Incidence of Nerve Injury After Extremity Trauma in the United States

Abstract

Background: Traumatic peripheral nerve injuries cause chronic pain, disability, and long-term reductions in quality of life. However, their incidence after extremity trauma remains poorly understood.

Methods: The IBM® MarketScan® Commercial Database from 2010 to 2015 was used to identify patients aged 18 to 64 who presented to emergency departments for upper and/or lower extremity traumas. Cumulative incidences were calculated for nerve injuries diagnosed within 2 years of trauma. Cox regression models were developed to evaluate the associations between upper extremity nerve injury and chronic pain, disability, and use of physical therapy or occupational therapy.

Results: The final cohort consisted of 1 230 362 patients with employer-sponsored health plans. Nerve injuries were diagnosed in 2.6% of upper extremity trauma patients and 1.2% of lower extremity trauma patients. Only 9% and 38% of nerve injuries were diagnosed by the time of emergency department and hospital discharge, respectively. Patients with nerve injuries were more likely to be diagnosed with chronic pain (hazard ratio [HR]: 5.9, 95% confidence interval [CI], 4.3-8.2), use physical therapy services (HR: 10.7, 95% CI, 8.8-13.1), and use occupational therapy services (HR: 19.2, 95% CI, 15.4-24.0) more than 90 days after injury.

Conclusions: The incidence of nerve injury in this national cohort was higher than previously reported. A minority of injuries were diagnosed by emergency department or hospital discharge. These findings may improve practitioner awareness and inform public health interventions for injury prevention.

Keywords: administrative database; diagnosis; epidemiology; incidence; nerve; nerve injury; outcomes; research & health outcomes; specialty; surgery.

Figure 1.

Cumulative incidence curves for peripheral nerve injury diagnoses. (a) Cumulative incidences of upper extremity nerve injury diagnoses within 2 years of upper extremity trauma. (b) Cumulative incidence of lower extremity nerve injury diagnoses within 2 years of lower extremity trauma.

Figure 2.

Among patients with known mechanisms of traumatic injury (E-codes), proportions of upper extremity nerve injuries that were associated with 7 common mechanisms. Note. MVA represents motorized vehicle accidents. Fifty percent of ulnar nerve injuries (dark blue, cross pattern) were associated with falls. In comparison, falls were experienced by 29% of patients who were not diagnosed with any upper extremity nerve injury (light gray, thin diagonal pattern).