A Novel Surgical Criteria for Degenerative Cervical Myelopathy in Chinese Ethnicity

Degenerative Cervical Myelopathy (DCM) is an age-related irreversible degenerative disease predominantly affecting the elderly aged 50 and over. DCM is usually triggered by ossification of the posterior longitudinal ligament or ossification of ligamentum flavum or prolapsed intervertebral disc over the cervical spine. Specific clinical signs characterized the presence of cervical spinal cord compression; including Hoffmann's sign, Finger Escape Sign, Scapulohumeral Reflex, and Reverse Supinator Reflex. Hand numbness, clumsiness, and gait disturbance. These are featured clinical manifestations and well-known indicators for detailed clinical and radiographic investigation, such as Magnetic Resonance Imaging (MRI) for diagnosis and surgical planning.

Surgical intervention is considered to be the most effective treatment for DCM worldwide. It is the only evidence-based treatment to halt disease progression and allow modest improvement in function and quality of life. DCM progression is not specific to predict the timing for surgery, though it is still debated. Length of symptoms, pre-operative Modified Japanese Orthopaedic Association Scoring System for Cervical Myelopathy (mJOA) and physical performance are suggested as recovery predictors in DCM.

In current practice, the offer of surgical treatment is entirely based on the combination of the evidence of cord compression in Magnetic Resonance Imaging (MRI) and mJOA. DCM who are at risk of critical neurological deficits have a reduced anteroposterior diameter of the spinal canal less than 9 mm or cross-sectional area of the spinal cord less than 40 sq. mm; mJOA less than 13 with evidence of functional deterioration will be offered with surgical intervention. MRI and mJOA are used as the golden standard for the indication of surgical intervention in the aspect of radiological deformities and self- perceived functional deficits. The concern on the clinical predictor, the physical performance, was overlooked and lacked a compromised criterion in the physical performance tests for surgical decisions. Therefore, this study aims to develop DCM-specific criteria from physical performance tests in predicting the surgical indication for DCM in the Chinese population.