外侧髌旁入路膝关节置换术治疗膝外翻合并膝骨关节炎的疗效分析

Total knee arthrolpasty by lateral parapatellar approach for valgus knee with osteoarthritis

目的探讨外侧髌旁入路膝关节置换治疗膝外翻合并膝骨关节炎（OA）的临床效果。方法对2008年1月至2012年12月,在广州军区广州总医院接受外侧髌旁入路膝关节置换术治疗膝外翻合并膝OA的17例患者进行回顾性分析。其中男4例,女13例;年龄60~76岁。16例采用后稳定型假体,1例1膝采用限制型假体。通过髌旁外侧入路Z字形错层切开关节囊、松解髂胫束、外侧副韧带及后外侧关节囊进行软组织平衡,股骨远端外翻5°截骨,采用Whiteside线和内外上髁轴线定位,确定股骨前后髁截骨外旋角度,术后屈曲缝合关节囊。以膝关节活动度、股胫关节外翻角及美国特种外科医院（HSS）评分评价术后疗效。采用配对t检验对上述计量资料进行统计分析。结果1例患者术中内翻髌骨时出现髌韧带止点部分撕脱,采用锚线钉予以重建。全部病例随访2~6年;随访期间未发生感染、松动、膝关节不稳定及外翻等并发症。术后股胫关节外翻角为（6.6±1.3）°,小于术前的（26.5±4.6）°,且差异有统计学意义（t=17.00,P〈0.05）;术后末次随访膝关节HSS评分为（85.4±2.9）分,大于术前的（35.5±9.9）分,,且差异有统计学意义（t=19.99,P〈0.05）;术后末次随访膝关节活动度为（106.0±8.9）°,大于术前的（81.6±16.1）°,且差异有统计学意义（t=5.47,P〈0.05）。结论通过精确的截骨及软组织平衡技术,外侧髌旁入路膝关节置换治疗膝外翻合并膝OA可以取得满意的临床疗效。

Objective To investigate the clinical effects of total knee arthroplasty（ TKA） by lateral parapatellar approach in the patients with valgus knees and osteoarthritis（ OA）. Methods From January 2008 to December 2012,17 patients with valgus knees and osteoarthritis were analysed,who underwent TKA by lateral parapatellar approach in Guangzhou general hospital of Guangzhou military command,including four males and 13 females,aged from 60 to 76 years,65 years in average. Posterior stabilized prostheses were used in 16 knees. Constrained prosthesis was used in one knee. After the incision of the skin,the joint capsule was cut open laterally from the parapatellar edge with Z-shape. Soft tissue balance was performed by releasing the iliotibial band,the lateral collateral ligament and posterolateral joint capsule. The valgus angle of distal femur osteotomy was five degrees. Whiteside line and epicondylar line connected internal and lateral condyle were used to determine the external rotation angle of femur osteotomy. The capsule was closed with the knee was flexed. Clinical and radiographic evaluations including range of motion（ ROM）,the hospital for special surgery（ HSS） knee score and femoral tibial joint ectropion angle were evaluated during the follow-up. The paired samples t-test was used to analyse the difference between the measurement data. Results One case of patellar ligament injury occured when the patella was turned inward which was reconstructed with anchors. The duration of the follow-up was from two to six years,3. 8 years years in average. No complication such as infection,loosening,knee instability,valgus or other complication was observed. The femoral tibial joint ectropion angle was（ 6. 6 ± 1. 3） ° after the operation,which reduced significantly compared with the angle（ 26. 5 ± 4. 65） ° before the operation（ t = 17. 00,P〈0. 05）. The HSS score was（ 85. 4 ± 2. 9） at the last follow-up,which was higher than the score（ 35. 5 ± 9. 9） before the operation（ t = 19. 99,P〈0. 05）. The ROM was（ 106 ± 8. 9） ° after the operation,which was better than the one（ 81. 6 ± 16. 1） ° before the operation（ t = 5. 47,P〈0. 05）.Conclusion Through accurate osteotomy and soft tissue balancing techniques,TKA by lateral parapatellar approach for valgus knee with osteoarthritis can achieve excellent results.