Crowe IV 型髋关节发育不良全髋关节置换术前计算机辅助设计

 目的 探索采用计算机辅助技术, 对接受全髋关节置换(total hip arthroplasty, THA)的 Crowe IV型髋关节发育不良患者进行术前评估, 确定髋臼大小、骨缺损程度, 并在此基础上辅助手术设 计、假体选择及骨缺损修复。 方法2011 年3 月至10 月, 共10 例(13 髋)Crowe IV型高位脱位髋关节发 育不良患者接受THA 治疗。患者均为女性;年龄32~74 岁, 平均42 岁。所有患者术前行髋关节三维CT 扫描, 然后将扫描数据输入SuperImage 软件重建骨盆及髋臼。重建后在不同角度精确评估真臼位置, 测 量真臼大小及前后柱厚度, 评估骨缺损程度;将髋臼试模、骨缺损修复材料(钽金属垫块)按1颐1 大小扫 描输入计算机系统, 进行术前模拟安放, 确定髋臼假体大小、安放位置;髋臼假体安放后评估遗留的骨缺 损, 确定骨缺损修复材料, 进行骨缺损修复模拟测试。 结果 9 例(12 髋)术中实际安放髋臼假体型号与 术前计算机辅助设计一致, 1 例(1髋)假体型号较术前设计大一号。所有患者髋臼安放位置与术前计划 一致, 均安放于真臼。髋臼骨缺损修复按术前设计:4 髋因髋臼顶部骨缺损明显(臼顶部骨性覆盖 < 70%), 采用钽金属垫块修复骨缺损, 以增强髋臼的稳定性;7 髋采用Harris 法自体股骨头植骨修复骨缺 损;2 髋髋臼杯植入后臼顶覆盖可, 术中未植骨。 结论 对Crowe IV型髋关节发育不良者行计算机辅助 下THA术前设计, 有助于术前精确评估真臼发育情况、大小及髋臼骨缺损, 提高手术治疗精确性。

Computer-aided acetabular evaluating and operation designing before total hip arthroplasty for Crowe IV developmental dysplasia of the hip

Objective To explore the effect of computer-aided acetabular evaluating and operation designing before total hip arthroplasty (THA) for Crowe IV developmental dysplasia of the hip (DDH). Methods From March 2011 to October 2011, 10 patients (13 hips) diagnosed as DDH (Crowe IV) underwent THA. Before operation, all 10 patients underwent three dimensional (3D) CT scanning and the information was inputted into the SuperImage system to reconstitute the 3D anatomic models of pelvis and acetabulum.
Then the position and size of the true acetabulum, the thickness of the anterior and posterior columns, and the degree of bone defect were evaluated or measured exactly with computer assisted design (CAD) software.
After inputting the information of the test model of the acetabulum and material for repairing bone defect into the CAD software, the implantation of the acetabular prosthesis was simulated to determine the size and position of the acetabular prosthesis. Then the bone defect was evaluated after implantation of the acetabulum to perform simulation test of restoration of bone defect. Eventually, orthopedic surgery was performed precisely. Results The size of acetabular prosthesis implanted in the operation was coincident with that got by preoperative computer aided technology in 9 patients (12 hips), and one acetabular prosthesis was larger than that designed preoperatively. All the cups were implanted in the anatomic acetabular location. The bone defect in the acetabular roof was reconstructed with tantalum augments in 4 hips, with Harris autograft using autologous femoral head in 7 hips, which were coincident with that designed preoperatively. Conclusion The preoperative CAD is useful in THA for Crowe IV DDH, because it can exactly evaluate the developmental condition of the true acetabulum.