Postoperative Walking Ability of Non-ambulatory Cervical Myelopathy Patients

Study Design. A retrospective analysis. Objective. The aim of this study was to clarify the postoperative improvement of walking ability and prognostic factors in nonambulatory patients with cervical myelopathy. Summary of Background Data. Many researchers have reported the surgical outcome in compressive cervical myelopathy. However, regarding severe gait disturbance,, it has not been clarified yet how much improvement can be expected. Methods. One hundred thirty-one nonambulatory patients with cervical myelopathy were treated surgically and followed for an average of 3 years. Walking ability was graded according to the lower-extremity function subscore (L/E subscore) in Japanese Orthopedic Association score. We divided patients based on preoperative L/E subscores: group A, L/E subscore of 1 point (71 patients); and group B, 0 or 0.5 point (60 patients). The postoperative walking ability was graded by L/E subscore: excellent, >= 2 points; good, 1.5 points; fair, 1 point; and poor, 0.5 or 0 points. We compared preoperative and postoperative scores. The cutoff value of disease duration providing excellent improvement was investigated. Results. Overall, 50 patients were graded as excellent (38.2%), and 21 patients were graded as good (16.0%). In group B, 17 patients (28.3%) were graded as excellent. Seventeen patients who were graded as excellent had shorter durations of myelopathic symptoms and/or gait disturbance (7.9 and 3.8 months respectively) than the others (29.5 and 8.9 months, respectively) (P<0.05). Receiver-operating characteristic curve showed that the optimal cutoff values of the duration of myelopathic symptoms and gait disturbance providing excellent improvement were 3 and 2 months, respectively. Conclusion. Even if the patients were nonambulatory, 28.3% of them became able to walk without support after operation. If a patient becomes nonambulatory within 3 months from the onset of myelopathy or 2 months from the onset of gait disturbance, surgical treatment should be performed immediately to raise the possibility to improve stable gait.