Comparison of Patient-Reported Outcome Instruments in the Preoperative Evaluation of Cubital Tunnel Syndrome

Abstract

Purpose

Patient-reported outcomes are used routinely to assess disease severity in patients with cubital tunnel syndrome (CuTS). This study aimed to compare the relationships of patient-reported outcomes with clinical examination, electrodiagnostic (EDX), and ultrasound (US) measures.

Methods

Twenty-four patients presenting to an academic center with symptoms consistent with isolated CuTS were prospectively enrolled. Clinical examination measures were collected, including grip strength, key pinch, 2-point discrimination, presence of Tinel sign, and elbow flexion test result. Patients underwent EDX evaluation, and US was used to measure the cross-sectional area of the ulnar nerve around the elbow. Patients completed 3 questionnaires: Patient-Rated Ulnar Nerve Evaluation (PRUNE), Patient-Reported Outcomes Measurement Information System (PROMIS), and Disabilities of the Arm, Shoulder, and Hand (DASH). Questionnaire scores and clinical examination measurements were stratified based on EDX and US status. Pearson’s correlations were used to assess the associations of questionnaire scores with objective measures.

Results

Significant correlation in PROMIS-Physical Function (PROMIS-PF), PROMIS-Pain Interference (PROMIS-PI), PROMIS-Depression (PROMIS-D), PROMIS-Upper Extremity (PROMIS-UE), and DASH scores were observed between EDX−positive and -negative groups, while no significant correlation was seen between US- positive and -negative groups. Two-point discrimination significantly correlated with PRUNE, PROMIS-PF, PROMIS-UE, and DASH scores. All patient-reported outcome measures significantly correlated with sensory amplitude. PROMIS-D weakly correlated with maximum ulnar nerve cross-sectional area. No significant correlations between patient-reported outcome measures and motor EDX outcomes were observed.

Conclusions

Patient-reported symptom severity is more closely associated with EDX diagnosis than US status. PROMIS-PF and DASH displayed stronger correlations to objective measures than other patient-reported outcome measures. Sensory amplitude was the strongest predictor of subjective symptom severity relative to other measures.

Type of study/level of evidence

Diagnostic II.