Impingement of Spinal Cord by Dislocated Rib in Dystrophic Scoliosis Secondary to Neurofibromatosis Type 1 Radiological Signs and Management Strategies

Study Design. Case series. Objective. To define radiologic diagnosis and treatment strategies of rib dislocation to prevent serious complications during deformity surgery. Summary of Background Data. Rib dislocation into the spinal canal caused by the dystrophic changes seen in scoliotic patients with neurofibromatosis type 1 (NF-1) may cause severe complications when neglected. The risk of this complication is increased by modern instrumentation techniques that produce greater correction. Methods. Three neurologically intact neurofibromatosis patients with scoliosis on whom rib dislocations were determined on convex side of the apical vertebrae were evaluated. Results. Three cases were operated with modern instrumentation and correction techniques either with anterior and posterior approaches with or without rib head excisions, to prevent cord injury. There were no neurologic complications postoperatively. Conclusion. Apical convex rib head dislocation into the canal in NF-1 scoliotic patients can be suspected by conventional radiograms and be proven by CT and MRI. The rib dislocation is not a contraindication to deformity correction with modern spinal instrumentation techniques when preventive measures are applied.