Do overweight Adolescent Idiopathic Scoliosis (AIS) patients have an increased perioperative risk for Posterior Spinal Fusion (PSF) surgery? A propensity score matching analysis of 374 AIS patients.

METHODS

Retrospective study OBJECTIVE.: To compare the perioperative outcome of posterior spinal fusion (PSF) between overweight (OW) AIS patients and the healthy-weight (HW) using propensity score matching analysis.

BACKGROUND

Obesity was found to increase postoperative surgical complications compared to the non-obese group. In scoliosis correction surgery, association of overweight and perioperative risks had been explored but most studies were retrospective in nature.

METHODS

From 374 patients, two comparable groups were matched using propensity score matching analysis with one to one nearest neighbor matching and a caliper of 0.2. There were 46 HW and OW patients in each group. The main outcome measures were intra-operative blood loss, use of allogeneic blood transfusion, operative time, duration of hospital stay post-surgery, total PCA morphine usage, perioperative complications, side bending flexibility (SBF), and correction rate (%).

RESULTS

The mean age was 13.3 ± 1.7 and 13.3 ± 1.7 for HW and OW groups respectively. The majority of the patients were Lenke 1 curves; 32.6% (HW) and 26.1% (OW) with an average Cobb angle of 69.0 ± 19.1 and 68.8 ± 18.4° for each groups, respectively. The two groups were comparable. The operation time was 145.2 ± 42.2 minutes and 154.4 ± 48.3 minutes for HW and OW groups (p > 0.05). The intraoperative blood loss was almost similar in both groups; 955.1 ± 497.7 mls (HW group) and 1011.8 ± 552.7 mls (OW group) (p > 0.05). Total PCA morphine used was higher in OW group (30.4 ± 22.7 mg) compared to HW group (16.2 ± 11.3 mg). No complication was observed in HW group, while in OW group one patient (2.2%) developed intraoperative seizure.

CONCLUSIONS

OW AIS patients (≥85th percentile) had similar mean operative time, intraoperative blood loss, allogeneic transfusion rate, length of stay and perioperative complications compared to HW AIS patients.

METHODS

3.