Woolson S T
Palo Alto Medical Clinic, CA 94301.
Orthopedics. 1990 Jan;13(1):17-21. doi: 10.3928/0147-7447-19900101-05.
A method of equalization of leg lengths during total hip replacement surgery was developed which utilizes the concept of equalizing the vertical dimensions of the resected femoral head and neck segment and the remaining hip joint cartilage space, which are removed during the procedure, with the vertical dimensions of the femoral and acetabular prostheses, which are implanted into that void. This was accomplished by determining the dimensions of the prostheses from careful preoperative templating technique and by using a simple arithmetic formula to determine the level of the femoral neck osteotomy. The level of the osteotomy was made by a measurement from the top of the dislocated head of the femur to the medial femoral neck calcar. The radiologic postoperative leg length differences of a consecutive series of 84 patients undergoing primary total hip replacement using this method were determined. The average discrepancy was 2.8 mm. Seventy-five patients (89%) were found to have a postoperative leg length discrepancy of 6 mm (1/4 inch) or less. Six patients (7%) had a discrepancy of 7 to 13 mm, and only three patients (4%) had more than 13 mm (1/2 inch) leg length difference. Using this technique only two patients (2.5%) with unilateral hip replacements had leg lengthening of more than 6 mm.
一种全髋关节置换手术中肢体长度均衡的方法被开发出来，该方法利用在手术过程中被切除的股骨头和颈段以及剩余髋关节软骨间隙的垂直尺寸，与植入该空隙的股骨和髋臼假体的垂直尺寸相等的概念。这是通过术前仔细的模板技术确定假体尺寸，并使用一个简单的算术公式来确定股骨颈截骨水平来实现的。截骨水平通过从脱位的股骨头顶部到股骨内侧颈距进行测量来确定。测定了连续84例采用该方法进行初次全髋关节置换患者术后的放射学肢体长度差异。平均差异为2.8毫米。发现75例患者（89%）术后肢体长度差异为6毫米（1/4英寸）或更小。6例患者（7%）差异为7至13毫米，只有3例患者（4%）肢体长度差异超过13毫米（1/2英寸）。使用该技术，单侧髋关节置换的患者中只有2例（2.5%）肢体延长超过6毫米。
