Disordered mobility of large joints in association with neuropathy in patients with long-standing insulin-dependent diabetes mellitus.

Movement performance was studied in 29 long-term patients with insulin-dependent diabetes mellitus (IDDM) and 29 matched control subjects. Velocity, range of motion, reaction time, and strength of ankle dorsal and plantar flexion and knee extension were measured. The neuropathic condition was assessed from clinical examination, nerve conduction studies, and quantitative sensory examination, and summed to obtain a neuropathy rank-sum score. Reaction time for the diabetic patients was increased by 29%, 23%, and 22% for ankle dorsal, ankle plantar, and knee extension movements respectively (p < 0.001). Range of motion was slightly decreased at ankle dorsal flexion (12%, p < 0.05). There was an inverse relationship between range of motion and neuropathy rank-sum score for ankle dorsal (r = -0.68, p < 0.001) and plantar flexion (r = -0.61, p < 0.001). Peak velocity was significantly decreased at ankle dorsal (21%, p < 0.001) and plantar flexion (23%, p < 0.001) and was related to the isokinetic muscle strength. Peak velocity was also related to the neuropathy rank-sum score at ankle dorsal flexion (r = 0.57, p < 0.002). We conclude that maximal movements at the ankle are delayed and slowed in long-term IDDM patients. The decreased peak velocity and the range of motion are related to the severity of neuropathy.