Department of Diagnostic and Interventional Radiology, Faculty of Medicine, University Medical Center Freiburg, University of Freiburg, Freiburg, Germany.
Department of Radiology, Klinikum Rechts der Isar, School of Medicine, Technical University of Munich, Munich, Germany.
Am J Sports Med. 2021 Feb;49(2):476-486. doi: 10.1177/0363546520980134. Epub 2021 Jan 11.
Matrix-associated autologous chondrocyte implantation (MACI) with autologous bone grafting (ABG) is an effective surgical treatment for osteochondral defects. Quantitative magnetic resonance imaging (MRI) techniques are increasingly applied as noninvasive biomarkers to assess the biochemical composition of cartilage repair tissue.
To evaluate the association of quantitative MRI parameters of cartilage repair tissue and subchondral bone marrow with magnetic resonance morphologic and clinical outcomes after MACI with ABG of the knee.
Case series; Level of evidence, 4.
Qualitative and quantitative 3 T MRI of the knee was performed in 21 patients (16 male) at 2.5 years after MACI with ABG at the medial (18/21) or lateral (3/21) femoral condyle for the treatment of osteochondral defects. Morphologic MRI sequences were assessed using MOCART (magnetic resonance observation of cartilage repair tissue) 2.0 scores. T2 relaxation time measurements for the assessment of cartilage repair tissue (CRT2) were obtained. Single-voxel magnetic resonance spectroscopy was performed in underlying subchondral bone marrow (BM) and at both central femoral condyles. The presence of pain and Tegner scores were noted. Statistical analyses included Student tests, correlation analyses, and multivariate regression models.
The mean defect size was 4.9 ± 1.9 cm. At a follow-up of 2.5 ± 0.3 years, 9 of 21 patients were asymptomatic. Perfect defect filling was achieved in 66.7% (14/21) of patients. MOCART 2.0 scores (74.1 ± 18.4) did not indicate pain (68.3 ± 19.0 [pain] vs 81.7 ± 15.4 [no pain]; = .102). However, knee pain was present in 85.7% (6/7) of patients with deep bony defects (odds ratio, 8.0; = .078). Relative CRT2 was higher in hypertrophic cartilage repair tissue than in repair tissue with normal filling (1.54 ± 0.42 vs 1.13 ± 0.21, respectively; = .022). The underlying BM edema-like lesion (BMEL) volume was larger in patients with underfilling compared with patients with perfect defect filling (1.87 ± 1.32 vs 0.31 ± 0.51 cm, respectively; = .002). Patients with severe pain showed a higher BMEL volume (1.2 ± 1.3 vs 0.2 ± 0.4 cm, respectively; = .046) and had a higher BM water fraction (26.0% ± 12.3% vs 8.6% ± 8.1%, respectively; = .026) than did patients without pain.
Qualitative and quantitative MRI parameters including the presence of subchondral defects, CRT2, BMEL volume, and BM water fraction were correlated with cartilage repair tissue quality and clinical symptoms. Therefore, the integrity of subchondral bone was associated with outcomes after osteochondral transplantation.
基质相关的自体软骨细胞植入（MACI）联合自体骨移植（ABG）是治疗骨软骨缺损的有效手术方法。定量磁共振成像（MRI）技术作为一种非侵入性生物标志物，越来越多地被用于评估软骨修复组织的生化成分。
评估膝关节 MACI 联合 ABG 后软骨修复组织和软骨下骨髓的定量 MRI 参数与磁共振形态学和临床结果之间的相关性。
病例系列；证据水平，4 级。
21 例患者（16 例男性）在接受 MACI 联合 ABG 治疗骨软骨缺损后 2.5 年进行膝关节 3T MRI 检查，其中 18 例在股骨内侧髁，3 例在股骨外侧髁。使用 MOCART（磁共振软骨修复组织观察）2.0 评分评估形态学 MRI 序列。获取软骨修复组织的 T2 弛豫时间测量值（CRT2）。在软骨下骨髓（BM）和双侧股骨髁中央进行单体素磁共振波谱分析。记录疼痛和 Tegner 评分。统计分析包括学生 t 检验、相关分析和多元回归模型。
平均缺损大小为 4.9 ± 1.9 cm。在 2.5 ± 0.3 年的随访中，21 例患者中有 9 例无症状。66.7%（14/21）的患者达到了完美的缺损填充。MOCART 2.0 评分（74.1 ± 18.4）与疼痛无关（68.3 ± 19.0 [疼痛]与 81.7 ± 15.4 [无疼痛]； =.102）。然而，在 85.7%（6/7）的深部骨缺损患者中存在膝关节疼痛（优势比，8.0； =.078）。与正常填充的修复组织相比，肥大性软骨修复组织的相对 CRT2 更高（1.54 ± 0.42 比 1.13 ± 0.21； =.022）。与完美填充的缺损相比，软骨下骨髓水肿样病变（BMEL）体积在填充不足的患者中更大（1.87 ± 1.32 比 0.31 ± 0.51 cm； =.002）。严重疼痛的患者具有更高的 BMEL 体积（1.2 ± 1.3 比 0.2 ± 0.4 cm； =.046）和更高的 BM 水分数（26.0% ± 12.3%比 8.6% ± 8.1%； =.026）。
包括软骨下缺损、CRT2、BMEL 体积和 BM 水分数在内的定性和定量 MRI 参数与软骨修复组织质量和临床症状相关。因此，软骨下骨的完整性与骨软骨移植后的结果相关。
