Esteki A, Mansour J M
Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106, USA.
Ann Biomed Eng. 1997 May-Jun;25(3):440-51. doi: 10.1007/BF02684185.
Potential hand function in people with tetraplegia was evaluated using a three-dimensional dynamic mathematical model. The model was used to evaluate hand positioning, grasp force, and the outcome of surgeries such as tendon transfers and joint fusion, in situations typical of those encountered when using functional neuromuscular stimulation to restore function in people with tetraplegia. In the model, the hand is treated as a jointed multibody system. Each joint is subjected to muscle moments, passive joint moment, and moments due to grasp forces. Model simulations showed that function was highly dependent on both muscle strength and joint passive moments. The potential for tendon transfers, such as the Zancolli-lasso and intrinsicplasty, plasty, to improve hand function was demonstrated, but their value is subject-dependent. It was also shown that activation of multiple thumb muscles (adductor pollicis, abductor pollicis brevis, and flexor pollicis longus) without interphalangeal joint fusion can provide convenient lateral pinch posture with approximately 70% more grip force than a currently used method, which includes joint fusion but requires only one muscle. Finally, a grasp protocol was introduced and shown successful in palmar grasp and hold of movable cylindrical objects using only extrinsic muscles, provided the fingers could be extended sufficiently to enclose the object.
使用三维动态数学模型评估四肢瘫痪患者的潜在手部功能。该模型用于评估在使用功能性神经肌肉刺激恢复四肢瘫痪患者功能时常见的典型情况下的手部定位、抓握力以及肌腱转移和关节融合等手术的效果。在该模型中，手部被视为一个多关节多体系统。每个关节都受到肌肉力矩、被动关节力矩以及抓握力产生的力矩的作用。模型模拟表明，功能高度依赖于肌肉力量和关节被动力矩。研究证明了诸如赞科利套索手术和固有肌成形术等肌腱转移手术改善手部功能的潜力，但其价值因个体而异。研究还表明，在没有指间关节融合的情况下激活多块拇指肌肉（拇收肌、拇短展肌和拇长屈肌），可以提供便利的侧捏姿势，抓握力比目前使用的方法（包括关节融合但仅需一块肌肉）大约多70%。最后，引入了一种抓握方案，结果表明，只要手指能够充分伸展以包围物体，仅使用外在肌就能成功实现对可移动圆柱形物体的掌侧抓握和握持。
