The aim of the study was to compare the duration of corrective surgery for scoliosis in relation to the intra-operative use of either fluoroscopic or CT navigation. The indication for surgery was adolescent idiopathic scoliosis in younger patients and degenerative scoliosis in middle age or elderly patients.
In a retrospective study, treatment outcomes in 43 consecutive patients operated on between April 2011 and April 2014 were compared. With good teamwork (surgeons, anaesthesiologists and a radiologist attending to the O-arm system), the time required to obtain one intra-operative CT scan is 3 to 5 minutes.
The study showed that the mean time for placement of one screw was identical in both techniques although the average operative time was longer in surgery with O-arm navigation. The 19 minute interval was not the real placement time per screw.
It was the sum of all operative times of surgical procedures (from first incision to suture completion including the whole approach within the range of planned stabilization) which used the same navigation technique divided by the number of all screws inserted during the procedures. The longer average operative time in procedures using O-arm navigation was not related to taking intra-operative O-arm scans.
The authors consider surgery with an O-arm imaging system to be a safer procedure and use it currently in surgical correction of scoliosis. The study focused on the length of surgery to correct scoliosis performed using either conventional fluoroscopy (C-arm) or intra-operative CT scanning (O-arm) showed that the mean placement time for one screw was identical in both imaging techniques when six or more vertebrae were stabilised.
The use of intra-operative CT navigation did not make the surgery longer, and the higher number of inserted screws provides evidence that this technique is safer and allows us to achieve good stability of the correction procedure.