Spinal Fusion in Patients with Osteopetrosis and Other Disorders of High Bone Mineral Density: A Report of Two Cases

Osteopetrosis encompasses a group of rare metabolic bone disorders in which the bones are abnormally dense due to defective osteoclastic bone resorption. The presence of this condition in patients requiring spinal fusion with instrumentation for deformity or degenerative conditions poses unique challenges to the surgical procedure and possibly obtaining spinal fusion. Existing literature on osteopetrosis is scarce, especially in association with spinal fusion. The objective of this report is to discuss the challenges and related outcomes associated with spinal fusion in patients who have osteopetrosis. Two patients underwent spinal fusion to treat various conditions of the lumbar vertebrae. They were discovered to have abnormally dense bones that delayed the surgical procedure and were subsequently referred for an endocrinology workup for osteopetrosis. Both spinal fusions were exceptionally difficult due to the dense bone. Both patients experienced an improvement in symptoms and showed intact spinal fusion at a minimum follow-up of 2 years. One of the patients was diagnosed with osteopetrosis after an endocrinology workup. Successful spinal fusion is possible in patients with osteopetrosis, although the procedure is more technically demanding than the standard procedure, which may increase the risk of surgical complications.