Larger screw on the concave side of apex pedicle: Friend or foe? Report on a rare cause of neurological deficit in scoliosis surgery

Larger screw on the concave side of apex pedicle: Friend or foe? Report on a rare cause of neurological deficit in scoliosis surgery: Bhavuk Garg, Nishank Mehta, Ashok Jaryal



Indian Spine Journal 2020 3(1):114-117



Pedicle screw instrumentation is currently the “gold standard” in scoliosis surgery. However, placement of pedicle screws in thoracic spine is considered challenging. Previous studies have described morphometric changes in the pedicle when a larger screw is inserted, with pedicle expansion preceding screw cutout and pedicle fracture. We report an unusual case of neurological deficit due to cord compression by an expanded pedicle following pedicle screw insertion on the concave side of the apical vertebra in a 14-year-old patient with Lenke Type 3C(-) adolescent idiopathic scoliosis. Identification of the expanded pedicle as the cause of neurological symptoms, prompt action, and deferring the corrective surgery while accepting less correction helped us in negotiating the problem without causing permanent neurological deficit. Pedicle expansion in an immature spine can cause neurological complications. The screw diameter at the apical vertebrae on the concave side should be carefully selected.