OUTCOME OF COMBINED ANTERIOR – POSTERIOR ARTHRODESIS FOR PAINFUL ADULT LUMBAR AND THORACO–LUMBAR SCOLIOSIS

Vedat Deviren, M.D.,
Arash Emami. M.D.,
Jason A. Smith, M.D.,
Sigurd Berven, M.D.,
Serena S. Hu M.D.,
David S. Bradford, M.D.

INTRODUCTION:
Painful adult lumbar and thoracolumbar scoliosis often requires a combined anterior posterior fusion to L4, L5 or the sacrum in order to correct rigid deformity, maintain lumbar lordosis, and improve fusion rate. This is a retrospective study to investigate the outcome and complication rate of combined anterior–posterior arthrodesis to L4 vs L5 vs Sacrum in patients with painful adult lumbar and thoracolumbar scoliosis.

METHODS:
Forty consecutive adult patients with lumbar or thoracolumbar scoliosis who had undergone a primary combined anterior and posterior fusion from the upper thoracic spine to L4 (12), L5 (6) or to the Sacrum (22), with an average age of 53 years (25–78), and a minimum follow–up of two years were included in this study. All patients reported low back pain, buttock or leg pain. The distal vertebra to be fused was determined based on fixed deformity or severe degenerative changes. Outcome data was obtained by using the modified SRS outcome instrument.

RESULTS:
There was a higher rate of peri–operative complications in patients with fusions to the sacrum than to L4 or L5. For fusion to the sacrum, there were 11 minor complications and 6 major complications in 9 patients, a 40% perioperative complication rate. Patients with fusion to L5 had 33% peri–operative complication rate. Patients with fusion to L4 had a 25% peri–operative complication rate. All complications were appropriately managed with no long term sequelae. Long term complication rate (pseudoarthrosis, revision, etc.) was also higher in patients with fusion to the sacrum. The average structural curve correction was 55% for the entire group, with no statistical difference among the three groups. Lumbar lordosis improved in all patients by an average of 11 degrees. Modified SRS outcome instrument score for fusion to the sacrum (73% ) was less than for fusion to L5 (79%) and to L4 (89%). Patients with fusions to sacrum scored lower in all categories than fusions to L5 or L4. Based on returned questionnaires, 91% of patients were satisfied with their surgical outcome (4.52 out of 5). All patients who had been fused to the L4 and L5 were satisfied, One patient was not satisfied, and two patients were neither satisfied nor dissatisfied.

DISCUSSION:
Patients with fusion to the sacrum had a higher complication rate and a lower outcome score. Despite a high complication rate, 91% of our patients were satisfied with their overall outcome and would have the same management again. In conclusion, a combined anterior and posterior arthrodesis for painful adult lumbar and thoracolumbar spinal scoliosis provides predictable correction of deformity, excellent pain relief, and an extremely high patient satisfaction rate in patients for whom this extensive surgery is indicated.