[Central loop versus conventional H-reflex in diabetic neuropathic patients]

ABSTRACT

Diabetes mellitus is the most prevalent endocrine disease and one of the most common causes of peripheral neuropathy. Neither conventional electrodiagnostic nor imaging studies [even MRI of lumbosacral vertebrae] can precisely differentiate concomitant radiculopathy [e.g. S[1]-root irritation] and diabetic peripheral polyneuropathy. This usually leads to unnecessary surgical interventions and its complications. In this study, S[1]-roots of diabetic neuropathic patients with impaired conventional H-reflexes were evaluated by the central loop of gastrocnemius-soleus H-reflexes. This descriptive study was performed in the clinics of Shiraz medical school in 1387[2008]. Forty two diabetic patients [14 males and 28 females with a mean age of 48.2 years] with unobtainable or abnormal conventional gastrocnemius-soleus H-reflexes and peripheral neuropathy were enrolled. The central loop of H-reflex was performed bilaterally by stimulating S[1]-root with a monopolar needle and recorded in the half way of the line from popliteal crease to the medial malleolus. Collected data were analyzed by McNemar test, using SPSS software. Of 84 limbs with impaired conventional H-reflexes, 82 limbs [97.6%] had the central loop of H-reflexes with latencies less than 8 ms. All the limbs with abnormally prolonged conventional H-reflexes' latencies had the central loop of H-reflexes' latencies in the range of 5.5-7.85 ms. The latency of central loop of H-reflex in this study was 6.34 +/- 0.96 ms with the range of 4.3-7.85 ms. In case the conventional H-reflex is impaired, the central loop of H-reflex in diabetic neuropathic patients offers a valuable approach for investigating S[1]-root. It seems that this approach leads to a better diagnosis of the absence of radiculopathy and a decrease in the rate of unnecessary surgical interventions and its complications in diabetics