Neurological recovery in patients of old healed tubercular rigid kyphosis with myelopathy treated with transpedicular decancellation osteotomy

Abstract

The purpose of the study was to find out if transpedicular decancellation osteotomy (TDO) is recommendable for neurological recovery in patients with myelopathy due to tubercular rigid kyphosis. We have analyzed the pattern of recovery seen after the surgery and also made an effort to correlate the neurological recovery with preoperative clinical and radiological features. The clinical parameters used were (1) ASIA impairment scale for motor and sensory function, (2) sphincter dysfunction score, (3) time duration from the onset of myelopathy till the date of surgery, and (4) SRS 30 outcomes questionnaire. Radiological parameters used were (1) Cobb's angle in standing/sitting radiographs, (2) levels of gibbus, (3) cord changes in sagittal T2 MRI images, and (4) percentage of cord compression. Assessment was done preoperatively and at 1month, 3months, 6months, 1year and at 2years postoperatively. Seventeen patients were included. The follow-up period was 2years. We had one patient in ASIA A, nine patients in ASIA C and seven patients in ASIA D. Four patients with ASIA C presented with mild sphincter disturbance (score 2) and one presented with severe disturbance (score 1). The ASIA A patient had complete retention (score 0). The ASIA impairment scale improved after surgery, with maximum improvement at 3months and improvement continuing up to 6months. 16 (94%) patients had improvement in lower limb function and 5 (83%) patients had improvement of sphincter function. 94% patients had neurological recovery after the operation. The neurological recovery reached a plateau at 6months with no significant improvement in the further follow-up. Preoperative MRI changes, cord compression and duration from onset of myelopathy to day of surgery were not predictive of the final neurological outcome after surgery. TDO gives good results in delayed onset neurological deficits in caries spine with rigid kyphosis. At least, one grade improvement in the neurological status of patients with ASIA C and ASIA D can be expected. Maximum improvement in the neurology is seen in the first 3months and up to 6months from the date of surgery, without much improvement thereafter. Level of evidence Level IV.