Rib construct for severe spinal deformity in young children: a 3-part investigation of biomechanical, animal, and...

Early-onset spinal deformity (EOSD), occurring before age 10, requires surgical techniques that accommodate spinal growth. Traditional intra-spinal methods like growing rods have high complication rates. The rib construct is an alternative technique that uses rib-based fixation for correcting EOSD. The objective of this study is to evaluate its performance.

Biomechanical bending and torsional tests on 20 harvested pig spines compared the pull-out and twisting forces between the rib construct and pedicle screw. For the animal study, hyperkyphosis was induced in 6 immature pigs and subsequently corrected using the rib construct; radiographic and histological evaluations assessed the correction outcomes. Retrospective clinical data on 14 patients (8 male, 6 female) treated with the rib construct for severe nonidiopathic spinal deformity were studied including diagnosis, age at index surgery, length of follow-up, T-score bone density, complication rates, procedure time, operative blood loss, and radiographic outcomes.

Biomechanical testing studies demonstrated that the rib construct was less prone to proximal fixation failure and less stiff compared to pedicle screws. Animal model studies demonstrated improvement in spinal alignment in hyperkyphotic pigs instrumented with the rib construct. Finally, clinical study outcomes demonstrated excellent deformity correction with the rib construct and a reduction in serious complications compared to other techniques.

The rib construct effectively corrects spinal deformity through growth modulation while supporting spinal growth and pulmonary development. It substantially reduces the incidence of severe complications commonly associated with EOSD treatments and is particularly beneficial in cases involving hyperkyphosis and/or osteoporosis.