Utility of 'baseline' electrodiagnostic studies for carpal tunnel release

The utility of routine preoperative electrodiagnostic studies for carpal tunnel syndrome is controversial. One argument in support of routine preoperative electrodiagnostic study is the acquisition of an objective baseline for comparison in cases of postoperative symptom persistence or recurrence. We identified 1141 patients who underwent carpal tunnel release in 1383 limbs at a tertiary care referral centre from July 2008 to June 2013. The prevalence of preoperative electrodiagnostic study acquisition was 88%. Postoperative studies were acquired in 129 out of 1383 limbs that underwent carpal tunnel release (9.3%) at a median 24.3 months after surgery. Assessment of the median nerve for persistent or recurrent carpal tunnel syndrome was part of the rationale for obtaining electrodiagnostic studies in 81% of cases in which postoperative electrodiagnostic studies were acquired. Younger age, lower body mass index, Hispanic race and education level of eighth grade or less were associated with postoperative electrodiagnostic study acquisition. Level of evidence: IV.