Peripheral Nerve Injury Associated with a Subdermal Contraceptive Implant: Illustrative Cases and Systematic Review of Literature.

BACKGROUND

Despite demonstrable safety and efficacy of subdermal contraceptive implants (SCIs), both insertion and removal of SCIs in the arm have been associated with neurovascular complications. The aim of this study was to investigate type and prognosis of nerve injuries associated with SCIs.

METHODS

We performed a comprehensive search of 4 electronic databases for studies pertaining to patients with nerve injury and concurrent SCI. Studies published between January 1987 and June 2017 were included. Implant location, damaged nerves, clinical presentation, preoperative imaging (x-ray, ultrasound, magnetic resonance imaging), neurologic evaluation (nerve conduction studies, electromyography), and treatment methods were reviewed. To outline management strategies, 2 illustrative cases of major nerve injury caused by SCI removal were presented.

RESULTS

We analyzed 10 studies including 12 patients. Fourteen nerve injuries in 12 patients were reported during SCI insertion (n = 1) and removal (n = 11). Medial antebrachial cutaneous (n = 5) and median (n = 5) nerves were primarily affected. Neuropathic pain was the main symptom. Primary reasons for nerve injury were pulling or grasping of the nerve (n = 9) after mistaking it for the implant. Neurapraxia (n = 7) was the most common lesion and was treated with implant removal and clinical surveillance (n = 6). Five patients completely recovered; the remaining patients continued to have motor and/or sensory deficit at mean follow-up of 0.7 year (range, 0-2 years).

CONCLUSIONS

Nerve injuries related to SCIs are rare but potentially serious. For nonpalpable SCIs, a multidisciplinary approach, including practitioners with experience treating peripheral nerve injuries, is invaluable.