Ezquerra Laura, Quilez María Paz, Pérez María Ángeles, Albareda Jorge, Seral Belén
Department of Orthopaedic Surgery, University Hospital Lozano Blesa, San Juan Bosco, 15, 50009 Saragossa, Spain.
C/El Greco, 150, Urbanización Virgen de la Columna, 50730 El Burgo de Ebro, Saragossa, Spain.
J Med Biol Eng. 2017;37(1):26-34. doi: 10.1007/s40846-016-0210-4. Epub 2017 Jan 21.
Dislocation is a serious complication in total hip replacement (THR). An inadequate range of movement (ROM) can lead to impingement of the prosthesis neck on the acetabular cup; furthermore, the initiation of subluxation and dislocation may occur. The objective of this study was to generate a parametric three-dimensional finite element (FE) model capable of predicting the dislocation stability for various positions of the prosthetic head, neck, and cup under various activities. Three femoral head sizes (28, 32, and 36 mm) were simulated. Nine acetabular placement positions (abduction angles of 25°, 40° and 60° combined with anteversion angles of 0°, 15° and 25°) were analyzed. The ROM and maximum resisting moment (RM) until dislocation were evaluated based on the stress distribution in the acetabulum component. The analysis allowed for the definition of a "safe zone" of movement for impingement and dislocation avoidance in THR: an abduction angle of 40°-60° and anteversion angle of 15°-25°. It is especially critical that the anteversion angle does not fall to 10°-15°. The sequence of the RM is a valid parameter for describing dislocation stability in FE studies.
脱位是全髋关节置换术（THR）中的一种严重并发症。活动范围（ROM）不足会导致假体颈部撞击髋臼杯；此外，还可能引发半脱位和脱位。本研究的目的是生成一个参数化三维有限元（FE）模型，该模型能够预测在各种活动下假体头、颈和髋臼杯处于不同位置时的脱位稳定性。模拟了三种股骨头尺寸（28、32和36毫米）。分析了九个髋臼放置位置（外展角度为25°、40°和60°，并与前倾角0°、15°和25°相结合）。根据髋臼组件中的应力分布评估脱位前的ROM和最大阻力矩（RM）。该分析确定了THR中避免撞击和脱位的“安全运动区”：外展角度为40° - 60°，前倾角为15° - 25°。特别关键的是前倾角不能降至10° - 15°。RM序列是有限元研究中描述脱位稳定性的有效参数。
