title: Contralateral psoas seroma after transpsoas lumbar interbody fusion with bone morphogenetic protein-2 implantation.
abstract: BACKGROUND
  The lateral transpsoas approach to interbody fusion of the lumbar spine (lateral lumbar interbody fusion [LLIF]) with recombinant human bone morphogenetic protein-2 (BMP-2) augmentation has been increasingly performed in recent years. Potential side effects and adverse sequelae of BMP-2 in the acute setting remain to be fully elucidated.
  
  
  OBJECTIVE
  To review the literature for reports of complications related to BMP-2 implantation in lumbar spinal surgery and present a case of a contralateral psoas muscle seroma after LLIF with BMP-2 implantation.
  
  
  METHODS
  Case report and literature review.
  
  
  METHODS
  The PubMed database was searched for articles related to adverse events to BMP-2 in lumbar spinal surgery. We report the case of a 57-year-old woman who underwent routine right-sided transpsoas approach for LLIF with the use of BMP-2 at our institution and developed a left-sided psoas muscle fluid accumulation 2 weeks postoperatively.
  
  
  RESULTS
  No reports of complications contralateral to an LLIF approach attributable to an inflammatory response to BMP-2 were identified in the English literature. In the presented patient, a large (4.2×6.5×2.7 cm) left-sided sterile intramuscular psoas fluid collection was seen on a magnetic resonance imaging study obtained on postoperative day 14. At a 6-month follow-up, left-sided L5 radiculopathy resulting in 4/5 foot drop was confirmed by electromyography. The patient reported here represents the only case of a contralateral psoas seroma with suspected association to BMP-2 utilization in LLIF encountered at our institution.
  
  
  CONCLUSIONS
  A serous psoas muscle fluid accumulation after BMP-2 implantation may rarely occur contralateral to the surgical approach for LLIF. Further characterization of complications related to BMP-2 implantation after lumbar spinal surgery will help guide preoperative informed decision making and the management of this unusual postoperative adverse event.
authors: Division of Spine Surgery, Department of Orthopedic Surgery, Hospital for Special Surgery, 535 East 70th St, New York, NY 10021, USA. fadi.taher@gmail.com
authors: Fadi
authors: F
authors: Taher
authors: Darren R
authors: DR
authors: Lebl
authors: Alexander P
authors: AP
authors: Hughes
authors: Federico P
authors: FP
authors: Girardi
mesh_terms: D055396:Bone Morphogenetic Protein 2 / Q000009:adverse effects* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000473:pathology / Q000601:surgery; D017116:Low Back Pain / Q000473:pathology / Q000601:surgery; D008159:Lumbar Vertebrae / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D016658:Psoas Muscles / Q000473:pathology / Q000601:surgery*; D049291:Seroma / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D013123:Spinal Fusion / Q000009:adverse effects*
chemical_list: D055396:Bone Morphogenetic Protein 2