Aseptic loosening of pedicle screw as a result of metal wear debris in a pediatric patient

Abstract

Study design: This is a case report.

Objective: To report a case of soft-tissue reaction to wear debris and osteolysis around a pedicle screw after posterior spine fusion in a pediatric patient.

Summary of background data: Posterior spine fusion with instrumentation is a standard procedure for stabilization and curve correction in patients with scoliosis. Late operative site pain accounts for the highest frequency of reoperation. Debris accumulation for steel and titanium constructs occurs at the pedicle screw-rod junction. Cellular reaction to metal wear may be responsible for osteolysis and aseptic loosening around spinal implants.

Methods: A 14-year-old male patient with neurofibromatosis and right thoracic scoliosis of 50° underwent posterior spine fusion from T2 to T10. The postoperative course was complicated by continuous pain, and imaging studies demonstrated hardware failure, requiring a revision and subsequent development of a perihilar opacity of unknown origin. Further studies demonstrated hypermobility with adjacent soft-tissue reactivity and inflammation surrounding the right T5 transpedicle screw.

Results: After hardware removal, the patient's recovery was uneventful. Six months later, a repeated computed tomographic scan demonstrated resolution of the previously described soft-tissue mass and a satisfactory fusion of the thoracic spine.

Conclusion: Metal wear debris can form in pediatric patients during the healing process after spinal fusions or when pseudarthrosis is present. Clinically, this manifests as back pain with a possible aseptic inflammatory abscess. Hardware removal can achieve resolution of symptoms and regression of inflammation.