Closing–opening wedge osteotomy for severe, rigid, thoracolumbar post-tubercular kyphosis

Abstract

Childhood spinal tuberculosis, especially when associated with severe vertebral destruction of more than two vertebral bodies can end up in severe deformity. These children show progressive deformity throughout the period of growth and can develop severe kyphosis of >100°. Such kyphosis is severely disabling with significant risk of neurological deficit and respiratory compromise. Surgical correction of these deformities by both anterior and posterior approaches has been described but each have serious limitations of approach, correctability and safety. We describe here a technique of posterior closing-anterior opening osteotomy, which allowed us to correct a rigid post-tubercular deformity of 118° in a 13-year-old boy with neglected spinal tuberculosis. The patient was a 13-year-old boy, who had contracted spinal tuberculosis at the age of 6 years. Although the disease was cured by anti-tubercular chemotherapy, he continued to deteriorate in deformity and presented to us with severe thoracolumbar kyphosis (118°). He was neurologically intact but was beginning to show shortness of breath on exertion. Patient also had fore shortening of the trunk with impingement of the rib cage on the iliac crest. Radiographs revealed complete destruction of T12, L1 and L2 vertebral bodies with the T11 vertebra fusing with L3 anteriorly. CT scans and MRI revealed severe collapse of the vertebral column and the spinal cord being stretched over the 'internal gibbus', which was formed by the remnants of the destroyed vertebrae. A single stage closing-opening osteotomy was done by a midline posterior approach with continuous intraoperative spinal cord monitoring. The procedure involved extensive laminectomy of T11-L2, pedicle screw fixation of three levels above and three levels below the apex, a wedge osteotomy at the apex of the deformity from both sides, anterior column reconstruction by appropriate-sized titanium cage and gradual correction of deformity by closing the posterior column using the cage as a fulcrum. This allowed us to achieve a correction to 38° (68% correction). There was no intraoperative or perioperative adverse event and patient had good functional and radiological outcome at 1-year follow-up. In this Grand Rounds case presentation, we have also discussed the aetiology and evolution of severe post-tubercular kyphosis, which is the most common cause of spinal deformity in the developing world. Early identification of children at risk for severe deformity, the time and ideal methods of prevention of such deformities are discussed. The pros and cons of the available options of surgical correction of established deformity and the merits of our surgical technique are discussed.