To identify radiological patterns of compression (POC) of the spinal cord To develop a surgical protocol based on POC and determine its efficacy. To identify parameters predicting outcome of surgery
Pattern I – predominant one/two level compression in normal/narrow canal Pattern II – anterior &
posterior compression at one/ two levels (pincer cord) Pattern III – Three or more levels of predominant anterior compression with a normal canal Pattern III(A) – Pattern III in a patient with multiple medical co-morbidities Pattern IV – Three/more levels of anterior compression in narrow canal +/− posterior compression (beaded cord) Pattern IV(A) – Pattern IV with one/two level severe compression amongst the multiple anterior compressions. Mean follow-up was 3 yrs (2–8). ACDF was performed for patterns I, II &
III and posterior decompression for pattern IV and III(A). For pattern IV(A), a two stage primary posterior decompression followed by targeted ACDF at the site of maximal compression was performed. The clinical outcome was measured by modified JOA (mJOA) score, Hirayabashi Recovery Rate (HRR) and functional outcome by modified Neck Disability Index (NDI).
Rigid angular kyphotic deformities of the spine have been corrected by staged anterior and posterior procedures. This paper evaluates the efficacy of single stage transpedicular decancellation, vertebral column mobilization and spinal shortening in the correction of rigid THORACIC kyphotic deformities in adolescent patients. Between 1993 and 1999, 21 patients with rigid kyphosis underwent deformity correction using the above procedure. The deformity was thoracic in 6 patients, thoraco-lumbar in 14 and lumbar in one patient. This report focuses on 6 patients with thoracic deformity. The etiology in 5 patients was due to tuberculosis while one patient had a congenital anomaly. There were 4 females and 2 male patients. The average age was 12 years. The average kyphosis was 75 degrees (38 – 135 degrees). Of the 6 patients, 2 had preoperative paraplegia. All cases were assessed using CT and MRI scans in addition to plain radiographs. The surgical technique utilized the principle of transpedicular decancellation through a single posterior midline exposure in the prone position. Following complete decancellation of the apical vertebrae, the proximal and distal vertebral column was adequately mobilized to enable spinal shortening along with anterior translation. Segmental spinal instrumentation was used to achieve stable fixation.Intraoperatively, the wake-up test was used to assess the neurological function. This was followed by anterior interbody fusion and posterolateral fusion. At an average follow-up of 36 months, average kyphosis correction was 61% and all cases were adequately fused. Both cases with paraplegia recovered completely. The average loss of correction was 6 degrees. One patient developed hyperlordosis below the corrected level. This was revised by extending the spinal fixation to include the lower levels. In conclusion, the above procedure is used as a last resort for correction of rigid angular deformities. It is a safe but demanding procedure. Spinal column shortening is essential to avoid neurologic compromise and balance the column.
Craniovertebral tuberculosis accounts for 5% of all cases of tuberculosis and is the commonest infective pathology affecting this region. There are very few published reports discussing the presentation and management of this complex pathology. 30 cases of craniovertrebral tuberculosis treated between 1989–97 were reviewed retrospectively. The average age was 24 years (range 6 – 42 years) with a follow up of 41 months (range 36 – 48 months). Two main groups on the basis of atlantoaxial stability. 18 (60%) had an unstable atlantoaxial articulation and of these 12 (66%) had a fully reducible AAD in extension. 17 patients (56%) had varying degrees of neurological deficit with lower limb spasticity being the commonest. Antituberculous chemotherapy, skeletal traction in extension and prolonged bracing with moulded philadelphia collar were main stays of conservative treatment. Surgery in the form of posterior occipito cervical arthrodesis was needed in 13 patients (43%) and indications included incompletely reduced AAD, non resolving neurological deficit and persistent instability despite 6 weeks in traction. There was 93% success rate with resolution of infection (range 4 – 8 months) and improvement in neurological deficit 2 patients had incomplete neurological recovery and required 2nd stage anterior transoral odontoidectomy. Management strategies based on the presence or absence of instability and neurological deficit can give a very satisfactory outcome with judicious combination of drug therapy, bracing and surgical decompression with fusion.