Vaidya Shrinand V, Patel Mihir R, Panghate Atul N, Rathod Parthiv A
Department of Orthopedic Surgery, King Edward VII Memorial Hospital and Seth Gordhandas Sundardas Medical College, Mumbai, India.
Indian J Orthop. 2010 Jul;44(3):300-7. doi: 10.4103/0019-5413.65159.
Limb length discrepancy and its effects on patient function have been discussed in depth in the literature with respect to hip arthroplasty but there are few studies that have examined the effect on function of limb length discrepency following total knee arthroplasty (TKA). The aim of this study was to determine whether limb length discrepancy after TKA in patients with bilateral osteoarthritis of knee with varus deformity affects functional outcome.
Fifty-four patients with bilateral osteoarthritis of knee with varus deformity, who were operated for total knee arthroplasty from 1996 to 2008, were reviewed retrospectively. The patients were divided into two groups. Thirty patients (mean age 64 years) were operated for unilateral TKA and thirty patients (mean age 65.8 years) were operated for bilateral total knee arthroplasty. Six patients underwent staged surgery and were included in both groups as the time interval between the two surgeries was more than the minimum 6-month follow-up period specified for inclusion in the study. The limb length discrepancy was measured and statistically correlated with the functional component of the Knee Society Score.
In the unilateral group (n=30), the mean limb length discrepancy was 1.53 cm (range: 0-3 cm) and the mean functional score was 73 (range: 45-100). In the bilateral group (n=30), the mean limb length discrepancy was 0.5 cm (range: 0-2 cm) and the mean functional score was 80.67 (range: 0-100). A statistically significant negative correlation was found between limb length discrepancy and functional score in the unilateral group (Spearman correlation coefficient, r =-0.52, P=0.006), while no statistically significant correlation was found in the bilateral group (Spearman correlation coefficient, r = -0.141, P=0.458).
Limb length discrepancy affects functional outcome after total knee arthroplasty, especially so in patients of bilateral osteoarthritis with varus deformity undergoing surgery of only one knee.
关于髋关节置换术中肢体长度差异及其对患者功能的影响，已有文献进行了深入讨论，但很少有研究探讨全膝关节置换术（TKA）后肢体长度差异对功能的影响。本研究的目的是确定患有双膝内翻畸形的双侧膝关节骨关节炎患者在TKA后肢体长度差异是否会影响功能结局。
回顾性分析了1996年至2008年期间接受全膝关节置换术的54例患有双膝内翻畸形的双侧膝关节骨关节炎患者。患者分为两组。30例患者（平均年龄64岁）接受了单侧TKA手术，30例患者（平均年龄65.8岁）接受了双侧全膝关节置换术。6例患者接受了分期手术，并被纳入两组，因为两次手术之间的时间间隔超过了本研究规定的最短6个月随访期。测量了肢体长度差异，并与膝关节协会评分的功能部分进行了统计学相关性分析。
在单侧组（n = 30）中，平均肢体长度差异为1.53 cm（范围：0 - 3 cm），平均功能评分为73分（范围：45 - 100分）。在双侧组（n = 30）中，平均肢体长度差异为0.5 cm（范围：0 - 2 cm），平均功能评分为80.67分（范围：0 - 100分）。在单侧组中，发现肢体长度差异与功能评分之间存在统计学显著的负相关性（Spearman相关系数，r = -0.52，P = 0.006），而在双侧组中未发现统计学显著相关性（Spearman相关系数，r = -0.141，P = 0.458）。
肢体长度差异会影响全膝关节置换术后的功能结局，尤其是对于仅接受一侧膝关节手术的双膝内翻畸形双侧膝关节骨关节炎患者。
