Research Fellow NYU Langone Medical Center Paterson, NJ, US
Introduction: single position MIS approach allows access to the anterior and posterior columns with the ability to mitigate complications associated with open procedures while achieving circumferential fusion. Purpose of study was to identify if patient weight or body mass index (BMI) leads to differences in intraoperative event rates.
Methods: MIS patients with positioning and weight/BMI data were included. Patients were stratified into 2 groups: Lateral decubitus [Lat] and Prone Lateral [PL]. Uni- and multivariable analysis were performed. Mean weight and BMI values were compared with and without aborted procedures and a thresholds correlated with increased EBL and OpTime.
Results: 88 met inclusion criteria (52 Lat and 36 PL) male (49, 55.7%), mean age of 49.2 yrs and 2.0 levels fused and 18 (20.5%) undergoing an osteotomy. Lat patients with a weight > 130 kg had significantly longer OpTime (p=0.003) and more EBL (p=0.019). There was a significant difference in mean weight for Lat patients with (121.8 kg) and without (97.7 kg) an aborted procedure, p=0.021. There was also a significant difference in mean BMI for Lat patients with (35.3 kg/m2) and without (29.6 kg/m2) an aborted procedure, p=0.015. Multivariable analysis showed that weight (OR 1.03 [CI 1.01-1.06], p=.020) and BMI (OR 1.15 [CI 1.02-1.30], p=.026) were independent predictors for aborted procedures in Lat patients. In an analysis of PL patients, there was one aborted case (weight > 120 kg), but no significant findings for EBL or OpTime.
Conclusion : Weight and BMI appear to be independently associated with aborted procedures for patients in the lateral decubitus position during minimally invasive spine surgery. Patients in lateral decubitus position who weighed 130 kg or more had on average longer operative times and more estimated blood lost. This study has the potential to help with risk stratification in the future when determining patients undergoing a single position procedure.
