Higuchi Hiroshi, Kobayashi Yasukazu, Kobayashi Atsushi, Hatayama Kazuhisa, Kimura Masashi
Department of Orthopaedic Surgery, Asakura Sports Rehabilitation Clinic, Maebashi, Gunma, Japan.
Am J Orthop (Belle Mead NJ). 2013 May;42(5):220-2.
Bone marrow signal changes on magnetic resonance imaging (MRI) after meniscectomy have been reported as evidence of postmeniscectomy osteonecrosis, but this pathology is unclear. We conducted a study to follow-up cases with bone marrow signal changes on MRI after meniscectomy and investigate the pathology of underlying lesions. Of 136 patients with no presurgical evidence of osteonecrosis, 29 had juxta-articular bone marrow signal changes on MRI after arthroscopic meniscectomy and subsequently underwent conservative therapy. In 6 of these 29 patients, clinical symptoms and radiographic changes began deteriorating. Based on the Koshino classification, 4 of the 6 patients had Stage-2 knee osteonecrosis and 2 had Stage-3. Arthroscopic and pathologic examinations were performed. Arthroscopic findings were fibrillation (all 6 cases), fissuring (4), ulceration (2), and eburnation (2). Histologic analysis confirmed subchondral bone fractures in all 6 cases, but osteonecrotic lesions were detected only in 2 cases with obvious radiologic deterioration. Postmeniscectomy osteonecrosis might result from subchondral bone fractures. Fracture healing is worse in patients with comorbidities than in those without it; comorbidities might be a risk factor for osteonecrosis.
半月板切除术后磁共振成像（MRI）上的骨髓信号变化已被报道为半月板切除术后骨坏死的证据，但这种病理情况尚不清楚。我们开展了一项研究，对半月板切除术后MRI上有骨髓信号变化的病例进行随访，并调查潜在病变的病理情况。在136例术前无骨坏死证据的患者中，29例在关节镜下半月板切除术后MRI上出现关节周围骨髓信号变化，随后接受了保守治疗。在这29例患者中，有6例患者的临床症状和影像学改变开始恶化。根据小筱分类法，这6例患者中有4例为2期膝关节骨坏死，2例为3期。进行了关节镜检查和病理检查。关节镜检查结果为纤维化（6例均有）、裂隙形成（4例）、溃疡形成（2例）和骨质象牙样变（2例）。组织学分析证实所有6例均有软骨下骨骨折，但仅在2例影像学明显恶化的病例中检测到骨坏死病变。半月板切除术后骨坏死可能由软骨下骨骨折引起。合并症患者的骨折愈合情况比无合并症患者更差；合并症可能是骨坏死的一个危险因素。
