Dorr L D, Tawakkol S, Moorthy M, Long W, Wan Z
University of Southern California Center for Arthritis and Joint Implant Surgery, Los Angeles 90033, USA.
J Bone Joint Surg Am. 1999 Jan;81(1):83-92. doi: 10.2106/00004623-199901000-00012.
Twenty-four hip replacements were performed with use of a medial protrusio technique to stabilize the fit of a hemispherical metal shell in the acetabulum in nineteen patients who had dysplasia of the hip. All of the hips were followed for a minimum of five years (average, seven years; range, five to thirteen years). Six of the hips were type I, seven were type II, eight were type III, and three were type IV according to the criteria of Crowe et al. The acetabular cup was implanted with the medial aspect of its dome beyond the Kohler line (drawn from the ischium along the ilioischial line) in all hips. An autogenous graft sculpted from the femoral head was used to cover 15 to 30 percent of the superolateral portion of the cup in one type-I hip, four type-III hips, and one type-IV hip. The need for these six bone grafts could have been avoided by reaming two to three millimeters more medially or by allowing 20 percent of the superolateral portion of the cup to be uncovered. Sixty to 84 percent of each bone graft was resorbed, effectively leaving the superolateral portion of the cup uncovered. The amount of the surface of the cup that was beyond the Kohler line averaged 41 percent for the six type-I hips, 43 percent for the seven type-II hips, 41 percent for six of the type-III hips, and 44 percent for one of the type-IV hips. Crossing of the ilioischial and iliopubic lines was noted on the radiographs of two type-III and two type-IV hips. Radiographs of two type-I hips and one type-II hip showed 7 to 17 percent of the surface of the dome of the cup through the internal pelvic wall (beyond the iliopubic line). None of the twenty-four metal shells were revised. A reoperation was performed on two hips to exchange a worn polyethylene insert, and three femoral components that had been fixed without cement were revised because of mechanical loosening. Wear averaged 0.26 millimeter per year in the fourteen hips that had a titanium femoral head and 0.09 millimeter per year in the nine hips that had a cobalt-chromium femoral head. The remaining hip had a ceramic femoral head, and the wear rate was 0.09 millimeter per year. The medial protrusio technique is a predictable, reproducible method for obtaining fixation of a porous-coated, hemispherical acetabular component in a dysplastic acetabulum. The technique permits the use of a porous-coated (bone-ingrowth) component; avoids the use of support bone graft and thereby reduces the operative time; facilitates rehabilitation by permitting earlier weight-bearing of the hip; and permits the use of a modular bearing surface, which may allow future exchange of only this surface rather than revision of the entire acetabular component because of excessive wear.
对19例髋关节发育不良患者采用内侧突出技术进行了24例髋关节置换术，以稳定半球形金属髋臼杯在髋臼中的贴合。所有髋关节均随访至少5年（平均7年；范围5至13年）。根据Crowe等人的标准，其中6例髋关节为I型，7例为II型，8例为III型，3例为IV型。所有髋关节的髋臼杯均以其穹顶内侧部分超出科勒线（从坐骨沿髂坐线画出）的方式植入。在1例I型髋关节、4例III型髋关节和1例IV型髋关节中，采用从股骨头雕刻的自体骨移植覆盖髋臼杯上外侧部分的15%至30%。通过在内侧多扩孔2至3毫米或允许髋臼杯上外侧部分20%不覆盖，这6例骨移植本可避免。每例骨移植的60%至84%被吸收，实际上使髋臼杯上外侧部分未被覆盖。6例I型髋关节的髋臼杯超出科勒线的表面面积平均为41%，7例II型髋关节为43%，8例III型髋关节中的6例为41%，1例IV型髋关节为44%。在2例III型和2例IV型髋关节的X线片上观察到髂坐线和髂耻线交叉。2例I型髋关节和1例II型髋关节的X线片显示髋臼杯穹顶表面的7%至17%透过骨盆内壁（超出髂耻线）。24个金属髋臼杯均未翻修。对2例髋关节进行了再次手术以更换磨损的聚乙烯内衬，3例非骨水泥固定的股骨部件因机械松动而翻修。14例使用钛股骨头的髋关节磨损平均每年0.26毫米，9例使用钴铬合金股骨头的髋关节磨损平均每年0.09毫米。其余1例髋关节使用陶瓷股骨头，磨损率为每年0.09毫米。内侧突出技术是一种可预测、可重复的方法，用于在发育不良的髋臼中固定多孔涂层半球形髋臼部件。该技术允许使用多孔涂层（骨长入）部件；避免使用支撑骨移植，从而减少手术时间；通过允许髋关节更早负重促进康复；并允许使用模块化承重表面，这可能使未来仅因过度磨损而只需更换该表面而非整个髋臼部件。
