Conservative treatment for cervical spondylotic myelopathy: prediction of treatment effects by multivariate analysis

Background context: Many studies have suggested only slight effects of conservative treatment on cervical spondylotic myelopathy (CSM), whereas a few reports describe conservative treatment as being effective. This suggested the influence of various factors on treatment outcomes. Purpose: We investigated symptomatic changes after conservative treatment in patients based on a clear understanding of the effects and limitations of conservative treatment. Study design: We have encountered cases that showed symptomatic improvement with conservative treatment and became interested in the effectiveness of conservative treatment for CSM and whether other factors affect the results of conservative treatment. Patient sample: We have analyzed the results of conservative treatment for CSM in 69 cases, derived from a population of 101 CSM cases. Outcome measures: Symptoms at the time of the first examination were compared with those at the final examination, and the patients were classified into three groups showing improvement, no change or exacerbation. Methods: Improvement or exacerbation of the symptoms was used as dependent variables and the collected factors as independent variables, and logistic regression was performed on these variables. Results: Multivariate analysis showed significant correlation between clinical outcome and the disease duration and the presence of rigorous conservative treatment. Conclusions: Conservative treatment for CSM is considered to be effective if it is performed intensively in selected patients. In treating CSM, the therapeutic approach must be selected first in consideration of the patient's disease duration. Conservative treatment must be carried out intensively after sufficient explanation to the patients. Timely surgical intervention is considered to be important if the symptoms show no change or exacerbation with conservative treatment.