Timed Vibration Sense and Joint Position Sense Testing in the Diagnosis of Distal Sensory Polyneuropathy

INTRODUCTION: Distal sensory polyneuropathy (DSP) is one of the most common neurological disorders. Although several studies have studied the role of the neurological examination in DSP, there are only limited studies on the utility of timed vibration sense (VBS) and joint position sense (JPS) testing in the diagnosis of DSP. OBJECTIVES: The objective is to study the utility of timed VBS testing and JPS testing at the great toe in clinical detection of DSP. METHODS: This study was prospectively conducted in the neurology department of a tertiary care hospital in India. Patients with DSP referred to the electrophysiology laboratory from August 2017 to December 2017 were screened. Patients with symptomatic DSP which was confirmed by electrophysiological studies were taken as cases and normal participants with no symptoms or electrophysiological findings suggestive of DSP served as controls. RESULTS: We studied 127 patients and 194 controls. The mean age of the patients was 48.7 (14.5) years in the patient group and 39.7 (14.5) years in the control group. The male: female ratio was 77/50 in the patient group and 112/82 in the control group. Abnormal clinical examination was found in 95% of the patients with DSP. The most common abnormal examination components were impaired ankle reflexes (70%), vibration (85%), and JPS (39.6%) sensation. Using the receiver operating characteristic curve for the diagnosis of DSP, a vibratory response lasting <8 s at the great toe had a sensitivity of 85% and specificity of 42.8%. For JPS testing at the great toe, obtaining two or more incorrect responses had a sensitivity of 33% and specificity of 87.6%. CONCLUSION: VBS testing was more sensitive and JPS testing was more specific in making a clinical diagnosis of DSP. For timed VBS, duration of >8 s at the great toe was a useful test to rule out DSP, and for JPS testing at the great toe, obtaining two or more incorrect responses was a useful test in ruling in the diagnosis of DSP.