Vertebral body tethering (VBT) is a safe and efficacious technique in preventing skeletally immature idiopathic scoliosis patients from having fusion surgery, new research—published by Darren Lui (St. George’s Hospital, London, UK) et al in the Bone and Joint Open Journal—has shown.
The retrospective analysis, which the researchers state is the first report at five years that highlights that two methods of VBT—growth modulation (GM) and anterior scoliosis correction (ASC)—can be employed depending on the skeletal maturity of the patient, showed a high success rate (95%) in helping children avoid fusion at five years’ post-surgery.
The researchers analysed the clinical and radiological data of 20 patients (19 female, one male) aged between nine and 17 years old, between January 2014 to December 2016 with a mean five-year follow-up.
There were ten patients each in the VBT-GM group and the VBT-ASC group respectively, with a total of 23 curves operated on. The VBT-GM mean age was 12.5 years (9 to 14) with a mean Risser classification of 0.63 (0 to 2), and the VBT-ASC mean age was 14.9 years (13 to 17) with a mean Risser classification of 3.66 (3 to 5).
Mean preoperative VBT-GM Cobb angle was 47.4° (40° to 58°) with a Fulcrum unbend of 17.4 (1° to 41°), compared to VBT-ASC 56.5° (40° to 79°) with 30.6 (2° to 69°) unbend.
Postoperative VBT-GM was 20.3° and VBT-ASC Cobb angle was 11.2°. The early postoperative correction rate was 54.3% versus 81% whereas Fulcrum Bending Correction Index was 93.1% vs. 146.6%. The last Cobb angle on radiograph at mean five years’ follow-up was 19.4° in the VBT-GM group and 16.5° in the VBT-ASC group.
Patients with open triradiate cartilage had three over-corrections. Overall, 5% of patients required fusion. This one patient alone had an over-correction, a second-stage tether release, and final conversion to fusion.
Speaking to Spinal News International, Lui said: “Identifying scoliosis early is key and we believe that school screening or scoliosis education programmes will be important in delivering non fusion scoliosis treatment from bracing to VBT.”
Jason Bernard (London, UK)—who along with Tim Bishop (London, UK) were the lead surgeons on the cases involved in the study—added: “Really delighted for those young patients who may be one step closer to avoiding fusion surgery for their scoliosis. I think a new paradigm for earlier treatment is developing.”