Goldstein Zachary H, Yi Paul H, Batko Brian, Kearns Sean, Tetreault Matthew W, Levine Brett R, Della Valle Craig J, Sporer Scott M
Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL.
Am J Orthop (Belle Mead NJ). 2016 Nov/Dec;45(7):E429-E433.
Leg length discrepancy (LLD) is common after total knee arthroplasty (TKA) although its incidence has not been well documented. The purpose of this study was to determine the incidence of perceived LLD before and after primary total knee arthroplasty as well as to determine the correlation between mechanical axis of the knee and perceived LLD. The incidence and time frame of resolution of postoperative LLD was also assessed. Seventy-three patients were prospectively enrolled. Evaluation included patient surveys regarding perceived LLD preoperatively, and at 3- to 6-week, 3-month, 6-month, and 1-year visits. Mechanical axis radiographs were obtained and the relationship of mechanical axis in patients with and without perceived LLD, both before and after surgery, was determined. Analysis was also performed for separate varus and valgus deformities. The effect of surgery on patients' perception of LLD was also determined. Fifty-three patients did not perceive a LLD preoperatively and 18 perceived a LLD preoperatively. Sixty-four patients did not perceive a LLD postoperatively and 7 patients perceived a LLD postoperatively. There was a significant difference in patients who perceived LLD preoperatively and those who perceived LLD postoperatively (P = .035). Of the 7 patients with a perceived LLD postoperatively, all noted resolution of LLD at a mean of 8.5 weeks. There were no statistically significant correlations of knee alignment to perceived LLD in any patient groups. Body mass index and age did not demonstrate any statistical differences between patient groups. Perceived LLD is common in patients undergoing TKA; however, perceived LLD decreases after surgery. Although approximately 10% of patients perceive a LLD after surgery, the vast majority resolve within 3 months. Our study did not show any relationship between mechanical knee alignment and perception of LLD.
全膝关节置换术（TKA）后肢体长度差异（LLD）很常见，尽管其发生率尚无充分记录。本研究的目的是确定初次全膝关节置换术前和术后感觉肢体长度差异的发生率，并确定膝关节机械轴与感觉肢体长度差异之间的相关性。还评估了术后肢体长度差异消失的发生率和时间范围。前瞻性纳入了73例患者。评估包括术前以及术后3至6周、3个月、6个月和1年随访时患者关于感觉肢体长度差异的调查。获取机械轴位X线片，确定手术前后有和没有感觉肢体长度差异的患者的机械轴关系。还对单独的内翻和外翻畸形进行了分析。还确定了手术对患者肢体长度差异感知的影响。53例患者术前未感觉到肢体长度差异，18例术前感觉到肢体长度差异。64例患者术后未感觉到肢体长度差异，7例患者术后感觉到肢体长度差异。术前感觉到肢体长度差异的患者与术后感觉到肢体长度差异的患者之间存在显著差异（P = 0.035）。在7例术后感觉到肢体长度差异的患者中，所有患者均指出平均在8.5周时肢体长度差异消失。在任何患者组中，膝关节对线与感觉肢体长度差异均无统计学上的显著相关性。患者组之间的体重指数和年龄无统计学差异。接受全膝关节置换术的患者中感觉肢体长度差异很常见；然而，术后感觉肢体长度差异会减少。尽管约10%的患者术后感觉到肢体长度差异，但绝大多数在3个月内消失。我们的研究未显示膝关节机械对线与肢体长度差异感知之间存在任何关系。
