Atrophy of Foot Muscles

Abstract

OBJECTIVE -Diabetic neuropathy is a length-dependent process that leads to reduced muscle strength and atrophy of leg muscles in some patients. We hypothesized that intrinsic foot muscles are atrophied in diabetic neuropathy and that the degree of atrophy is a measure of motor dysfunction closely related to the neuropathic process.RESEARCH DESIGN AND METHODS -Consecutive cross-sectional magnetic resonance images of the nondominant foot were obtained for stereological determination of the total volume of the intrinsic foot muscles (VFM) in 23 long-term diabetic patients with (n ϭ 15) and without (n ϭ 8) chronic neuropathy and in 23 matched healthy nondiabetic control subjects. Based on clinical examination, nerve conduction studies, and quantitative sensory examination, a neuropathy rank-sum score was calculated for each patient.RESULTS -Total VFM was 86 Ϯ 52, 165 Ϯ 34, and 168 Ϯ 42 cm 3 in neuropathic patients, nonneuropathic patients, and healthy control subjects, respectively (P Ͻ 0.001). There was a close inverse relationship between the neuropathy rank-sum score and the VFM (r ϭ Ϫ0.75, P Ͻ 1 ϫ 10 Ϫ5 ).CONCLUSIONS -Total volume of the foot muscles is halved in patients with diabetic neuropathy. Atrophy of foot muscles is closely related to the severity of neuropathy and reflects motor dysfunction. Diabetes Care 27:2392-2385, 2004L oss of ankle jerks and of sensation in the feet are early clinical signs of chronic polyneuropathy in diabetes. In contrast, motor weakness with loss of the ability to stand on the heels occurs late in the clinical course and only in a minority of diabetic patients. Previous studies on motor function in diabetic neuropathy have relied on simple clinical tests such as the ability to stand on heels (1) and neurophysiological examinations of motor nerves (2). In a series of experiments in long-term diabetic patients, we have observed that muscle weakness in the lowerleg muscles occurs to a substantial degree in chronic neuropathic patients, closely related to muscle atrophy, whereas nonneuropathic patients have normal muscle strength and striated muscle mass (3). In the more distally situated intrinsic foot muscles, Brash et al. (4) observed atrophy in neuropathic diabetic patients using a specific magnetic resonance imaging (MRI) contrast sequence; however, the atrophy was not quantified. Since diabetic polyneuropathy shows a centripetal pattern of progression, quantification of the more distally situated foot muscles could possibly serve as an early marker for motor dysfunction in diabetic neuropathy.We hypothesized that muscular atrophy is an integral part of diabetic neuropathy that is easily detected in the feet and is closely related to the severity of neuropathy. In the present study, foot muscle volume was studied in a group of longterm diabetic patients with and without neuropathy and in a group of nondiabetic control subjects.RESEARCH DESIGN AND METHODS -Twenty-three type 1 diabetic patients (16 men and 7 women) aged 46 years (median, range 27-62) with a median diabetes durat...

Some Modern Aspects of Etiology and Pathogenesis of Diabetic Foot Syndrome

“…Постоянная травматизация на фоне сниженной способно-сти к заживлению и нарушения микроцирку-ляции способствует образованию трофических язв [2, 7,22].…”

“…Прогрессирование данного заболевания характеризуется комплексом ос-ложнений: кардиопатия, нефропатия, ретино-патия, тяжелейшим из которых является син-дром диабетической стопы (СДС), обуслав-ливающий большинство ампутаций нижних конечностей [2, 3,7].…”

“…Необходимость дальнейшего изучения проблемы сахарного диабета и синдрома диа-бетической стопы вызвана отсутствием обще-принятого, систематизированного комплекс-ного подхода к диагностике и лечению данной патологии [5,7].…”

Role of Skeletal Muscle MRI inPeripheral Nerve Disorders

“…Or it may reflect a demyelinating process, which also shows a length-dependent pattern because longer fibres have a higher probability of conduction block due to demyelination. Recent MRI studies have demonstrated the length-dependent pattern or centripetal progression of muscle denervation in both acquired (Andersen et al, 2004;Andreassen et al, 2009) and hereditary (Gallardo et al, 2006;Chung et al, 2008) forms of polyneuropathy. Diabetic patients commonly develop sensory polyneuropathy with distal pain and sensory loss.…”

“…Diabetic polyneuropathy also leads to denervation and loss of distal muscles. Andersen and colleagues estimated muscle volumes in patients with long-term diabetic polyneuropathy by using a stereological determination method based on cross-sectional T1-weighted MRI (Andersen et al, 2004). The volume of the intrinsic foot muscles was halved in diabetic patients with chronic neuropathy, in comparison with that of diabetic patients without neuropathy.…”