Evaluation of carpal tunnel release outcomes by the Japanese version of the carpal tunnel syndrome questionnaire compared to an electrophysiological severity grade.

Abstract

The outcome of carpal tunnel release (CTR) one year postoperatively was assessed by the Japanese version of Carpal tunnel syndrome questionnaire, CTSI-JSSH. Patients were further graded by the electrophysiological severity scale and the CTSI-JSSH scores were compared amongst the Stages before surgery and one-year postoperatively. This study included 247 hands and the mean age of the patients was 68 years (range:26-91). They completed the CTSI-JSSH consisting of the two subscales of the symptom scale (CTSI-JSSH-SS) and the functional scale (CTSI-JSSH-FS) both preoperatively and at the follow-up period of one year. The change of the scores of the CTSI-JSSH-SS, CTSI-JSSH-FS and total CTSI-JSSH were examined. Electrophysiological examination was performed before CTR and graded according to the electrophysiological severity scale as Stage 1-5. The scores of the CTSI-JSSH-SS, CTSI-JSSH-FS and total CTSI-JSSH were compared amongst Stage 1-5. All CTSI-JSSH-SS, CTSI-JSSH-FS and total CTSI-JSSH scores improved significantly one-year postoperatively. Also, the standardized response mean (SRM) and effect size (ES) showed large responsiveness, i.e. 1.36/1.43, 1.12/1.08 and 1.43/1.45 respectively. There was no significant difference in the score of the CTSI-JSSH-SS, CTSI-JSSH-FS and total CTSI-JSSH amongst any of the Stages preoperatively, while the scores in Stage 5 were significantly inferior to the ones in Stages 3 and 4 one-year postoperatively. The clinical outcomes of CTR were favorable by assessment of the CTSI-JSSH. We suggest the postoperative inferior scores in Stage 5 may be due to the potential axonal damage which could explain the disappearance of distal motor latency and sensory nerve conduction velocity in Stage 5.