BACKGROUND The purpose of this prospective study was to assess the impact of closed suction drainage on transfusion requirements, frequency of dressing changes, and wound healing following posterior spinal fusion in adolescents with idiopathic scoliosis. METHODS Thirty patients were randomly assigned to one of two groups: drain or no drain. Although the group with drains received more postoperative autologous blood transfusions than the group with no drains (0.88 vs 0.5 unit), the difference was not statistically significant (P = 0.2131). In the undrained group, 58% of the patients had moderate to completely saturated dressings on the second postoperative day compared with only 17% of patients in the drained group. Three of 12 patients in the undrained group demonstrated a wound complication rate compared with no complications in the drained group. CONCLUSION In conclusion, subcutaneous closed suction drainage can improve immediate postoperative wound care without significantly increasing blood loss and transfusion requirements for patients undergoing surgery for idiopathic scoliosis.