Risk factors for the development of degenerative cervical myelopathy: a review of the literature

Degenerative cervical myelopathy (DCM) encompasses various pathological conditions causing spinal cord (SC) impairment, including spondylosis (multiple level degeneration), degenerative disc disease (DDD), ossification of the posterior longitudinal ligament (OPLL), and ossification of the ligamentum flavum (OLF). It is considered the most common cause of SC dysfunction among the adult population. The degenerative phenomena of DDD, spondylosis, OPLL and OLF, is likely due to both inter-related and distinct factors. Age, cervical alignment, and range of motion, as well as congenital factors such as cervical cord-canal mismatch due to congenital stenosis, Klippel-Feil, Ehler-Danlos, and Down syndromes have been previously reported as potential factors of risk for DCM. The correlation between some comorbidities, such as rheumatoid arthritis and movement disorders (Parkinson disease and cervical dystonia) and DCM, has also been reported; however, the literature remains scare. Other patient-specific factors including smoking, participation in contact sports, regular heavy load carrying on the head, and occupation (e.g. astronauts) have also been suggested as potential risk of myelopathy development. Most of the identified DCM risk factors remain poorly studied however. Further researches will be necessary to strengthen the current knowledge on the subject, especially concerning physical labors in order to identify patients at risk and to develop an effective treatment strategy for preventing this increasing prevalent disorder.