Department of Orthopaedic Surgery, Cedars-Sinai Medical Center, Los Angeles, California.
Baylor St. Luke's Medical Center, Houston, Texas.
J Bone Joint Surg Am. 2018 Feb 7;100(3):226-235. doi: 10.2106/JBJS.16.01501.
Obtaining the ideal acetabular cup position in total hip arthroplasty remains a challenge. Advancements in digital radiography and image analysis software allow the assessment of the cup position during the surgical procedure. This study describes a validated technique for evaluating cup position during total hip arthroplasty using digital radiography.
Three hundred and sixty-nine consecutive patients undergoing total hip arthroplasty were prospectively enrolled. Preoperative supine anteroposterior pelvic radiographs were made. Intraoperative anteroposterior pelvic radiographs were made with the patient in the lateral decubitus position. Radiographic beam angle adjustments and operative table adjustments were made to approximate rotation and tilt of the preoperative radiograph. The target for cup position was 30° to 50° abduction and 15° to 35° anteversion. Intraoperative radiographic measurements were calculated and final cup position was determined after strict impingement and range-of-motion testing. Postoperative anteroposterior pelvic radiographs were made. Two independent observers remeasured all abduction and anteversion angles.
Of the cups, 97.8% were placed within 30° to 50° of abduction, with a mean angle (and standard deviation) of 39.5° ± 4.6°. The 2.2% of cups placed outside the target zone were placed so purposefully on the basis of intraoperative range-of-motion testing and patient factors, and 97.6% of cups were placed between 15° and 35° of anteversion, with a mean angle of 26.6° ± 4.7°. Twenty-eight percent of cups were repositioned on the basis of intraoperative measurements. Subluxation during range-of-motion testing occurred in 3% of hips despite acceptable measurements, necessitating cup repositioning. There was 1 early anterior dislocation.
Placing the acetabular component within a target range is a critical component to minimizing dislocation and polyethylene wear in total hip arthroplasty. Using digital radiography, we positioned the acetabular component in our desired target zone in 97.8% of cases and outside the target zone, purposefully, in 2.2% of cases. When used in conjunction with strict impingement testing, digital radiography allows for predictable cup placement in total hip arthroplasty.
在全髋关节置换术中获得理想的髋臼杯位置仍然是一个挑战。数字放射摄影术和图像分析软件的进步允许在手术过程中评估杯的位置。本研究描述了一种使用数字放射摄影术评估全髋关节置换术中杯位置的经过验证的技术。
前瞻性纳入 369 例接受全髋关节置换术的连续患者。术前仰卧前后骨盆射线照相。术中采用侧卧位进行前后骨盆射线照相。调整射线束角度和手术台以近似术前射线照相的旋转和倾斜。杯位置的目标为外展 30°至 50°，前倾角 15°至 35°。计算术中放射测量值，并在严格的撞击和活动范围测试后确定最终杯位置。术后前后骨盆射线照相。两名独立观察者重新测量了所有外展和前倾角。
97.8%的杯放置在 30°至 50°的外展范围内，平均角度（标准差）为 39.5°±4.6°。2.2%的杯放置在目标区域之外是基于术中活动范围测试和患者因素有意放置的，97.6%的杯放置在前倾角 15°至 35°之间，平均角度为 26.6°±4.7°。根据术中测量值，28%的杯需要重新定位。尽管测量值可接受，但在活动范围测试期间仍有 3%的髋关节出现半脱位，需要重新定位杯。有 1 例早期前脱位。
将髋臼组件置于目标范围内是减少全髋关节置换术中脱位和聚乙烯磨损的关键组成部分。使用数字放射摄影术，我们将髋臼组件定位在我们期望的目标区域内，97.8%的病例位于目标区域内，2.2%的病例位于目标区域外，是有意的。当与严格的撞击测试结合使用时，数字放射摄影术可在全髋关节置换术中实现可预测的杯放置。
