Cubital Tunnel Syndrome: Incidence and Demographics in a National Administrative Database

BACKGROUND: Compressive neuropathy of the ulnar nerve at the elbow, or cubital tunnel syndrome (CuTS), is the second most common entrapment neuropathy of the upper extremity after carpal tunnel syndrome. While several studies have reported risk factors and outcomes for select populations (mostly surgical), it is difficult to interpret these data without an accurate measure of CuTS disease burden in the general population. OBJECTIVE: To estimate the incidence of CuTS among US health plan enrollees, using a large administrative health care claims database comprised of individuals from all 50 states. METHODS: An administrative database of commercial insurance beneficiarieswas queried for diagnosis and treatment of CuTS over a 6-yr period. We examined subsequent claims to determine frequency of subsequent surgical treatment. Descriptive statistics were used to determine the association of incident cases and surgical treatment with age and gender. RESULTS: The estimated adjusted incidence rate of CuTS is 30.0 per 100 000 person-years. Of the 53 401 identified new cases within this cohort from 2006 to 2012, 41.3% were treated surgically. Incident cases were identified more frequently in men than in women (31.2 vs 28.8 cases per 100 000 person-years), though we observed more cases in women than in men below 50 yr of age (20.9 vs 19.5 cases per 100 000 person-years). Overall, incident cases increase with age in both men and women. In addition to incident cases being more common with increasing age, the percentage of cases treated surgically also increases with age (surgery in 34.4% of cases in the 18-30 yr group vs 48.8% of cases in the 60-65 yr group). CONCLUSION: The purpose of this study was to estimate the incidence of CuTS among US health plan enrollees. This is the largest published study on the incidence of CuTS, and the first to look at a US population. The overall adjusted incidence of CuTS was 30.0 per 100 000 person-years. Of patients who developed CuTS, 41.3% were treated surgically during the study period. Our results corroborate previously reported literature suggesting incidence increases significantly with age, with a slightly higher incidence in males. A high percentage of people who were diagnosed with CuTS and ended up receiving surgical intervention (41.3%) were older males. These results may aid practitioners in providing some basic prognostic information to patients who develop CuTS.