Trend of recovery after simple decompression for treatment of ulnar neuropathy at the elbow.

Ulnar neuropathy at the elbow is the second most prevalent peripheral compressive neuropathy, after carpal tunnel syndrome.1 With an estimated annual incidence of 75,000 cases in the United States, the health care and societal burden of ulnar neuropathy at the elbow continues to grow.2 Similar to carpal tunnel syndrome, various stressors on the ulnar nerve result in pain, numbness, and weakness in ulnar neuropathy at the elbow. Although the biomechanics of the ulnar nerve as it traverses the elbow are different from those on the median nerve in the carpal tunnel, surgical treatments for carpal tunnel syndrome and ulnar neuropathy at the elbow are similar in aiming to relieve nerve compression.3,4 Traditionally, functional outcomes measures used in evaluating treatment for compressive neuropathies have included grip strength and two-point discrimination, among others. Studies using these measures for postoperative evaluation of carpal tunnel syndrome and ulnar neuropathy at the elbow found recovery to take many months, and over 1 year for some.5–8 However, using patient-rated questionnaires, patients report symptomatic improvement far earlier than functional testing indicates. Questionnaires such as the Michigan Hand Questionnaire; the Disabilities of the Arm, Shoulder and Hand questionnaire; and the disease-specific Carpal Tunnel Questionnaire have been validated for carpal tunnel syndrome and ulnar neuropathy at the elbow and are more responsive than the functional tests.9–13 Improvement in these patient-reported outcomes after carpal tunnel surgery occurs in 6 weeks or less.14 Controversy remains as to the optimal surgical treatment for ulnar neuropathy at the elbow; however, numerous prospective trials, systematic reviews, and meta-analyses have shown no difference in outcomes among the various surgical techniques.15–18 These studies advocate simple decompression as the less invasive and less costly procedure, with equivalent outcomes. In all of these trials, long-term outcomes were the main focus. No study has reported the timing of recovery after surgery for ulnar neuropathy at the elbow. Determining how patients recover after surgery is not only critical in understanding the pathophysiology of ulnar neuropathy at the elbow but can guide optimal treatment and management. In addition, it may facilitate establishing appropriate patient and provider expectations, which play a significant role in outcomes. The Surgery of the Ulnar Nerve Study Group, a collaboration of five centers, was established to further investigate this condition. Patients with ulnar neuropathy at the elbow were treated with simple decompression and evaluated at 6 weeks, 3 months, 6 months, and 1 year postoperatively. All three questionnaires—the Michigan Hand Questionnaire; the Carpal Tunnel Questionnaire; and the Disabilities of the Arm, Shoulder and Hand questionnaire—were administered and have been validated for ulnar neuropathy at the elbow by this group.19 Objective measures were also used. The timing of improvement in all of these metrics was evaluated in this cohort. We hypothesized that recovery after surgery for ulnar neuropathy at the elbow would take longer than reported for carpal tunnel syndrome but would occur earlier than previously believed.