Most cited article - PubMed ID 20587498
Are subjects with spondylotic cervical cord encroachment at increased risk of cervical spinal cord injury after minor trauma?
Study DesignSingle-centre controlled pilot study.ObjectivesTo evaluate the effect of prophylactic surgery and to review the biases of a therapeutic trial in asymptomatic degenerative cervical cord compression (ADCC) patients.MethodsPatients with ADCC and at least 1 predictor of progression to symptomatic degenerative cervical cord myelopathy (DCM) were offered either prophylactic surgery or standard structured rehabilitation. Recruited patients were clinically followed to detect the development of symptomatic DCM.ResultsForty-one patients treated surgically and 68 patients treated non-surgically completed the minimum 36 months' follow-up; 3 recruited patients were lost from evaluation. The surgical group had a higher Neck Disability Index score and more severe MRI compression. A matched subgroup of 41 non-surgical patients was created to reduce potential bias. During the follow-up period we observed progression to symptomatic DCM in 1 surgical case (2.4%) compared to 9 patients in the non-surgical group (13.2%, P = 0.054) and 7 cases in the matched non-surgical group (17.1%, P = 0.029). We observed non-serious early postoperative complications in 4 patients, which resolved spontaneously or after surgical revision. In 9 patients with progression to DCM, the myelopathy was mild with mJOA scale 15-17. One patient in the non-surgical group and 1 patient in the surgical group who progressed to DCM underwent surgery with a good outcome.ConclusionsProphylactic surgery led to a significant decrease in proportion of ADCC patients with progression to DCM. The results justify the organisation of a large randomized multicentre trial that may demonstrate the benefit of prophylactic surgery in ADCC patients.
- Keywords
- asymptomatic degenerative cervical cord compression, degenerative cervical myelopathy, prophylactic surgery,
- Publication type
- Journal Article MeSH
Degenerative cervical myelopathy (DCM) represents the final consequence of a series of degenerative changes in the cervical spine, resulting in cervical spinal canal stenosis and mechanical stress on the cervical spinal cord. This process leads to subsequent pathophysiological processes in the spinal cord tissues. The primary mechanism of injury is degenerative compression of the cervical spinal cord, detectable by magnetic resonance imaging (MRI), serving as a hallmark for diagnosing DCM. However, the relative resilience of the cervical spinal cord to mechanical compression leads to clinical-radiological discordance, i.e., some individuals may exhibit MRI findings of DCC without the clinical signs and symptoms of myelopathy. This degenerative compression of the cervical spinal cord without clinical signs of myelopathy, potentially serving as a precursor to the development of DCM, remains a somewhat controversial topic. In this review article, we elaborate on and provide commentary on the terminology, epidemiology, natural course, diagnosis, predictive value, risks, and practical management of this condition-all of which are subjects of ongoing debate.
STUDY DESIGN: Narrative review. OBJECTIVES: To discuss the current understanding of the natural history of degenerative cervical myelopathy (DCM). METHODS: Literature review summarizing current evidence pertaining to the natural history and risk factors of DCM. RESULTS: DCM is a common condition in which progressive arthritic disease of the cervical spine leads to spinal cord compression resulting in a constellation of neurological symptoms, in particular upper extremity dysfunction and gait impairment. Anatomical factors including cord-canal mismatch, congenitally fused vertebrae and genetic factors may increase individuals' risk for DCM development. Non-myelopathic spinal cord compression (NMSCC) is a common phenomenon with a prevalence of 24.2% in the healthy population, and 35.3% among individuals >60 years of age. Clinical radiculopathy and/or electrophysiological signs of cervical cord dysfunction appear to be risk factors for myelopathy development. Radiological progression of incidental Ossification of the Posterior Longitudinal Ligament (OPLL) is estimated at 18.3% over 81-months and development of myelopathy ranges between 0-61.5% (follow-up ranging from 40 to 124 months between studies) among studies. In patients with symptomatic DCM undergoing non-operative treatment, 20-62% will experience neurological deterioration within 3-6 years. CONCLUSION: Current estimates surrounding the natural history of DCM, particularly those individuals with mild or minimal impairment, lack precision. Clear predictors of clinical deterioration for those treated with non-operative care are yet to be identified. Future studies are needed on this topic to help improve treatment counseling and clinical prognostication.
Impaired gait is one of the cardinal symptoms of degenerative cervical myelopathy (DCM) and frequently its initial presentation. Quantitative gait analysis is therefore a promising objective tool in the disclosure of early cervical cord impairment in patients with degenerative cervical compression. The aim of this cross-sectional observational cohort study was to verify whether an objective and easily-used walk and run test is capable of detecting early gait impairment in a practical proportion of non-myelopathic degenerative cervical cord compression (NMDCC) patients and of revealing any correlation with severity of disability in DCM. The study group consisted of 45 DCM patients (median age 58 years), 126 NMDCC subjects (59 years), and 100 healthy controls (HC) (55.5 years), all of whom performed a standardized 10-m walk and run test. Walking/running time/velocity, number of steps and cadence of walking/running were recorded; analysis disclosed abnormalities in 66.7% of NMDCC subjects. The DCM group exhibited significantly more pronounced abnormalities in all walk/run parameters when compared with the NMDCC group. These were apparent in 84.4% of the DCM group and correlated closely with disability as quantified by the modified Japanese Orthopaedic Association scale. A standardized 10-m walk/run test has the capacity to disclose locomotion abnormalities in NMDCC subjects who lack other clear myelopathic signs and may provide a means of classifying DCM patients according to their degree of disability.
