Pseudoarthrosis Repair Using Autologous Cultured Osteoblasts in Complex Type-1 Neurofibromatosis Spinal Deformity. A Case Report and Review of the Literature

A case report and literature review OBJECTIVE.: To report a late dislocation of the vertebra caused by progressive dural ectasia combined with type-1 neurofibromatosis (NF-1) and the clinical results of pseudoarthrosis repairs using autologous cultured osteoblasts. NF-1 is a well-known genetic disorder that is commonly characterized by spinal deformities including kyphoscoliosis. Late dislocation of the vertebra resulting from progressive dural ectasia after surgical correction of NF-1 scoliosis is a very rare occurrence, and pseudoarthrosis frequently develops after surgical intervention for this complex spinal deformity. A 32-year-old female patient with NF-1 scoliosis underwent surgical correction with posterior instrumented fusion (PIF). Seventeen years later, dislocation of the lumbar spine with implant failure resulting from massive progressive dural ectasia was observed. She underwent anterior interbody fusion (AIF) 3 times and PIF 4 times for pseudoarthrosis followed by surgical deformity correction. For the last operation, autologous cultured osteoblasts were used as a therapeutic approach to repair the pseudoarthrosis, and a three-dimensional printing technique was used to understand the surgical anatomy of the dislocated lumbar spine in detail. After the final operation, bone union was achieved and confirmed by clinical and radiological examination. Spine surgeons should be knowledgeable about the possibility of late destabilization of the spine, due to pulsatile dural ectasia, and a high rate of pseudoarthrosis in neurofibromatosis. Autologous cultured osteoblasts may prove to be a modality that can be applied pseudoarthrosis repair to treat complex spinal deformity. 5.