Prevalence of permanent vocal cord paralysis after anterior cervical decompression and fusion at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH)

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand in partial fulfilment of the requirements for the degree of Master of Medicine. Johannesburg, 2018.Background: Anterior Cervical Discectomy and Fusion (ACDF) is a successful procedure performed by Orthopaedic surgeons for various pathologies that affect the cervical spine. It is however not without complications. The commonest neurological complication is Recurrent Laryngeal Nerve (RLN) injury leading secondarily to permanent Vocal Cord Paralysis (VCP). Aims and Objectives: The aim of this study was to assess the prevalence of permanent VCP post-ACDF at our Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) spinal unit. To study objectives are: 1) To correlate demographic, pathological and peri-operative patient factors to post-operative hoarseness and vocal cord paralysis and 2) To establish an association between post-operative hoarseness and clinical laryngoscopic cord status. Study design: This is a retrospective with prospective recall. Methods: Patients who underwent the procedure of ACDF at CMJAH from January 2012 to June 2016 were recruited telephonically to participate voluntarily. Our research study specific questionnaire was administered to the patients who consented for the study together with a post-operative direct laryngoscopy, performed by the Ear-Nose-Throat (ENT) specialist to assess vocal cord function. Results: Only 23 patients presented for participation. Post-operative hoarseness was present in 5 cases (23%). The likelihood of which was higher in white women who had ACDF for a degenerative cause involving two or more vertebral levels. However, our study found none of the cases had vocal cord paralysis. Conclusion: Post-operative hoarseness is common after ACDF, affecting almost a quarter of those who undergo the procedure. A white woman undergoing ACDF for a degenerative cause affecting multiple cervical spine levels is at risk, especially if being operated on the left hand side of the neck with a transverse incision. Although hoarseness suggests VCP, the relationship between the two is not always one of cause and effect. The former can exist due to other causes unrelated.LG201