Accelerated atrophy of lower leg and foot muscles—a follow-up study of long-term diabetic polyneuropathy using magnetic resonance imaging (MRI)

Abstract

Aims/hypothesis The aim of the study was to determine the loss of muscle volume in the lower leg and foot in longterm diabetic patients in relation to the presence of neuropathy. Methods We re-examined 26 type 1 diabetic patients who had participated in magnetic resonance imaging (MRI) studies on muscle volume in the lower leg and foot 9 to 12 years earlier. Re-examination involved MRI, isokinetic dynamometry, clinical examination, electrophysiological studies and quantitative sensory examinations. Results Annual loss of muscle volume of ankle dorsal and plantar flexors was 4.5 (5.5-3.9)% (median [range]) and 5.0 (7.0-4.2)% in neuropathic patients, 1.9 (3.2-1.0)% and 1.8 (2.6-1.3)% in non-neuropathic patients, and 1.7 (2.8-0.8)% and 1.8 (2.4-0.8)% in controls, respectively (p<0.01). Annual change of volume and strength correlated for ankle dorsal flexors (r s =0.73, p<0.01) and for ankle plantar flexors (r s =0.63, p<0.05) in diabetic patients. In addition, annual change of muscle volume for dorsal and plantar flexors was related to the combined score of all measures of neuropathy (r s =−0.68, p<0.02 and r s =−0.73, p<0.01, respectively). Foot muscle volume declined annually by 3.0 (3.4-1.0)% in neuropathic patients and by 1.1 (4.0-0.2)% in non-neuropathic patients, both values being significantly different from controls (0.2 [−2.5 to 2.4]%). Loss of foot muscle volume was related to severity of neuropathy assessed at clinical evaluation (r s =−0.6, p<0.05). Conclusions/interpretation Muscular atrophy in long-term diabetic neuropathy occurs early in the feet, progresses steadily in the lower legs, relates to severity of neuropathy and leads to weakness at the ankle.

Reproducibility, and age, body-weight and gender dependency of candidate skeletal muscle MRI outcome measures in healthy volunteers

“…Conversely these dependencies, if severe, may confound imaging assessment of outcome by masking changes due to disease. In our healthy volunteers, consistent with age-related impaired muscle strength and neurophysiological performance [4, 45], muscle MTR reduced while T 2 and FF increased with age in both thigh and lower leg muscles. Schwenzer et al [25] also demonstrated increases in calf-level FF and T 2 in older subjects, but not MTR.…”

Reduced Lower-Limb Muscle Strength and Volume in Patients With Type 2 Diabetes in Relation to Neuropathy, Intramuscular Fat, and Vitamin D Levels

“…Previous studies have shown atrophy of the ankle plantar and dorsiflexor muscles and knee extensors in patients with diabetic neuropathy compared with patients without neuropathy and control subjects (2,4,6,8). However, the effect on more-proximal leg muscles (knee extensors and flexors), which confer a major effect on postural stability and gait performance, has not been established.…”

Association of diabetic retinopathy with both sarcopenia and muscle quality in patients with type 2 diabetes: a cross-sectional study

“…13 Andreassen et al reported that DN could be involved in the accelerated muscle atrophy of lower extremities, but no difference was observed for the muscle quality between neuropathic and non-neuropathic patients. 14 These findings suggest that DN may have an adverse effect on mobility through sarcopenia in patients with diabetes. Also, DR may be a cause for mobility limitations, and the association between visual impairment and sarcopenia has been reported.…”