Objective Cartilage defect is a common pathology still lacking a unified treating option. The purpose of this retrospective study is to evaluate the safety, efficacy, and clinical and radiological outcome of cartilage restoration of knee joint with allogenic next‐generation Matrix‐Induced Autologous Chondrocyte Implantation (MACI) for the first time, as well as the correlation between postoperative clinical and radiological outcomes and preoperative patient history and demographics. Methods From July 2014 to August 2020, 15 patients who went through cartilage restoration with allogenic next‐generation MACI were included in this study. Patient demographics and PROM including the International Knee Documentation Committee (IKDC) subjective knee score, Lysholm score, Tegner Activity Scale (TAS), and Knee Injury and Osteoarthritis Outcome Score (KOOS) were obtained preoperatively, at 3, 6, 12 months postoperatively and the last follow‐up using an online questionnaire platform. MOCART 2.0 score was calculated at the last follow‐up. Analysis of variance (ANOVA) was used to compare PROM pre‐ and post‐operation, with two‐tailed p < 0.05 defined as statistical significant. Pearson correlation coefficient was used to evaluate correlation between the PROM and MOCART 2.0 score at the last follow‐up with patients demorgraphics. Results All patients were followed for an average of 66.47 ± 24.15 months (range, 21–93). All patients were satisfied with the outcome of the surgery and no complication was reported at the end of the study. No significant improvement was observed until 1 year after the implantation, except for IKDC score at 6 months. All PROM showed significant improvement 1 year post‐op except for Lysholm score and TAS, which also increased significantly at the time of the last follow‐up. Pearson correlation coefficient showed that the size of the defect, before or after debridement, was significantly negatively correlated with final KOOS‐Pain (before debridement: r = −0.57, p < 0.05; after debridement: r = −0.54, p < 0.05) and KOOS‐Symptoms score (before debridement: r = −0.66, p < 0.05; after debridement: r = −0.67, p < 0.05). The MOCART 2.0 score was found significantly and negatively correlated with BMI (r = −0.60, p < 0.05), and significantly and positively correlated with Lysholm score (r = 0.70, p < 0.05). Conclusion The next generation MACI with autologous chondrocyte and allogenic chondrocyte ECM scaffold could be used to treat focal articular cartilage defect in the knee joint safely and efficiently with lasting promising outcomes for more than 5 years. The size of the defects should be considered the most negatively correlated parameters influencing the postoperative clinical outcomes.

Purpose ：This retrospective study summarized the clinical, radiographic and arthroscopic manifestation of synovial chondromatosis (SC) of the hip, along with the post-operative effect to discuss the curative effect of arthroscopic management of hip SC. Methods : 21 patients underwent arthroscopic surgery from the same surgeon for hip SC were followed up for an average of 45 months. T-shaped capsulotomy was routinely performed in each case. Visual analog scale, range of motion, modified Harris Hip score and International Hip Outcome Tool score were collected preoperatively and at the time of the latest follow-up. All patients’ demographics, radiographs and arthroscopic images were collected to summarize and conclude the similarities and differences of their manifestation. Results : Large wedged clumps of loose bodies demonstrated distinguishable radiographic, arthroscopic appearance and demanded different surgical strategy. Postoperative scores were all significantly improved. One case of residual pain and two cases of residual loose bodies with no symptom related were reported at the final follow up. All but one patients were satisfied with the outcome. Conclusion : Arthroscopy treatment of hip SC with T-shaped capsulotomy has demonstrated good result in terms of clinical outcome score, recurrence rate and complication rate. On the basis of this study, we concluded the clinical performance of large wedged clumps of loose bodies of hip SC.