Diabetes Mellitus (DM) is the most common serious metabolic disorder having substantial peripheral nervous system (PNS) complications. Involvement of the autonomic nervous system and the PNS represents one of the four major complications of DM, along with retinopathy, nephropathy, and vascular disease.

DM makes nerves vulnerable for minor repetitive trauma, and carpal tunnel syndrome (CTS) is reported as more common in diabetic individuals.

The purposes of this study were to correlate CTS with diabetic polyneuropathy (DMPN), to evaluate sensitivity and specificity for diagnostic criterias of CTS and to correlate with the changes in respect to age, duration, and various blood components such as glucose, blood urea nitrogen (BUN), creatinine, glycosylated hemoglobin (HBA1C) in CTS of DM. We assessed 150 DM patients (male 74, female 76) for DMPN and CTS. The parameters of diagnostic criteria in CTS were as follows: median-ulnar motor latency difference, ratio of wrist-palm sensory latency, median sensory latency across the wrist, median-ulnar sensory difference to ring finger, and median-radial sensory difference to thumb. And we also attempted DMPN with CTS in according to age, duration, blood glucose, BUN, creatinine, and HbA1C.

The results are as follows:

1) There is a significantly higher incidence of CTS in diabetic patients with DMPN (51.8%) than those without DMPN (34.3%).

2) Median sensory latency across the wrist shows the greatest sensitivity (98%) in the diagnosis of CTS in DM.

3) Median-ulnar motor latency difference shows the greatest specificity (100%) in the diagnosis of CTS in DM.

4) There are no significant differences in age, duration, blood glucose, BUN/Cr, and HbA1C between the patients of DM with CTS and those without CTS.

In conclusion, we recommend regular electroneurophysiologic examination for CTS in patients with DMPN by evaluation of median sensory latency across the wrist with median-ulnar motor latency difference.

Keywords :Diabetes mellitus, Polyneuropathy, Carpal tunnel syndrome