Ultrasound shows atrophy of foot muscles in patients with diabetes

Ultrasound could stand in for MRI in evaluating muscle atrophy in diabetic patients, with the advantage of being a bedside tool, according to Danish researchers.

Dr. Kaare Severinsen in neurology and colleagues in the neuroradiology department of Aarhus University Hospital in Denmark performed ultrasound exams on two muscles in the feet of 26 diabetic patients and 26 matched controls. They also measured the volume of all foot muscles using volumetric functional MRI and established their clinical condition by testing nerve conduction and sensory perception thresholds. They published their study in Diabetes Care online ahead of print on Aug. 23, 2007.

With ultrasound, the researchers found extensor digitorum brevis muscles had a mean width of 6.4 ± 2.1 mm in diabetic patients and a mean cross-sectional area of 116 ± 65 mm². This showed significant atrophy versus the mean width of 9 ± 1 mm and mean cross-sectional area of 214 ± 38 mm² in controls.

The muscles of the first interstitium showed similar results, with a mean width of 29.6 ± 8.3 mm in diabetic patients and 40.2 ± 3.6 mm in controls.

The volume of the muscles as measured by MRI had a high correlation to the ultrasound measurements. Ultrasound showed both the extensor digitorum brevis muscle and the muscles of the first interstitium were thinner in neuropathic diabetic patients than in those without neuropathy.

The researchers concluded that ultrasound can show atrophy in muscles in the feet. It closely relates to MRI measurements and clinical indications of neuropathy in diabetic patients and could be useful as a beside test.