Pedicle Screw Usage in Conventional Fixation Pattern Constructs Compared to Thoracic Hook Constructs in Scoliosis

Pedicle Screw Usage in Conventional Fixation Pattern Constructs Compared to Thoracic Hook Constructs in Adolescent Idiopathic Scoliosis Patients and Neuromuscular Ambulators

Scoliosis is a deformity in which there is an abnormal curvature of the spine. Surgery is the main method of correcting this deformity. Rods are attached to the spine to make it strait. There are two ways to fix these rods to the bone of the spine: laminar hooks or pedicle screws. Hooks are an older form of fixation and do not penetrate the bone, but are instead placed over a part of the vertebra called the lamina. Screws are newer and do penetrate the bone. Screws are placed into the part of the vertebra called the pedicle. Most surgeons think screws correct scoliosis better than hooks. The current literature agrees that screws are better for deformity correction in the lumbar spine and patients with severe deformity. There is disagreement in the literature regarding which works better in the thoracic spine in less severe deformity. There are no randomized, controlled trials in the literature that examine whether constructs that use hooks in the thoracic spine and screws in the lumbar spine (called hybrid constructs) work as well as all-screw constructs. This clinical study is a randomized controlled trial being conducted to evaluate treatment outcomes in patients with scoliosis undergoing surgical correction for their curves using either all-screw or hybrid constructs as fixation devices. The study population is limited to those with less severe deformity and the investigators' hypothesis is that hybrid constructs will be as acceptable as screws in terms of correction.

Inclusion Criteria:

• Primary diagnosis of adolescent idiopathic scoliosis or neuromuscular scoliosis
• Fusion to include six of more levels in thoracic, thoracolumbar, or lumbar region
• Less than 21 years of age
• Able to undergo surgery based on physical exam, medical history, and surgeon judgement
• Willing to comply with the follow-up clinical and radiographic evaluation schedules
• Informed consent signed by patient and parent or legal guardian

Exclusion Criteria:

• Scoliosis with curvature greater than 100 degrees or less than 40
• Smaller juvenile subjects weighing less than 30 kg
• Rigid curves
• Infection in the disc or spine, past or present
• Subject is pregnant
• Evidence of abuse of alcohol and/or illicit drugs
• Subject is prisoner
• Subject has evidence of tumor(s), malignant disease or other significant illness with decreased life expectancy
• Subject is immunocompromised or being treated with immunosuppressive agents