Neuritis ossificans of the common peroneal nerve

Abstract

Dear Sir: We read with interest the 2009 report by Trigkilidas et al. of an unusual case of neuritis ossificans of the common peroneal nerve treated at the historic Royal National Orthopaedic Hospital in Stanmore, UK [1]. The term “neuritis ossificans” was originally introduced by our group in 1999 [2, 3]. At least, that is what we thought at the time. The designation harked back to its striking histological similarities with heterotopic ossification and myositis ossificans, processes often associated with trauma, but occurring within nerve. Histologically similar cases had previously been published under various designations. More recent cases of so-called neuritis ossificans have been reported by others, as have been summarized by Trigkilidas [1]. However, we were recently surprised to find that the term neuritis ossificans had been introduced long ago [4]— at our very own institution, no less. It was ascribed to an entirely different lesion, one with a dire prognosis. Herein, we seek to clarify the literature with respect to the term neuritis ossificans—its history, current usage, and clinical significance. The original patient in whom the term had been applied was a 29-year-old woman who presented to Mayo Clinic in the winter of 1939. Her case was reported in 1946 by the esteemed neurologist Henry Woltman and the neurosurgeon Alfred Adson [4]. The initial clinical diagnosis was that of post-traumatic neuritis or plexitis affecting the posterior cord of the left brachial plexus. A 3-year period of incomplete improvement and stabilization followed, but her neurological status worsened over the next 4 years. Upon presentation in 1946 she had developed complete loss of left brachial plexus function and a Brown–Sequard syndrome. The radiographic findings were illustrated in the published paper and showed a large, calcified soft tissue mass in the supraclavicular region and lower cervical spine. Its appearance was suggestive of myositis ossificans. She underwent a two-stage operative procedure, the first being a cervical and upper thoracic hemilaminectomy that revealed an intraand extradural mass that extended through the left C5–C6 foramen. The spinal cord was decompressed. In the first operative note of 30 May 1946, Adson wrote: