High-dose bone morphogenetic protein–induced ectopic abdomen bone growth

Background contextInfuse [bone morphogenetic protein (BMP)] is increasingly used in spinal fusion surgery.PurposeThe authors report a rare complication of BMP use.Study designThis is a case report.Patient sampleA 55-year-old male underwent a thoracic T8 to the pelvis fusion for degenerative lumbar disc disease and pseudarthrosis at another institution. The procedure involved an anterior and posterior approach with the use of multiple units of BMP.MethodsThe patient presented to our institution with complaints of weight loss, pain, tenderness, and increasing solid growth in the left lower quadrant several months after his surgery. A computed tomography revealed ectopic bone growth in the retroperitoneal area and pelvis contiguous to the anterior lumbar exposure.ResultsThe anterior wound was reexplored, and a large sheet of ectopic bone was removed from the retroperitoneal space.ConclusionsWe report a rare case of extraspinal ectopic bone growth because of the use of multiple packages of BMP.