title: Symptomatic ectopic bone formation after off-label use of recombinant human bone morphogenetic protein-2 in transforaminal lumbar interbody fusion.
abstract: OBJECTIVE
  Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been approved for use in the lumbar spine in conjunction with the lumbar tapered cage. However, off-label use of this osteoinductive agent is observed with anterior fusion applications as well as with both posterior lumbar interbody fusion and transforaminal lumbar interbody fusion (TLIF). Complications using rhBMP-2 in the cervical spine have been reported. Although radiographic evidence of ectopic bone in the lumbar spine has been described following rhBMP-2 use, this finding was not previously believed to be of clinical relevance.
  
  
  METHODS
  This study was a retrospective review of 4 patients who underwent minimally invasive spinal TLIF (MIS-TLIF) in which bone fusion was augmented with rhBMP-2 applied to an absorbable collagen sponge. Case presentations, operative findings, imaging data, and follow-up findings were reviewed.
  
  
  RESULTS
  Four cases with delayed symptomatic neural compression following the off-label use of rhBMP-2 with MIS-TLIF were identified.
  
  
  CONCLUSIONS
  Although previously believed to be only a radiographic finding, the development of ectopic bone following rhBMP-2 use in lumbar fusion can be clinically significant. This paper describes 4 cases of delayed neural compression following MIS-TLIF. The reader should be aware of this potential complication following the off-label use of rhBMP-2 in the lumbar spine.
authors.affiliation: Division of Neurosurgery, Department of Surgery, Armed Forces Kaohsiung General Hospital, Kaohsiung, Taiwan.
authors.forename: Nan-Fu
authors.initials: NF
authors.lastname: Chen
authors.forename: Zachary A
authors.initials: ZA
authors.lastname: Smith
authors.forename: Eric
authors.initials: E
authors.lastname: Stiner
authors.forename: Sean
authors.initials: S
authors.lastname: Armin
authors.forename: Hormoz
authors.initials: H
authors.lastname: Sheikh
authors.forename: Larry T
authors.initials: LT
authors.lastname: Khoo
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000368:Aged; D055396:Bone Morphogenetic Protein 2 / Q000009:adverse effects* / Q000627:therapeutic use; D017586:Diskectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000175:diagnosis / Q000601:surgery*; D007796:Laminectomy; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D009192:Myelography; D009408:Nerve Compression Syndromes / Q000139:chemically induced / Q000175:diagnosis / Q000601:surgery; D056687:Off-Label Use; D009999:Ossification, Heterotopic / Q000139:chemically induced* / Q000175:diagnosis / Q000601:surgery; D011183:Postoperative Complications / Q000139:chemically induced* / Q000175:diagnosis / Q000601:surgery; D019919:Prosthesis Implantation / Q000379:methods*; D011994:Recombinant Proteins / Q000009:adverse effects / Q000627:therapeutic use; D012086:Reoperation; D013123:Spinal Fusion / Q000379:methods*; D013126:Spinal Nerve Roots / Q000601:surgery; D013168:Spondylolisthesis / Q000175:diagnosis / Q000601:surgery*; D014057:Tomography, X-Ray Computed
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D011994:Recombinant Proteins