In patients with cervical myelopathy, nonoperative management is most likely to be successful when there is a larger transverse area of the spinal cord.
In patients with physical exam findings and symptoms of cervical myelopathy, surgical treatment is usually indicated. There may be a subset of patients with mild symptoms that do better with nonoperative treatment, although the specific indications for nonoperative treatment remains controversial. The Japanese Orthopaedic Association (JOA) classification system is frequently used to measure the severity of symptoms. It is a 17 point scoring system based on: 1) upper extremity function, 2) lower extremity function 3) sensory function 4) bladder function. A score of 17 is normal.
Kadanka et al. compared conservative and surgical treatment of spondylotic cervical myelopathy. They found patients who had good outcomes with conservative treatment were older in age, had normal central motor conduction time (CMCT), and had a larger transverse area of the spinal cord (>70mm2).
Rao et al. report surgical treatment is indicated for most patients with clinically evident cervical spondylotic myelopathy. They state patients with very early or mild clinical findings should be clinically and radiographically assessed with regard to their level of disability, the duration of symptoms, the degree of stenosis, and evidence of progression. A decision regarding treatment is made by weighing these factors against the risks of operative treatment.
Wada et al. looked at the long term outcomes of surgical treatment and the association with the JOA score. They recommend operative treatment when there is a JOA score of <13 points and spinal cord compression on imaging studies.
Illustration A is a table showing the JOA classification and scoring system. Illustration B shows the different radiographic measurements Rao et al. recommend to evaluate cervical myelopathy.
Answer 1: Increased central motor conduction time (CMCT) would be a poor prognostic indicator for nonoperative treatment.
Answer 3: Isolated low intramedullary signal on T1WI are thought to represent cord edema or irreversible changes such as gliosis or microcavitation and are likely to show little improvement with conservative OR surgical interventions.
Answer 4: Per the discussion above, a midsagittal diameter of the spinal canal of <13mm would be a poor prognostic indicator for nonoperative treatment.
Answer 5: According to Kadanka et al, older patients do better with nonoperative management.
Kadanka Z, Mares M, Bednarík J, Smrcka V, Krbec M, Chaloupka R, Dusek L. Predictive factors for spondylotic cervical myelopathy treated conservatively or surgically. Eur J Neurol. 2005 Jan;12(1):55-63.
PMID:15613148 (Link to Abstract)
Rao RD, Gourab K, David KS. Operative treatment of cervical spondylotic myelopathy. J Bone Joint Surg Am. 2006 Jul;88(7):1619-40.
PMID:16818991 (Link to Abstract)
Wada E, Suzuki S, Kanazawa A, Matsuoka T, Miyamoto S, Yonenobu K. Subtotal corpectomy versus laminoplasty for multilevel cervical spondylotic myelopathy: a long-term follow-up study over 10 years. Spine (Phila Pa 1976). 2001 Jul 1;26(13):1443-7; discussion 1448. PubMed PMID: 11458148.
PMID:11458148 (Link to Abstract)