Ross Bailey J, Patel Akshar H, Wilder J Heath, Weldy John M, Dranoff Charles S, Weintraub Matthew J, Kim Nathan E, Wang Hao, Sherman William F
Department of Orthopaedic Surgery, Tulane University School of Medicine, New Orleans, LA, USA.
Department of Biomedical Engineering, Tulane University School of Science & Engineering New Orleans, LA, USA.
Arthroplast Today. 2022 Apr 4;15:47-54. doi: 10.1016/j.artd.2022.02.007. eCollection 2022 Jun.
The purpose of this study was to compare the biomechanical strength of femurs before an iatrogenic periprosthetic fracture vs after an initial fracture with supporting cerclage fixation during cementless total hip arthroplasty.
Nineteen composite femurs and 5 matched pairs of cadaveric femurs were implanted with a single-wedge or dual-wedge tapered femoral stem and tested for ultimate load to failure producing a periprosthetic fracture. Following initial fracture, each femur was cerclaged with Vitallium cables and retested for ultimate load to failure. The mean force eliciting iatrogenic fracture before cabling and that after cabling were compared with a two-sided paired Student's t-test.
All composite femurs developed periprosthetic fractures with an average length extension from the calcar of 75.17 mm. For the 19 composite femurs, the mean ultimate load to failure before cabling and that after cabling were not significantly different (2422.95 N vs 2505.14 N, = .678). For the 10 cadaveric femurs, the mean ultimate load to failure for the initial fracture vs that after cabling was statistically comparable (5828.62 N vs 7002.63 N, = .126). Subanalysis of the 5 cadaveric femurs with a double-wedge stem revealed a significantly higher mean load to failure following cabling (5007.38 N vs 7811.17 N, = .011).
Biomechanical strength was similar for femurs that sustained an initial iatrogenic periprosthetic fracture and the same femurs cabled with cerclage wires after being fractured. These data may assist in operative decision-making for treating iatrogenic fractures during total hip arthroplasty.
本研究的目的是比较在非骨水泥型全髋关节置换术中，医源性假体周围骨折发生前股骨的生物力学强度与初次骨折后采用支撑环扎固定时股骨的生物力学强度。
将19根复合股骨和5对匹配的尸体股骨植入单楔或双楔锥形股骨干，并测试导致假体周围骨折的极限破坏载荷。初次骨折后，用维塔利姆合金缆线对每根股骨进行环扎，并再次测试极限破坏载荷。采用双侧配对学生t检验比较缆线固定前和固定后引起医源性骨折的平均力。
所有复合股骨均发生假体周围骨折，从股骨距处的平均长度延伸为75.17mm。对于19根复合股骨，缆线固定前和固定后的平均极限破坏载荷无显著差异（2422.95N对2505.14N，P = 0.678）。对于10根尸体股骨，初次骨折时与缆线固定后的平均极限破坏载荷在统计学上具有可比性（5828.62N对7002.63N，P = 0.126）。对5根采用双楔柄的尸体股骨进行亚分析发现，缆线固定后平均破坏载荷显著更高（5007.38N对7811.17N，P = 0.011）。
初次发生医源性假体周围骨折的股骨与骨折后用环扎钢丝固定的同一股骨的生物力学强度相似。这些数据可能有助于全髋关节置换术中治疗医源性骨折的手术决策。
