Translation and Validation of the Swedish Patient-Rated Ulnar Nerve Evaluation in Ulnar Nerve Entrapment

A Swedish version of the Patient-Rated Ulnar Nerve Evaluation (PRUNE-S), a patient-reported outcome measure for ulnar nerve entrapment, was created, according to cross-cultural adaptation guidelines, and reliability, validity, and responsiveness were evaluated.

In total, 43 patients (mean [SD] age, 49 [16] y; 54% men) were consecutively examined, including the PRUNE-S (retest: 23 patients; age, 48 [19] y; 61% men) with follow-up at 3 and 12 months after intervention. Patients with conservative intervention replied to a global rating of change question.

The PRUNE-S sum test-retest assessment showed high Cronbach alpha value (0.99) and agreement by intraclass correlation coefficient (0.98) with good limits of agreement (PRUNE-S sum between -14 and 14). An exploratory factorial analysis showed a different PRUNE-S subscale categorization (subscale ranges: Cronbach alpha, 0.87-0.98; intraclass correlation coefficient, 0.87-0.98). The subscales, except the sensory symptoms subscale, of the PRUNE-S and their sum (r = 0.87, P < 0.001) correlated strongly with Quick Disabilities of the Arm, Shoulder, and Hand questionnaire. Grip and pinch grip strength did not correlate with subscales or with PRUNE-S sum. Semmes-Weinstein monofilament score correlated moderately with sensory symptoms subscale (r = -0.45, P = 0.002). Global rating of change and difference in PRUNE-S sum revealed a moderate and strong association (3 months [n = 26]: r = -0.58, P = 0.002; 12 months [n = 12]: r = -0.84, P = 0.001, respectively).

Despite limitations in sample size, the PRUNE-S, with new subscale categorization, shows good to excellent psychometric properties with promising responsiveness and usefulness in clinical practice and research.