LAUSR

Background Muscle Velocity Recovery Cycles (MVRCs) provide information about muscle membrane properties and can reveal disease-related changes. The aim of this study was to test whether the MVRCs could detect muscle membrane changes in diabetic polyneuropathy (DPN). Methods We included 49 patients with diabetes mellitus type-II and 25 age-matched healthy subjects (HS). In addition to conventional nerve conduction studies (NCS), MVRCs in anterior tibial muscle (TA) was done in all participants. The MVRC parameters evaluated were muscle relative refractory period, early supernormality and late supernormality. MVRC parameters between patients and HC were compared using parametric t-test. Results DPN diagnosis was given if NCS showed at least two abnormal nerves, one should be the sural nerve. Of 49 diabetics, 24 patients (42%) had DPN (DPN+) and 25 patients (48%) did not show neuropathy (DPN−). None of the MVRC parameters differed between DPN+ patients and HC. Additionally, there was no statistically significant difference between HC and DPN− patients or DPN+ and DPN− patients (t-test, p > 0.05). Conclusions The finding of no difference in MVRC in patients with neuropathy compared to healthy controls and patients without neuropathy may indicate that the muscle fiber membranes are not prominently affected by the denervation process. This may be explained by the compensatory process of collateral reinnervation. Another possible explanation is that the affection in anterior tibial muscle is not prominent due to length dependent feature of DPN.