[Neurological recovery after cervical cord decompression for canal stenosis myelopathy].

PURPOSE OF THE STUDY Progressive myelopathy secondary to stenosis of the spinal canal is generally treated by surgery. Results of surgical decompression are generally good but the pattern of neurological recovery has not been studied. We followed a cohort of patients who underwent cervical cord decompression to study the course of neurological recovery. MATERIAL AND METHODS The study cohort included 39 patients (22 men and 17 women), mean age 65.7 years who underwent surgery between 1998 and 2002 for progressive cervical myelopathy. The same surgeon performed all procedures (23 posterior and 16 anterior approaches). The JOA score and MRI findings were noted. The patients were seen at 1, 3, 6, 12, and 18 months then annually (JOA score). The Hirabayashi score was used to assess neurological recovery. Two populations were identified (group 1: preoperative JOA score > 6, group 2: preoperative JOA score<or=6). RESULTS The mean preoperative JOA score was 8.3/17, range 1-15. Ten patients had a severe JOA score (<6). The mean postoperative JOA score was 13.3 (range 3-17) at six months and remained stable during follow-up. Neurological recovery as assessed with the Hirabayashi technique was 52.5% on average at last follow-up. Neurological gain occurred mostly during the first to third month following decompression, remaining stable thereafter. Patients with a severe deficit exhibited the same recovery pattern but stabilized at a lower neurological level. Expressed in JOA points, neurological gain was very similar in the two groups. There was no significant difference between patients who under went anterior or posterior procedures. DISCUSSION AND CONCLUSION The pattern of neurological recovery in patients with degenerative cervical disease appears to be rapid during the first six months following surgical decompression. The level of recovery then levels off, irrespective of the severity of the initial deficit. This work demonstrated that more specific evaluation scales than the JOA score should be developed for assessment and follow-up of these patients.