PurposeTo develop a simple and effective method for evaluating the femoral tunnel position using the apex of the deep cartilage (ADC) as the landmark. MethodsA total of 52 patients who underwent arthroscopic ACL reconstruction were recruited between June and September 2021. The femoral tunnel was placed on the central point of the anteromedial footprint with an accessory anteromedial and a high anterolateral portal. Then, the length from the ADC to the shallow cartilage margin (L1) and to the center of the femoral tunnel (l1), as well as the center to the low cartilage margin (H1, intraoperative height), was measured under arthroscopy and on postoperative CT scans (L2, l2 and H2). Moreover, intraoperative and postoperative cartilage ratios were equivalent to l1/L1 and l2/L2, respectively. Linear regression, Pearson correlation and Bland–Altman analysis were performed to evaluate the consistency between these two measurements of cartilage ratio (l/L) and height (H). ResultsThe mean age at the time of surgery was 28.7 years; 42 patients were male, and 17 patients were hurt in the left knee among 52 patients. The intraoperative cartilage ratio was 0.37 ± 0.04, and the height was 8.1 ± 1.1 mm with almost perfect inter‐observer reproducibility. After the surgery, the cartilage ratio and height were measured as 0.39 ± 0.04 and 8.2 ± 1.3 mm on 3D–CT, respectively, with almost perfect intra‐ and inter‐observer reproducibility. Significant positive correlations and linear regression were detected in the cartilage ratio (r = 0.844,p < 0.001), and height (r = 0.926,p < 0.001) intraoperatively and postoperatively. The Bland–Altman plot also showed excellent consistency between arthroscopy and 3D–CT. ConclusionsThe ADC is a good landmark in the assessment of femoral tunnel position, with excellent consistency between intraoperative arthroscopic measurements and postoperative 3D–CT.ClinicalTrials.gov Identifier: NCT04937517. Level of Evidence Level III.

ObjectivesThe aims of the study are to describe the injury patterns among recreational skiers and snowboarders in China and to provide primary data to guide the reconstruction of regional healthcare facilities to deal with the increasing number of participants in snow sports.DesignRetrospective cross-sectional study.MethodsA retrospective study was performed in Wanlong Ski Resort in Chongli, China. Data of all injured skiers and snowboarders treated in the resort clinic during the 2018–2019 season were collected. Patients’ information, including sex, age, equipment, skill level and injured body part, was analysed.ResultsA total of 753 sports injuries were recorded. The estimated incidence of injury was 1.98 per 1000 skier days. 453 cases (60.2%) were associated with skiing. The mean age of skiers was older than snowboarders (35.1±14.5 vs 29.0±8.9, p<0.01). Injury not involving others constituted 67.9% of all injuries. The most common injured body part among skiers was lower extremity, contrary to injury in the upper extremity among snowboarders. Head and cervical injury was identified in 13.7% of skiers and 13.6% of snowboarders.ConclusionThe incidence of skiing/snowboarding injury in China was similar to other countries. Injury pattern differed among different sports and causes of injury.

Background To evaluate the anatomic geometry of the posterior intercondylar eminence and its association with PCL injury risk. Methods Patients who underwent primary PCL reconstruction from 2015 to 2018 were retrospectively analyzed. The control group included inpatients diagnosed with ACL rupture because of a sports-related accident during the same period, matched by age, gender, height, weight, and side of injury. Measurements of the height of the apex of the posterior intercondylar eminence (HPIE), the slope length (SLPIE) and the slope angle (SAPIE) of the posterior intercondylar eminence were performed using conventional MRI scans assessed by 2 blinded, independent raters. Intraclass correlation coefficients (ICCs) was used to evaluate the consistency of measurement results. Independent sample t tests, Chi-square tests, and logistic analyses were used to compare the two group, with P < 0.05 considered statistically significant. Results Fifty-five patients with PCL rupture met the inclusion criteria and 55 PCL-intact matched controls were included. There were no significant differences between the groups in gender (P = 1.000), limb side (P = 0.848), age (P = 0.291), BMI (P = 0.444) or height (P = 0.290). Inter-observer reproducibility was excellent agreement in HPIE, SLPIE and SAPIE of case and control groups (ICC: HPIE = 0.81, SLPIE = 0.77, SAPIE = 0.85). Patients with PCL rupture had significantly greater HPIE, SAPIE (both P < 0.001), and SLPIE (P < 0.05) than PCL-intact patients. The multivariable analysis showed that HPIE (OR, 1.62 [95% CI, 1.24–2.11], P < 0.001) and SAPIE (OR, 1.17 [95% CI, 1.05–1.31], P < 0.001) were independent factors associated with PCL rupture. Conclusion Through this retrospective observational study, we found that patients with PCL rupture may have a higher posterior intercondylar eminence compared to PCL-intact patients. Level of evidence III.

No abstract