Should symptomatic iliac Screws be electively removed in postoperative adult spinal deformity patients fused to the sacrum?

2009

SUMMARY

Of 395 consecutive ambulatory patients who had iliac screws placed during fusion to the sacrum for adult spinal deformity at one institution, 24 (6.1%) underwent elective removal. Using a numeric rating scale for pain, patients had a statistically significant improvement in hip/buttock pain after iliac screw removal and a low prevalence of complications following the procedure was observed.

INTRODUCTION

Iliac screws (IS) are an effective method to counter cantilever forces imparted on sacral fixation. Pain or implant prominence can lead to elective IS removal. Our purpose was to determine: (1) the prevalence of elective IS removal in adult spinal deformity; (2) if symptoms improved after IS removal; (3) complications of IS removal.

METHOD

395 consecutive ambulatory adult deformity patients fused to the sacrum with IS at a single institution were studied. All patients had min 2-yr f/u. Clinical-radiographic data was analyzed. An 8-question IS removal questionnaire was designed and utilized.

RESULTS

24/395 (6.1%) patients (2M/22F) with mean age 50.5±10.8-yrs underwent elective IS removal 2.6±1.3-yrs from the index operation. Mean follow-up from initial surgery was 6.3±4.0-yrs. Hip/buttock pain was present in all 24 pts; 5 pts (20.8%) also reported IS prominence. Removal was bilateral in 18 (79.2%) and unilateral in 5 pts (20.8%). Using a (0-10) NRS pain scale, hip/buttock pain improved following IS removal: pre-op 6.9±1.8, post-op 2.0±2.7 (p<0.05). Patients reported hip/buttock symptoms post-IS removal as: "much improved" (78.3%), "somewhat improved" (8.7%), and "unchanged" (13.0%). 2/24 (8.3%) patients sustained complications from IS removal (wound infection n=1; coronal/sagittal imbalance n=1). Presented with the same set of circumstances, 22/24 (91.7%) of patients would have their IS removed again, including one of the patients who had a complication.

CONCLUSION

In the adult spinal deformity population, the prevalence of elective IS removal was 6.1% at an average of 2.6±1.3-yrs post-op. IS removal was associated with a low rate of complications, a high rate of hip/buttock pain relief (86.0% of patients were improved), and 91.7% overall satisfaction in well selected adult spinal deformity patients.

SIGNIFICANCE

Elective iliac screw removal due to pain or prominence is uncommon following surgery for adult spinal deformity. In carefully selected patients, elective removal of iliac screws results in a significant improvement in hip/buttock pain and high overall satisfaction, with a low risk of complications.