What is the effect of intraoperative traction on correction of adolescent idiopathic scoliosis (AIS)?

PURPOSE: Determine the efficacy of intraoperative traction (IOT) on curve correction in AIS.

METHODS

A prospective, multicenter, longitudinal database identified patients with major thoracic AIS (Lenke 1-4) treated with surgery using IOT and follow-up of 2 years. These cases were matched to comparable cases treated without traction (non-IOT). All patients were treated with single-stage posterior only surgery with pedicle screw constructs. Perioperative, radiographic and clinical outcome data at 2 years post-op were compared between the groups.

RESULTS

104 cases treated with IOT were matched to 104 treated without IOT. Operating room time was significantly greater in the IOT group (339 vs. 306 min, p =  < 0.001). Neuromonitoring alerts were more frequent in the IOT group (23% vs. 5%, p < 0.001). There were no postoperative neurological deficits in either group. The IOT group showed significantly greater MT curve correction (IOT 71% vs. non-IOT 66.7%, p < 0.003), with the effect most pronounced in curves > 70° (IOT 72% vs. non-IOT 64%, p = 0.04). IOT was associated with a significant reduction in 2D T5-T12 kyphosis measurements (IOT - 6.5° vs non-IOT + 0.48°, p < 0.001), yet significant improvements in estimated 3D thoracic kyphosis were made in both groups, with the non-IOT group making greater improvement when compared to the IOT group (IOT + 18.1° vs. non-IOT + 22.3° vs., p = 0.008).

CONCLUSIONS

IOT is associated with modestly enhanced coronal deformity correction. Surgeons should be aware of the increased rates of neuromonitoring alerts when using this technique and its affect on the sagittal profile. Given this IOT may be best suited to larger curves.

LEVEL OF EVIDENCE: 3.