Long Fusion to the Sacrum in Adult Spinal Deformities: Outcome and Complications of Luque Galveston vs. Iliac Screws vs. Sacral Screws

Arash Emami, M.D.;
Vedat Deviren. M.D.;
Sigurd Berven, M.D.;
Jason A. Smith, M.D.;
Serena S. Hu M.D.;
David S. Bradford, M.D.
UCSF, Dept of Orthopaedic Surgery, San Francisco, California, USA

INTRODUCTION:
The preferred method of lumbosacral fixation for long fusion to the sacrum is controversial. The purpose of our study is to compare the clinical outcome and complications of three methods of lumbosacral fixation for adult spinal deformities: Luque Galveston, Iliac Screws and Sacral Screws.

METHODS:
Fifty–six consecutive patients who underwent elective combined anterior fusion with structural allograft and posterior surgical reconstruction for adult spinal deformity were included. The average age was 56 years (25 to 73), with a minimum follow up two years. Group one consists of eleven patients with smooth L–rod and segmental sub–laminar wire instrumentation –Luque–Galveston (LG). Group two consists of thirty–nine patients with posterior Isola segmental instrumentation and iliac screw fixation (IS). Group three consists of twelve patients with Isola segmental instrumentation with bicortical sacral screws (SS). Five patients were revised for a total of 61 cases. Radiographs were evaluated and long term outcome data was obtained using the modified SRS outcome instrument.

RESULTS:
The ages of the groups were: LG (56.5 years), IS (57.2 years) and SS (49.6 years). Comparison of peri–operative complications among the three groups showed no difference. The overall peri–operative complication rate was 36%. There were 24 late complications. Eight patients developed pseuadrthrosis requiring revision surgery, four (36%) in the LG group, three (7.5%) in the IS group, and one (8.5%) in the SS group. Nine patients (23%) with iliac screw fixation had painful hardware requiring removal of the iliac fixation. Major curves in the LG group were corrected 45%, in the IS group 35%, and in the SS group 36%. Lordosis improved by 7 degrees in the LG group, by 18 degrees in the IS group and by 12 degrees in the SS group. Comparison of the Modified SRS outcomes showed no difference between the groups when solid arthrodesis was achieved. The average SRS grand total score for LG was 73)%, for IS was 70%, and for SS was 66%. The overall average for the entire group was 69.1%. Overall 77% of the patients were satisfied with their outcome, 14% were neither satisfied nor dissatisfied and only 3 patients were not satisfied.

DISCUSSION:
For adult deformity, the Luque–Galveston technique demonstrated an unacceptably high rate of pseudarthrosis. Segmental fixation combined with Iliac screws provides rigid fixation with a predictable fusion rate. However, screw prominence could be a significant problem required re–operation for implant removal. Bicortical Sacral Screw fixation with anterior structural allograft at L5– S1 provides a rigid construct with an excellent fusion rate in patients with good bone stock when coronal and sagittal balance can be restored