Background:

Corticosteroid injections are commonly used in the treatment of carpal tunnel syndrome in adults. This study sought to determine success rates early on and at one year postoperatively of a single corticosteroid injection while identifying prognostic indicators for symptom recurrence and repeat intervention.

Methods:

Fifty-four consecutive wrists in forty-nine patients with carpal tunnel syndrome treated with a single corticosteroid injection were prospectively enrolled. Demographic data and information on comorbidities were identified with a study-specific questionnaire. The Boston Carpal Tunnel Questionnaire was administered prior to injection. Patients returned to clinic at six weeks and were contacted at three, six, nine, and twelve months post-injection to determine symptom and intervention status. Kaplan-Meier analysis and Cox regression modeling were used to estimate recurrence rates and to identify predictors of symptom recurrence and repeat intervention.

Results:

Fifty-four symptomatic wrists in forty-nine patients with a mean age of fifty-three years were included. Two patients (two wrists) were lost to follow-up. Patients reported symptom recurrence in thirty-one wrists at a median duration of 155 days post-injection. Nineteen wrists underwent carpal tunnel release at a median time of 181 days after the injection. No patient underwent a repeat injection. In our study, diabetic patients were at a 2.6-fold greater risk of reporting recurring symptoms within a one-year follow-up period. Survivorship free from symptom recurrence was 53% at six months and 31% at twelve months; survivorship from repeat intervention was 81% at six months and 66% at twelve months.

Conclusions:

A single injection achieved symptom relief in 79% of patients at six weeks; these results were maintained in 31% of patients at twelve months. Diabetic patients were at higher risk of symptom recurrence.