Department of Neurology, Aarhus University Hospital, Aarhus C, Denmark.
Diabetes Metab Res Rev. 2012 Feb;28 Suppl 1:89-92. doi: 10.1002/dmrr.2257.
Neuropathy is a frequent complication in diabetes and most commonly seen as distal symmetrical sensorimotor polyneuropathy (PN). Involvement of the motor system is infrequently seen at the clinical examination. However, with the application of quantitative techniques, that is, isokinetic dynamometry, type 1 and type 2 diabetic patients have been detected to have weakness at the ankle and the knee. Muscle weakness is found only in diabetic patients with PN, while non-neuropathic patients even with long-term diabetes have normal strength. The weakness is closely related to signs and severity of PN. With the use of magnetic resonance imaging, muscle weakness is found to be paralleled by muscular atrophy, which is observed in the feet and at the lower leg. Following diabetic patients for 8-10 years, we have observed accelerated loss of muscle strength in patients with symptomatic PN; similarly, accelerated loss of muscle mass is observed in the feet and lower legs. In large-scale studies of diabetic and non-diabetic subjects, lower muscle quality in diabetic patients is also found. Thus, in addition to PN, diabetes per se leads to lower strength per unit striated muscle. Muscle weakness is related to the slowing of movements, unstable gait, and more frequent falls. Furthermore, motor dysfunction leads to an increased risk of developing a foot ulcer due to due to alterations of the biomechanics of the feet caused by muscle atrophy. This may lead to an increased skin pressure that may lead to foot ulceration and ultimately amputation. Muscle and balance training may improve strength, postural stability, and walking performance; however, this needs to be studied in more detail.
神经病变是糖尿病的常见并发症，最常见的表现为远端对称性感觉运动多发性神经病（PN）。运动系统受累在临床检查中很少见。然而，随着定量技术的应用，即等速动力学测定，1 型和 2 型糖尿病患者已被发现存在踝关节和膝关节无力。肌肉无力仅见于有 PN 的糖尿病患者，而无神经病变的患者，即使糖尿病病史较长，其肌力也正常。肌无力与 PN 的体征和严重程度密切相关。使用磁共振成像发现，肌肉无力与肌肉萎缩平行，在足部和小腿观察到肌肉萎缩。对糖尿病患者进行 8-10 年的随访观察发现，有症状的 PN 患者的肌肉力量丧失加速；同样，足部和小腿的肌肉量也会加速减少。在对糖尿病患者和非糖尿病患者的大规模研究中，也发现糖尿病患者的肌肉质量较低。因此，除了 PN 之外，糖尿病本身也会导致单位横纹肌力量下降。肌肉无力与运动速度减慢、步态不稳定和跌倒频率增加有关。此外，运动功能障碍会导致足部生物力学发生改变，从而增加足部溃疡的风险，因为肌肉萎缩会导致足部溃疡。肌肉和平衡训练可以提高力量、姿势稳定性和行走能力；然而，这需要更详细地研究。
