Association of postoperative adverse events with low skeletal muscle mass measured from the 12th thoracic vertebral skeletal muscle mass in oral cancer patients

Abstract

Abstract Background Sarcopenia is characterized by a progressive and generalized loss of skeletal muscle mass and strength. The aim of this study was to investigate the impact of skeletal muscle mass on adverse events in free-flap reconstruction for defects after oral cancer resection. Methods The participants were a non-randomized retrospective cohort of 120 patients who underwent this procedure after preoperative diagnostic computed tomography. Cross-sectional areas (cm2) of skeletal muscles in the Th12 region were measured by manual outlining of computed tomography images. Subsequently, the skeletal muscle Cross-sectional areas at level L3 was estimated using the prediction rule described by Matsuyama et al. These areas were then normalized to height (cm2/m2) and defined as the skeletal muscle index. Results Recipient-site adverse events occurred in 56 patients (46.7%), and recipient-site surgical site infections occurred in 45 patients (37.5%). Skeletal muscle index was significantly associated with recipient site adverse events in univariate analysis (P < 0.05). Lower body mass index and skeletal muscle index were significantly associated with recipient site surgical site infection in univariate analysis (P < 0.05). In the multiple logistic regression model, a lower skeletal muscle index was a significant risk factor for recipient site adverse events and surgical site infections (adverse events odds ratio; 3.17/P = 0.04; surgical site infection odds ratio; 3.76/P = 0.02). Conclusions These results suggest that low skeletal muscle index in Th12 is particularly associated with adverse events and that it is a predictor of surgical site infections.