Comparative Responsiveness of the Michigan Hand Outcomes Questionnaire and the Carpal Tunnel Questionnaire After Carpal Tunnel Release

Abstract

The literature supports self-administered questionnaire assessment tools for the measurement of outcome after surgical treatment of carpal tunnel syndrome (CTS). Traditional physical measures are less sensitive to clinical changes following carpal tunnel release (CTR) than fully validated designed outcome questionnaires. A number of validated outcome instruments have been compared to determine which is optimal with regard to sensitivity and responsiveness following surgery. To our knowledge, the Michigan Hand Outcomes Questionnaire (MHQ) and the Carpal Tunnel Questionnaire (CTQ) have not been compared in regard to their responsiveness and sensitivity to change following CTR. The aim of this prospective study was to compare the responsiveness of these 2 instruments when evaluating outcomes after CTR. Seventy-eight patients diagnosed with CTS and scheduled for unilateral open CTR were recruited and informed consent was obtained after ethics approval. Inclusion criteria were primary procedure, history, clinical signs, and conduction studies consistent with CTS. The MHQ and CTQ were both completed by each patient preoperatively and 6 months postoperatively. Results for all domains of the MHQ and all domains of the CTQ showed significant postoperative improvement. The overall responsiveness of both MHQ and CTQ were large (standardized response mean >or=0.8), however the CTQ demonstrated increased sensitivity to change after CTR compared to the MHQ. Although the standardized response mean (SRM) of the MHQ was 0.8, the SRM of the CTQ was 1.22. Both domains of the CTQ had an SRM well above 0.8, whereas half of the MHQ domains had an SRM below 0.8. The CTQ has demonstrated a greater responsiveness to clinical change following CTR than the MHQ. Therefore, the CTQ is a more sensitive instrument and researchers in the field of CTS should bear these findings in mind when choosing an outcome instrument for future studies. Diagnostic I.