膝关节单髁置换术治疗晚期膝关节自发性骨坏死

 目的 探讨膝关节单髁置换术治疗晚期膝关节自发性骨坏死的手术技术与疗效。方法 回顾性分析2009年1月至2013年6月收治的27例（27膝）采用膝关节单髁置换术治疗的晚期膝关节自发性骨坏死患者的病例资料。男12例，女15例；年龄52~82岁，平均（64.6±8.6）岁。体重指数18.0~30.2 kg/m²，平均（24.2±2.9） kg/m²。左侧13例，右侧14例。均发生在内侧间室，位于股骨远端内侧髁25例，胫骨内侧平台2例。Mont膝关节骨坏死分期Ⅲ期11例，Ⅳ期16例。采用Biomet公司第3代Oxford单髁假体行膝关节单髁置换术。术后3、6、12个月及以后每年随访1次。对患者满意率、膝关节疼痛视觉模拟评分（visual analogue scale，VAS）、关节活动度、HSS膝关节评分进行评估。结果 全部病例随访6~59个月，平均27.8个月。随访期间无感染、假体脱位、假体松动、下肢静脉血栓形成、肺栓塞、心脑血管意外、创伤后精神障碍等并发症发生。1例于术后3年发生车祸致胫骨平台外侧骨折及股骨内侧髁撕脱骨折而行翻修术。1例出现股骨假体旋转超过10°，1例出现胫骨下透光线。末次随访时患者满意率为96.3%（26/27）；疼痛VAS评分由术前（6.9±0.9）分降至（2.0±1.1）分；HSS膝关节评分由术前（61.3±9.7）分增至（93.0±4.8）分，优良率96.3%（26/27）；膝关节活动度为125.7°±9.6°；股胫角为177.7°±3.1°。结论 膝关节单髁置换术治疗晚期膝关节自发性骨坏死近期疗效满意，具有创伤小、症状改善明显、术后关节功能良好的特点。

Minimally invasive unicompartmental knee arthroplasty for spontaneous osteonecrosis of the knee joint

Objective To explore the outcome and surgical technique of minimally invasive unicompartmental knee arthroplasty (UKA) for spontaneous osteonecrosis of the knee joint. Methods From January 2009 to June 2013, twenty-seven cases with medial compartmental spontaneous osteonecrosis treated by minimally invasive Oxford phase 3 UKA were reviewed retrospectively. Twelve knees were male and 15 were female, with an average age of 64.6±8.6 years (52-82 years). At the time of diagnosis, 11 patients presented with grade Ⅲ necrosis, and 16 grade Ⅳ, following Mont's classification. The pain, range of motion (ROM) and HSS score of the knees were evaluated before and after UKA. Pre- and post-operative alignment of the low limbs were measured and compared respectively. According to the guidelines proposed by the Oxford group, postoperative radiographic assessments were made at the final follow-up. Results All of the patients were followed up for a mean time of 27.8±15.9 months (6-59 months). There were no serious adverse events such as infection, bearing dislocation, aseptic loosening, pulmonary embolism, deep venous thrombosis, cardio-cerebral vascular incident or psychogenia. There was 1 revision from unrelated causes (fracture of tibia plateau) at 3 years after arthroplasty. One femoral component was tilted with postoperative radiographic angle＞10°. One radiolucent line was observed in the SONK series. There were no clinical symptoms of the two implant failures at the last follow up. VAS score was reduced from 6.9±0.9 to 2.0±1.1 (t=19.27, P=0.00）. 96.3% (26/27) of pain was relieved. The mean post-operative ROM and femorotibial angle were 125.7°±9.6°, 177.7°±3.1°, respectively. HSS score was increased from 61.3±9.7 to 93.0±4.8 (t=14.46, P=0.00). Of the patients, 96.3% (26/27) were satisfied with the outcome of this surgical procedure. Conclusion Minimally invasive UKA is an effective method for spontaneous osteonecrosis of the knee with fewer traumas and fast recovery. The early term outcome of UKA is encouraging.