ACL graft failure. Study Design: Case-control study; Level of evidence, 3. Methods: Consecutive patients who underwent isolated primary ACL reconstruction with an anteromedial portal drilling technique between January 2011 and December 2019 were retrospectively reviewed. The MPTS was measured on preoperative lateral knee radiographs. At a minimum of 24 months postoperatively, the ACL graft failure rate and patient-reported outcome measures (PROM; International Knee Documentation Committee subjective knee form, Lysholm score, Tegner Activity Scale, visual analog scale for pain and subjective instability) were evaluated. Differences in the MPTS between patients with and without ACL graft failure as well as the frequency of graft failure between those with an MPTS <12° and those with an MPTS ≥12° were assessed for statistical significance. Binary logistic regression analysis was performed to stratify the risk of graft failure with the following variables: MPTS, age at surgery, and sex. Correlation analysis was performed to evaluate the relationship between the MPTS and PROM in patients without ACL graft failure. Results: In total, 326 patients were included (median follow-up, 71.0 months [IQR, 49.0-104.0 months]). There was no significant difference in the MPTS between patients with and without graft failure (10.6°± 3.2° vs 11.2°± 2.8°, respectively; P = .264). Additionally, there was no significant difference in the frequency of graft failure between patients with an MPTS <12° and those with an MPTS ≥12° (15.6% vs 16.5%, respectively; P = .835). Binary logistic regression showed that younger age at the time of surgery (odds ratio, 1.069 [95% CI, 1.031-1.109]) was associated with graft failure; sex and MPTS were not associated with graft failure. In patients without ACL graft failure, there was no significant correlation between the MPTS and PROM. Conclusion: In patients who underwent anatomic primary isolated ACL reconstruction, an increased MPTS was not associated with a higher rate of graft failure or inferior functional outcomes. Younger age was a significant nonmodifiable risk factor for ACL graft failure.

Background: Posterior medial meniscus root tears are commonly treated with a transtibial pull-out (TO) repair, but significant postoperative meniscal extrusion has been reported. Recently, knotless adjustable suture anchor fixation has been introduced to treat root tears. This anchor-based fixation demonstrates less cyclic displacement than a TO repair. However, it is unknown how meniscal extrusion and contact mechanics compare between these 2 repair techniques when the meniscus endures cyclic tibiofemoral loading. Hypothesis: Suture anchor repair will demonstrate reduced meniscal extrusion and lower medial compartment pressure at the 1000th cycle compared with the TO repair. Study Design: Controlled laboratory study. Methods: Eight pairs of cadaveric knees were used to compare extrusion and contact pressure between transtibial fixation and suture anchor repair techniques for medial meniscus posterior root tears. Each specimen underwent cyclic compressive loading (0th, 100th, 500th, and 1000th cycles). Medial meniscal extrusion was assessed with the knee at full extension using ultrasound, and medial compartment contact pressures were evaluated using pressure sensors. Statistical analyses included paired t tests and repeated-measures analysis of variance with an alpha level set at .05. Results: The suture anchor repair technique demonstrated significantly lower absolute and relative medial meniscal extrusion compared with transtibial fixation repair after 500 and 1000 cycles of loading ( P = .012 and P = .001, respectively). Similarly, mean medial compartment pressures were significantly lower in the suture anchor repair group compared with the transtibial fixation repair group after 1000 cycles ( P = .028). No significant differences were found in peak pressures between the 2 repair techniques. Conclusion: The suture anchor repair demonstrated lower medial meniscal extrusion and reduced medial compartment contact pressures after time-zero cyclic loading. This biomechanical profile may be important for increasing the likelihood of healing and may translate to improved long-term outcomes for patients undergoing meniscus root repair. Clinical Relevance: Understanding the biomechanical differences between repair techniques at time zero may be crucial for optimizing surgical outcomes and minimizing the risk of long-term joint degeneration after meniscus root tears. Future clinical studies should further investigate these findings in live patient populations to validate their effect on root healing, functional outcomes, and long-term osteoarthritis progression.

Purpose: The purpose of this study was to investigate the impact of sex on knee function, activity and quality of life following meniscus surgery using data from the German Arthroscopy Registry.Methods: This is a retrospective cohort study with data collected between 2017 and 2022. Patient‐reported outcome measures (PROMs), namely Knee Injury and Osteoarthritis Outcome Score (KOOS), EuroQol Visual Analogue Scale (EQ Scale), and Marx Activity Rating Scale (MARS), were collected preoperatively and at 6, 12 and 24 months postoperatively. Data were analysed to examine differences between male and female patients regarding PROMs, pre‐existing conditions, meniscus lesion types and surgical treatments.Results: A total of 1106 female (36.6%) and 1945 male patients (63.7%) were included. Males were significantly younger than females and had a higher body mass index. Overall, there were four times more medial meniscus lesions (MMLs) (77.5%) than lateral meniscus lesions (LMLs) (27.9%). Degenerative LMLs were more frequent in females, while traumatic LMLs were more common in males. Frequencies of traumatic and degenerative MMLs were similar among males and females. Males had higher absolute KOOS irrespective of treatment or meniscus lesion type. Meniscus repair resulted in similar improvements in ΔKOOS for both sexes, while meniscus resection exhibited higher absolute KOOS for males at each time point. Males generally had higher EQ Scale and MARS than females.Conclusion: Greater improvements in knee function, activity and quality of life were observed in males. While MMLs appear to be comparable among sexes, the nature of LML differed significantly. These results may help surgeons to refine patient selection for specific treatments to improve overall clinical outcomes.Level of Evidence: Level III.