An Outcome Study for Ulnar Neuropathy at the Elbow: A Multicenter Study by the Surgery for Ulnar Nerve (SUN) Study Group

BACKGROUND: Many instruments have been developed to measure upper extremity disability, but few have been applied to ulnar neuropathy at the elbow (UNE). OBJECTIVE: We measured patient outcomes following ulnar nerve decompression to (1) identify the most appropriate outcomes tools for UNE and (2) to describe outcomes following ulnar nerve decompression. METHODS: Thirty-nine patients from 5 centers were followed prospectively after nerve decompression. Outcomes were measured preoperatively and at 6 weeks, 3 months, 6 months, and 12 months postoperatively. Each patient completed the Michigan Hand Questionnaire (MHQ), Carpal Tunnel Questionnaire (CTQ), and Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaires. Grip, key-pinch strength, Semmes-Weinstein monofilament, and 2-point discrimination were measured. Construct validity was calculated by using Spearman correlation coefficients between questionnaire scores and physical and sensory measures. Responsiveness was assessed by standardized response means. RESULTS: Key-pinch (P = .008) and Semmes-Weinstein monofilament testing of the ulnar ring (P < .001) and small finger (radial: P = .004; ulnar: P < .001) improved following decompression. Two-point discrimination improved significantly across the radial (P = .009) and ulnar (P = .007) small finger. Improved symptoms and function were noted by the CTQ (preoperative CTQ symptom score 2.73 vs 1.90 postoperatively, P < .001), DASH (P < .001), and MHQ: function (P < .001), activities of daily living (P = .003), work (P = .006), pain (P < .001), and satisfaction (P < .001). All surveys demonstrated strong construct validity, defined by correlation with functional outcomes, but MHQ and CTQ symptom instruments demonstrated the highest responsiveness. CONCLUSION: Patient-reported outcomes improve following ulnar nerve decompression, including pain, function, and satisfaction. The MHQ and CTQ are more responsive than the DASH for isolated UNE treated with decompression.