Rhabdomyolysis after spinal fusion surgery: management schema and prevention of a catastrophic complication

Purpose: Rhabdomyolysis is a clinical syndrome with the potential to cause cardiac arrhythmias, renal failure, and even death. Currently, there are no studies regarding risk factors for developing post-operative rhabdomyolysis (POR) after spinal fusion surgeries. Our objective was to study risk factors associated with, and to develop a decision-making framework for post-operative rhabdomyolysis after spinal fusion surgery. Methods: We performed a retrospective cohort study of all spinal fusions of three or more levels over 2.25 years by a single surgeon at two centers. POR was defined as a creatine phosphokinase (CPK) greater than 2000 IU/L. Results: 76 surgical procedures on 72 patients were identified. Rate of POR in our cohort was 22% (17/76). Male sex was associated with POR (p < 0.05). Previously validated risk factors: younger age, lower ASA score, elevated BMI, higher pre-operative creatinine, increased intraoperative blood loss, specific surgical positions, and length of surgery, were not associated with POR. In a logistic regression model, male gender increases the odds of POR in all patients 5.82-fold (p = 0.047). In patients without a second surgery within seven days, a logistic regression model suggests each additional level fused via transpsoas approach, and male gender, increases the risk of POR 1.81-times (p = 0.015), and 6.26-times (p = 0.047), respectively. In patients with posterior fusions, a logistic regression model suggests increasing the number of lateral levels fused via transpsoas approach in the same surgery, and male gender, increases the risk of POR 1.68-times and 6.34-times, respectively. In these same subgroups, increased thickness of the psoas major in lateral transpsoas fusions increased risk of POR (p = 0.023, p = 0.046, respectively). Conclusions: In spinal fusions, increasing the number of lateral levels fused via transpsoas approach, and male gender, predispose patients to increased risk of POR in those without a second surgery within seven days, and in those with a simultaneous posterior fusion.