Vitamin D: Should we be checking levels before spine fusion?

Vitamin D is a prohormone that regulates calcium absorption from the gastrointestinal tract. It plays an important role in calcium homeostasis and calcium has several important roles in transmission of nerve impulses, muscle contraction, and proper mineralization of bone. An alarmingly high prevalence of vitamin D deficiency has been described in numerous segments of the U.S. population, with recent studies estimating a prevalence rate of approximately 70%. Several epidemiological studies have reported direct relationships between low vitamin D levels and multiple disease states. Hypovitaminosis D is particularly worrisome in patients undergoing spinal surgery given the high incidence of pseudoarthrosis in this patient cohort. When considering treatment of vitamin D deficiency, it is important to take into account the recommended concentrations and the recommended dietary allowance. Considering the adverse effects of hypovitaminosis D in patients undergoing spine surgery, routine pre-operative screening should be undertaken to identify at-risk patients. In addition, it is important for patients undergoing spinal fusion procedures to maintain a sufficient serum vitamin D concentration (>30 ng/mL).