Annu Int Conf IEEE Eng Med Biol Soc. 2021 Nov;2021:4863-4866. doi: 10.1109/EMBC46164.2021.9630149.
Pain in the lower back is frequent problem for most individuals with transfemoral amputation, which limits their overall mobility and quality of life. While the underlying root causes of back pain are multifactorial, a contributing factor is the mechanical loading environment within the lumbopelvic joint. Specifically, this study aims to explore the upstream effects amputation has on the mechanical loading environment of the lumbopelvic joint using a 3D musculoskeletal model of transfemoral amputation. A generic musculoskeletal model was altered to represent a transfemoral amputation. Muscle parameters were adjusted to represent a myodesis amputation surgery that preserved musculotendon tension in a neutral anatomical pose. The model contained a total of 28 degrees of freedom and 76 muscles spanning the lower-limb and torso. In forward dynamics simulations, generalized external forces were applied to the distal end of the residual limb at a series of directions. Axial, oblique and transverse 10 N end-limb loads were applied. In addition, simulations were performed for 0°, 4°, and 8° of femur abduction, which are clinically observed in individuals with transfemoral amputation. In these simulations, reaction forces and moments at the lumbopelvic joint were computed. In general, femur abduction had little effect on back loading for an axial applied end-limb force. These data showed that while the individual magnitudes of lumbopelvic force and moment reactions did not significantly deviate for differing levels of femur abduction, the pattern of how these forces changes in response to different end-limb force directions (applied circumferentially along the limb) was affected by femur abduction angle.Clinical Relevance- The changes in joint reaction forces in the lumbopelvic joint from an aligned position to an abducted position reinforce the importance of avoiding hip flexion-abduction contracture during amputation surgery. This suggests that surgical techniques such as myodesis, osseointegration, or medial thighplasty, which intend to maintain anatomical alignment may have beneficial upstream effects for the patients during locomotion. Given the prevalence of lower back pain in individuals with transfemoral amputation, teasing out the causes of lower back pain could bring relief to a population that struggles with community independence.
下背部疼痛是大多数股骨截肢患者的常见问题，这限制了他们的整体活动能力和生活质量。虽然背痛的根本原因是多因素的，但一个促成因素是腰骶关节的机械加载环境。具体来说，本研究旨在使用股骨截肢的三维肌肉骨骼模型探索截肢对上腰椎关节机械加载环境的上游影响。对通用肌肉骨骼模型进行了修改，以代表股骨截肢。肌肉参数进行了调整，以代表保留中立解剖姿势下肌肌腱张力的肌切除术。该模型总共包含 28 个自由度和 76 块肌肉，跨越下肢和躯干。在正向动力学模拟中，在一系列方向上向残肢的远端施加广义外部力。施加了轴向、斜向和横向的 10N 末端肢体负荷。此外，还对股骨外展 0°、4°和 8°进行了模拟，这些在股骨截肢患者中临床观察到。在这些模拟中，计算了腰骶关节的反作用力和力矩。一般来说，股骨外展对轴向施加的末端肢体力的背部负荷影响不大。这些数据表明，虽然不同股骨外展水平下腰骶力和力矩反作用力的个体大小没有显着差异，但这些力响应不同末端肢体力方向（沿肢体周向施加）变化的模式受股骨外展角度的影响。临床意义-从对齐位置到外展位置，腰骶关节的关节反作用力的变化强调了在截肢手术中避免髋关节屈曲-外展挛缩的重要性。这表明，旨在保持解剖对齐的手术技术，如肌切除术、骨整合或大腿内侧整形术，可能对运动中的患者具有有益的上游影响。鉴于股骨截肢患者下腰痛的普遍性，梳理下腰痛的原因可能会为那些努力实现社区独立的人群带来缓解。
