Veeger H E J, Rozendaal L A, van der Helm F C T
Department of Human Movement Sciences, Institute for Fundamental and Clinical Human Movement Sciences, Vrije Universiteit Amsterdam, van der Boechorststraat 9, 1081 BT Amsterdam, The Netherlands.
Clin Biomech (Bristol). 2002 Mar;17(3):211-8. doi: 10.1016/s0268-0033(02)00008-6.
To assess the mechanical load on the glenohumeral joint and on shoulder muscles during wheelchair propulsion at everyday intensities.
Model simulations based on experimental input dataBackground. Virtually nothing is known about the mechanical load on the upper extremity during wheelchair propulsion. Hand rim wheelchair propulsion is a significant risk factor for shoulder pain and injury among wheelchair users. A musculoskeletal model of the upper extremity during wheelchair propulsion will quantify the stresses placed on anatomic structures and may provide insight into the source of symptoms and injuries.
Three experienced wheelchair users underwent wheelchair exercise tests at combinations of two load levels (10 and 20 W) and two velocities (0.83 and 1.39m.s(-1)) during which input data were collected for a musculoskeletal model of the upper extremity. The model was then used for the estimation of the glenohumeral contact force, as well as individual muscle forces.
Peak glenohumeral contact forces were between 800 and 1400 N (100-165% body weight) and differed significantly between load levels. Averaged over the push phase, these forces were 500-850 N. In absolute terms the m. deltoideus and rotator cuff muscles were highly active (>100N). In relative terms the load on the m. supraspinatus was high, with peak values of over 50% of its maximum attainable force.
Low intensity wheelchair propulsion does not appear to lead to high contact forces. The muscle forces in the rotator cuff and especially in the m. supraspinatus are high. This might indicate a risk for muscle damage and the subsequent development of shoulder complaints, such as rotator cuff tears.
Within the wheelchair user population, there is a high prevalence of upper extremity complaints. Not much is known about the causes of those complaints. Wheelchair propulsion is likely to be a major risk factor. If the (nature of this) mechanical load can be identified, specific exercise programs and/or design changes can be better tuned to prevent overuse injuries.
评估日常强度轮椅推进过程中盂肱关节和肩部肌肉的机械负荷。
基于实验输入数据的模型模拟。背景。关于轮椅推进过程中上肢的机械负荷几乎一无所知。手动轮圈轮椅推进是轮椅使用者肩部疼痛和损伤的重要危险因素。轮椅推进过程中上肢的肌肉骨骼模型将量化施加在解剖结构上的应力，并可能深入了解症状和损伤的根源。
三名经验丰富的轮椅使用者在两种负荷水平（10瓦和20瓦）和两种速度（0.83米/秒和1.39米/秒）的组合下进行轮椅运动测试，在此期间收集上肢肌肉骨骼模型的输入数据。然后使用该模型估计盂肱接触力以及各个肌肉的力量。
盂肱接触力峰值在800至1400牛之间（体重的100%-165%），且负荷水平之间存在显著差异。在推进行阶段平均，这些力为500-850牛。就绝对值而言，三角肌和肩袖肌肉高度活跃（>100牛）。就相对值而言，冈上肌的负荷很高，峰值超过其最大可承受力的50%。
低强度轮椅推进似乎不会导致高接触力。肩袖尤其是冈上肌的肌肉力量很高。这可能表明存在肌肉损伤风险以及随后出现肩部问题，如肩袖撕裂。
在轮椅使用者群体中，上肢问题的患病率很高。对于这些问题的原因了解不多。轮椅推进可能是一个主要危险因素。如果能够确定这种机械负荷的（性质），可以更好地调整特定的锻炼计划和/或设计更改以预防过度使用损伤。
