Posterior/Anterior/Posterior Sequence in Reconstructive Spinal Surgery

· (c – DePuy AcroMed)
Miami, Florida, USA

Purpose: Patients requiring complex spinal reconstruction have two common factors, global kyphosis and anterior- posterior rigidity. This study investigates the efficacy and safety of a three stage same day surgery for deformity correction. The procedure consists of posterior wide release or osteotomy, spinal anchor placement, graft harvesting: second stage is anterior multilevel interbody structural graft and fusion: third stage is posterior placement of rods.

Methods: This is a prospective study of patients with this procedure between Jan, 1994 and Jan, 2000. Multiple parameters were measured. Outcome evaluation was by SF 36. 80 consecutive patients are the study group, with 78 available for the two year minimum follow-up.

Results: 35 had previous surgery (27 lumbar flat back, 3 pseudoarthroses, 5 imbalance). 45 had no previous surgery (18 degenerative scoliosis, 22 adult idiopathic scoliosis, 5 complicated adolescent deformity). Follow-up averaged 38 months (26- 60). Mean age was 52 (13-77). No procedure was abandoned once initiated. Blood loss averaged 1500cc, operative time 7.2 hrs. Previous surgery: All had multiple level Smith-Peterson osteotomy, posterior spinal anchor placement, anterior discectomy, distraction, and structural graft placement, usually L-2 to sacrum, and rod placement at third stage. In flat back, lordosis increased from 2° to 23° in the flat segment. Coronal imbalance, when present, improved from 8.5cm to 0.5cm. No previous surgery: Three stage surgery was employed in all. Adult idiopathic curves, mostly lumbar, averaged 77°, improved to 24° (70%) at two years. The fractional lumbosacral curve improved from 34° to 12°, and the thoracic from 68° to 24°. Correction loss ranged from 0-18° (mean 3°).The upper lumbar kyphotic segment was improved from +18° to a lordotic -22°. The total lordosis was never <33°. The de novo group had the same sequence, with the posterior portion from T-11 to sacrum, anterior L-2 to sacrum. The main lumbar curve improved from 34 to 5°. Lordosis improved from -5 to -33°.

Complications: Major complications: 1 death from embolism, 2 psuedoarthrosis with revision, 1 coronal imbalance with revision, and 1 prolonged ventilation, total 6.25%. Minor complications were usual. Outcomes: Per SF37, 86% were satisfied, 90% would do it again.

Discussion: Severe rigid deformities are a challenge.Three stage same day surgery achieves maximum mobility and correction. Excellent correction and acceptable complication rate was reliably achieved.

· If noted, the author indicates something of value received. The codes are identified as: a-research or institutional support; b-miscellaneous funding; c-royalties; d-stock options.