Abstract

New technology and instrumentation techniques are continually entering the spine field, leaving the scoliosis surgeon with a wide variety of options for the treatment of adolescent idiopathic scoliosis. All-screw constructs are currently the most popular. However, they remain controversial because of possible complications, and also because they have been associated with a decrease in thoracic kyphosis, not observed with hybrid instrumentation. The aim of the present study was to evaluate a hybrid construct : hooks and wires proximally, but pedicle screws distally. Forty-three patients with a minimum 2-year follow-up were included. The mean preoperative Cobb angle of the major curve was 60.85° ± 21°. At the final evaluation it was reduced to 28.44° ± 11.9° (mean correction 53.3%, p < 0.0001). The mean translation of the apical vertebra was corrected from -19.13 ± 49 mm to -9.42 ± 28.9 mm. The average thoracic kyphosis improved from 24° ± 14.3° preoperatively to 30.7° ± 7.1°, representing a mean correction of 28%. Kyphosis at the T10-L2 level was within normal values in all patients at the final evaluation. Complications included one superficial infection, one implant removal due to late onset wound infection, and 2 revisions to extend the fusion more distally. In other words, operative treatment with hybrid instrumentation yielded satisfactory results, with less risk of neurological damage. An excellent outcome in all planes could be safely achieved and maintained for a minimum of 2 years. Conclusion : why use an expensive all-screw construct, knowing that a hybrid construct is kyphosis sparing, cheaper, safer and more resistant to pull-out ?