Quantitation of the alternate movement rate in normal and diabetic subjects

Functional abnormalities of alternate movement rate (AMR) of finger and foot tapping were quantitated in 162 patients with diabetic neuropathy and 30 control subjects using a simple electronic device. The quantitative AMR (QAMR) averaged 29.5 +/- 3.0 for finger tapping and 20.4 +/- 3.7 for foot tapping in controls, and 27.5 +/- 4.8 (P less than 0.05) and 17.0 +/- 5.6 (P less than 0.005) for finger and foot, respectively, in diabetic patients. Fifty-one patients had abnormal QAMR in the finger and 79 in the foot. The QAMR values correlated with the results of nerve conduction studies of patients. Testing for abnormalities of AMR is a useful addition to the testing of dysfunction secondary to diabetic neuropathy. It provides quantitation of a common, subject-initiated, functional task more accurately than possible by clinical observation.