重度膝关节外翻畸形的全膝关节置换术

 目的 探讨重度膝关节外翻畸形全膝关节置换术的手术方法及临床效果。方法 对2007年1月至2012年12月采用全膝关节置换治疗的重度膝关节外翻畸形患者22例（23膝）进行回顾性分析。男7例，女15例；年龄41~78岁，平均65岁。股胫角（股骨和胫骨解剖轴线的夹角）22°~50°，平均为34.6°。骨关节炎17例，类风湿关节炎5例。髌骨完全脱位3例3膝，内侧不稳定1例1膝，屈曲挛缩畸形3例4膝。21例22膝采用后稳定型假体，1例1膝采用限制型假体。髌旁内侧入路、常规截骨及单纯外侧软组织松解，术中行髌骨置换5例。以膝关节活动度、X线股胫角及美国特种外科医院（Hospital for Special Surgery，HSS）膝关节评分评价术后疗效。结果 全部病例随访时间1~5年，平均2.5年。膝关节活动度由术前平均43.7°±5.8°（0°~80°）提高至末次随访时110.6°±7.5°（80°~130°），HSS膝关节评分由术前平均（19.6±4.7）分（6~34分）提高至末次随访时（89.7±3.6）分（84~96分），手术前后的差异有统计学意义。外翻畸形基本得到矫正，末次随访时股胫角平均为8.6°±0.8°（0°~12°），较术前34.6°±2.4°（22°~50°）明显改善，手术前后的差异有统计学意义。术后2例2膝有膝关节内侧不稳症状，给予膝关节支具保护；1例1膝术前严重髌骨脱位患者术后存在半脱位，未予特殊处理；2例2膝术后出现腓总神经麻痹，未予特殊处理。随访期间未发生感染、松动及深静脉血栓形成等并发症。结论 对重度膝关节外翻畸形患者可采用常规截骨、单纯外侧软组织松解及后稳定型假体植入，能较好地矫正外翻畸形，近期疗效满意。

Total knee arthroplasty for severe valgus knee deformity

Objective To investigate the surgical methods and clinical effects of total knee arthroplasty (TKA) in patients with severe valgus knee deformity. Methods From January 2007 to December 2012, 22 patients with 23 severe valgus knee deformity underwent TKA by means of medial parapatellar approach, standard osteotomy and only lateral soft tissue release with posterior stabilized implants were retrospectively analyzed. They were 7 males and 15 females, aged from 41 to 78 years, with an average age of 65 years. Tibiofemoral angle (angle between the femur and tibia anatomic axis) was 22°-50°, with an average of 34.6±2.4°. Among them, 17 cases were osteoarthritis, 5 cases were rheumatoid arthritis, 3 cases complicated with patella dislocations, 1 case complicated with medial instability, 3 cases of 4 knees complicated with flexion contracture. Posterior stabilized prosthesis were used in 21 cases of 22 knees, constrained prosthesis were used in 1 case of 1 knee, 5 cases accepted intraoperative patellar replacement. Clinical and radiographic evaluations including range of motion (ROM), the Hospital for Special Surgery (HSS) knee score and the tibial and femur angle (T-F angle) were performed at follow-up. Results The duration of follow-up averaged 30.5 months. The average HSS score improved from 19.6±4.7 points preoperatively to 89.7±3.6 points at the time of the last follow-up. The average ROM improved from 43.7±5.8° preoperatively to 110.6±7.5°. The average T-F angle was 8.6±0.8°. We had 5 patella replacements, 2 medial instability cured by using articular branches, 2 palsies of nervus peroneus communis recovering after 3 months. No complications such as infection, DVT, or component loosening. Conclusion The techniques of medial parapatellar approach, standard osteotomy and only lateral soft tissue release with posterior stabilized implants can deal with a severe valgus knee deformity very successfully in patients undergoing primary total knee arthroplasty, and provide excellent results.