膝软骨活检后约30%的患者在平均4.3年随访时接受基质诱导的自体软骨细胞植入术（MACI）
简介
该单中心研究纳入202例接受MACI软骨活检的膝关节软骨缺损患者，平均随访4.3年，仅约31%最终行二期MACI植入，中位间隔9.4个月。较低的BMI与更高植入率相关，缺损面积>4cm²者植入更早；未植入者中约60%因活检时同期软骨成形术而症状改善。提示术前需筛选患者，活检可兼顾治疗作用。
英文摘要
PURPOSE: To evaluate implantation rates, time to implantation, and predictors of implantation following matrix-induced autologous chondrocyte implantation (MACI) biopsy for knee chondral defects. METHODS: Patients undergoing MACI biopsy or implantation for symptomatic knee chondral defects from 2017 to 2024 at a single institution were reviewed. At a minimum 1-year follow-up, the decision to proceed with implantation, recurrent symptoms, complications, and reoperations were assessed. Kaplan-Meier analysis estimated time to implantation, and multivariable logistic regression identified predictors of MACI implantation. RESULTS: A total of 208 knees in 202 patients (mean age 28.0 ± 10.9 years, range 11-59) underwent MACI biopsy for 243 chondral defects (patella [38%], femoral condyle [34%], and trochlea [26%]). At a mean follow-up of 4.3 years (range 1.0-8.3), 64 knees (31%) proceeded to second-stage MACI implantation. Among 144 knees not implanted, 87 (60%) reported symptom improvement, and 26 (18%) had persistent symptoms. The remaining 22% did not undergo implantation due to another cartilage procedure, insurance denial, or pending scheduling. Patients who underwent biopsy at the home institution had a shorter time from biopsy to implantation compared with those biopsied at outside institutions (6.1 vs 13.1 months, P = .001). Median time to implantation was 9.4 months (95% confidence level: 7.2-12.2) for home biopsies. Lower body mass index was associated with progression to implantation after adjusting for covariates (odds ratios 0.92, P = .019). Patients implanted within 4 months had larger chondral defects (4.0 vs 3.0 cm2, P = .045). At a mean 4.1-year follow-up, 6 patients (8%) experienced postoperative complications, including 3 (4%) who required revision chondroplasty. CONCLUSIONS: MACI biopsy for knee chondral defects resulted in approximately one-third of patients proceeding to MACI implantation, at a median of 9.4 months after biopsy. Lower body mass index was associated with higher likelihood of progression to implantation, larger chondral defects with earlier implantation, and among patients who did not proceed to implantation, approximately 60% reported symptom improvement following concomitant chondroplasty at the time of biopsy. LEVEL OF EVIDENCE: Level IV, retrospective case series.