全髋关节置换术下肢不等长的处理

目的 探讨全髋关节置换术下肢不等长的处理方法。方法 1997年 7月～ 2000年 7月，将 44例接受单侧全髋关节置换术的患者作为研究对象；男 30例，女 14例。患者手术时年龄 42～ 80岁，平均 65.8岁。术前通过临床及对骨盆前后位 X线片的测量评估双下肢不等长的程度，然后利用模板预测髋臼及股骨假体的置入位置，估计股骨颈的截骨水平以维持双下肢等长。术中先标记并测量股骨近端至髋臼上方两标志之间的距离，而后在术前估计的位置进行股骨颈截骨。置入假体试模之后再次测量两标志之间的距离，最后通过调整股骨头假体颈部或头部长度进一步进行纠正。结果 术前患肢短缩 1.5～ 5.0 cm的 30例患者中，术后仅 4例患肢短缩或延长在 1.5～ 2.0 cm之间。术前双下肢等长 14例患者中，术后仅 1例患侧延长超过 1.0 cm。结论 通过术前测量评估，预测股骨颈截骨平面，术中定位测量，置入假体试模后再次测量，调整股骨头假体颈部及头部长度等方法，可以有效地避免全髋关节置换术带来的下肢不等长，同时也可纠正术前存在的下肢短缩现象。

Management of limb length discrepancy during total hip replacement

Objective To investigate the management of limb length discrepancy during total hip replacement. Methods Forty-four hips of 44 patients undergone unilateral primary total hip replacement between July 1997 and July 2000 were included in this study. There were 30 males and 14 females. The ages of the patients at the surgery ranged from 42 to 80 years(mean, 65.8 years). Evaluation of the limb length discrepancy through clinical measurements and radiographic templates was done preoperatively to anticipate the optimal implantation position of the components and determine the level of expected femoral neck cut to maintain the equality of the limbs. During the surgery, the distance between two reference points made at pelvis and femur were measured before femoral neck osteotomy was performed based on preoperatively estimated parameters. The distance between the two points was measured again after insertion of the trail components in order to adjust the offsets of the femoral neck and head. Results Of the 30 patients with shortened limb ranging 1.5 to 5 cm preoperatively, only 4 had limb length discrepancy between 1.5 and 2 cm after surgery. Of the 14 patients with equal limb length preoperatively, only one limb had been lengthened more than 1.0 cm postoperatively compared with its contralateral limb. Conclusion The preoperative measurements, templating and intraoperative corrections are helpful in minimizing limb length discrepancy during total hip replacements and correcting preoperative limb length discrepancy as well.