Introduction: Cervical spondylotic myelopathy (CSM) is the leading cause of spinal cord related disability in the elderly. It results from degenerative narrowing of the spinal which causes spinal cord compression. This leads to gait instability, weakness, numbness and, or urinary dysfunction. There has been indirect data that implicates a genetic component to CSM. Such a finding may contribute to the variety in presentation and outcome in this patient population. The val66met polymorphism, a mutation in the BDNF gene, has been implicated in a number of brain and psychological conditions, and here we investigate its role in CSM.

Methods: Ten subjects diagnosed with CSM were enrolled in this prospective study. Baseline subjective clinical evaluation using mJOA, Nurick and SF-36 were collected. In addition each subject underwent objective testing with gait kinematic assessments as well as hand functioning using the Purdue Peg Board. Blood samples were analyzed for the BDNF Val66met mutation.

Results: The prevalence of the BDNF Val66met mutation in this study was 60% amongst CSM patients compared to 32% in the general population. Individuals with abnormal met allele had worse baseline mJOA, and Nurick scores. Moreover, baseline gait kinematics and hand functioning testing were worse compared to their wild type counterpart.

Conclusions: BDNF Val66met mutation has a higher prevalence in CSM compared to the general population. Those with BDNF mutation have a worse clinical presentation compared to the wild type counterpart. BDNF may play a role in the development and severity of cervical spondylotic myelopathy.

Patient Care: This study help to better understand the pathophysiology of CSM. Additionally the findings could help improve the management of these patients.

Learning Objectives: 1. BDNF polymorphism is more prevalent in CSM. 2. Patients with BDNF val66met mutation present with worse clinical presentation based on nurick and mJOA scores. 3. CSM patients with val66met mutation report worse functioning based on SF-36 questionaire compared to their wild-type counterpart. 4. CSM patients with val66met mutation have worse gait at presentation.

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