Halo Gravity Traction Can Mitigate Preoperative Risk Factors and Early Surgical Complications in Complex Spine Deformity

Abstract

STUDY DESIGN:

Retrospective review of prospective cohort. OBJECTIVE:

We sought to examine the role of halo gravity traction (HGT) in reducing preoperative surgical risk. SUMMARY OF BACKGROUND DATA:

The impact of HGT on procedure choice, preoperative risk factors, and surgical complications has not been previously described. METHODS:

Patients treated with HGT before primary surgery were included. The FOCOS Score (FS) was used to quantify operative risk. FS was calculated using patient-factors (ASIA, body mass index, etiology), procedure-factors (PcF; osteotomy planned, number of levels fused, etc.), and curve magnitude (CM). Scores ranged from 0 to 100 with higher scores indicating increased risk. FS was calculated before and after HGT to see how changes in FS affected complication rates. RESULTS:

A total of 96 patients were included. Halo-related complications occurred in 34% of patients but revision was required in only 8.3%. Average FS improved by 18 points after HGT. CM, PcF, and patient-factors all improved (P < 0.05). The greatest changes were in CM and PcF. The planned rate of three-column osteotomies dropped from 91% to 38% after HGT. FS (area under the curve [AUC]: 0.68, P = 0.023) and change in FS (AUC: 0.781, P < 0.001) was successfully able to predict the rate of surgical complications. A preoperative FS of 74 was identified as a cut-off for a higher rate of surgical complications (sensitivity 58.8%, specificity 74.7%). Patients with a reduction in FS < = 10pts were five times more likely to have a complication (relative risk 5.2, 95% confidence interval: 1.9-14.6, P < 0.001). A multivariate regression showed that change in FS was an independent predictor of complication rates (P < 0.05). CONCLUSION:

FS can successfully predict surgical risk in pediatric patients with complex spinal deformity. Preoperative HGT can reduce FS and surgical risk by improving CM, lowering three-column osteotomies use, and improving body mass index. A reduction in FS after HGT predicts a lower rate of surgical complications. LEVEL OF EVIDENCE:

3.