title: Halo pin insertion-associated brain abscess: case report and review of literature.
abstract: METHODS
  A case report of a patient with a halo pin-associated brain abscess and a review of literature.
  
  
  OBJECTIVE
  To report a rare complication of halo pin insertion-associated brain abscess, and to discuss the diagnostic and treatment approach to its management.
  
  
  BACKGROUND
  Halo orthosis is a commonly used, well-tolerated spinal stabilizing device. However, on rare occasions, it can penetrate the inner table of the cranium, resulting in abscess formation that needs to be investigated urgently and treated promptly.
  
  
  METHODS
  A 23-year-old male sustained a C2 vertebral fracture from a motor vehicular accident and was placed in halo traction. Two and a half months later, he noted loosening of the right occipital halo pin, which was tightened in the clinic. Fourteen days after pin tightening, he developed right-sided headaches, and it was decided to remove the halo traction. After the halo removal, the patient noted purulent discharge from the right occipital pin site, worsening headache, and associated nausea and vomiting. Magnetic resonance imaging of the brain demonstrated a right parietal lobe abscess and a sinus tract extending through the overlying calvarium. The patient underwent an evacuation of the abscess, and the culture was positive for methicillin-resistant Staphylococcus aureus. The patient was treated with intravenous vancomycin for 6 weeks.
  
  
  RESULTS
  The patient reported mediated improvement after surgery and on a follow-up visit was doing well without any neurologic sequelae.
  
  
  CONCLUSIONS
  Halo pin-associated brain abscess is a rare but extremely important complication requiring prompt diagnosis and immediate intervention. Halo pin loosening with signs of local infection, fever, headaches, or seizures needs to be investigated urgently with neuroimaging. We conclude that with early diagnosis and appropriate treatment, serious morbidity and mortality can be avoided.
authors.affiliation: Department of Infectious Diseases, St. Louis University, St. Louis, MO 63110-0250, USA. msaeed@slu.edu
authors.forename: Musab U
authors.initials: MU
authors.lastname: Saeed
authors.forename: Mary Abigail C
authors.initials: MA
authors.lastname: Dacuycuy
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Kennedy
mesh_terms: D000328:Adult; D001368:Axis, Cervical Vertebra / Q000293:injuries*; D001858:Bone Nails / Q000009:adverse effects*; D001915:Braces; D001922:Brain Abscess / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D016103:Spinal Fractures / Q000628:therapy*; D014143:Traction