Department of Orthopaedic Surgery, Martini Hospital, Groningen, The Netherlands.
Int Orthop. 2011 Dec;35(12):1771-6. doi: 10.1007/s00264-011-1233-7. Epub 2011 Mar 4.
We aimed to test the claim of greater range of motion (ROM) with large femoral head metal-on-metal total hip arthroplasty.
We compared 28-mm metal-on-polyethylene (MP) total hip arthroplasty with large femoral head metal-on-metal (MM) total hip arthroplasty in a randomised clinical trial. ROM one year postoperatively was determined in 50 patients. Mean head sizes were 28 mm (MP) and 48 mm (MM).
After one year, the large head MM group showed greater improvement in internal rotation (14 degrees) than the 28 mm group (seven degrees).There were no significant differences in the absolute values of postoperative internal rotation, external rotation, flexion, extension, abduction and abduction.
Absolute postoperative range of motion did not differ between the two groups. The improvement in internal rotation was greater after large femoral head metal-on-metal total hip arthroplasty. It is however questionable whether this difference is clinically relevant.
我们旨在验证大直径金属股骨头金属对金属全髋关节置换术具有更大活动度的说法。
我们在一项随机临床试验中比较了 28mm 金属对聚乙烯（MP）全髋关节置换术与大直径金属股骨头金属对金属（MM）全髋关节置换术。术后一年测量了 50 例患者的活动度。平均股骨头直径分别为 28mm（MP）和 48mm（MM）。
术后一年，大头 MM 组的内旋改善（14 度）大于 28mm 组（7 度）。术后内旋、外旋、屈曲、伸展、外展和外展的绝对值无显著差异。
两组术后的绝对活动度无差异。大头金属对金属全髋关节置换术后的内旋改善更大。然而，这种差异是否具有临床意义是值得怀疑的。
