OBJECTIVE: To analyze the results obtained with a new surgical technique for minimally invasive (MIS) isolated posterior approach to the surgical correction of adolescent idiopathic scoliosis (AIS). METHODS: We compared two similar groups of patients with AIS of Lenke type 1A. The groups were similar in age, sex, Cobb angle, apex of the curve, vertebral rotation, thoracic kyphosis, fusion levels, type of instrumentation and follow-up. Group 1 was treated with a mini-invasive technique and Group 2 by the conventional method. We analyzed surgery time, intraoperative blood loss, analgesic requirements in the period immediately after surgery, hospitalization times, rate of screw malposition, loss of correction, rate of pseudoarthrosis, and implant mobilization. RESULTS: In Group 1 (MIS) the surgery significantly decreased bleeding and there was a lower incidence of malpositioned screws in the recess than in the conventionally-treated group, however the surgery lasted longer. Both groups had similar analgesic requirements, and hospitalization times did not differ significantly. In the long-term, neither group showed any cases of non-union, correction losses, or mobilization of the implants. CONCLUSIONS: The MIS technique demonstrated longer surgery time and less blood loss, but did not reduce the analgesic requirements or hospitalization times. Initial correction of scoliosis by convexity decreased the incidence of malpositioned screws in the concavity. There was no losses resulting in correction, mobilization of the implants, or non-union.
Scoliosis; Adolescent; Spine; Bone screws; Surgical procedures, minimally invasive surgery
