title: Neuropathic pain following sagittal split ramus osteotomy of the mandible: prevalence, risk factors, and clinical course.
abstract: OBJECTIVE
  To estimate the prevalence of, risk factors for, and clinical course of neuropathic pain (NPP) after sagittal split ramus osteotomy (SSRO) of the mandible in a large cohort of patients.
  
  
  METHODS
  A retrospective cohort of all patients who underwent SSRO at 2 medical centers within Kaiser Permanente Northern California from January 2007 through September 2012 was assembled. Demographic, clinical, and surgical factors were abstracted from medical records and relevant comorbidities were identified. The prevalence of NPP in the cohort was calculated and the clinical signs, symptoms, temporal characteristics, and treatment response in affected patients were noted.
  
  
  RESULTS
  The authors identified 1,778 patients who underwent SSRO and excluded 107 patients according to predefined criteria. The remaining 1,671 patients had a median age of 24 years (interquartile range, 19 to 35 yr) and 62.4% were women. Seven patients developed NPP after SSRO, which was an overall prevalence of 0.42%. All patients with NPP in this cohort were women and had a median age of 49 years. The risk factors for developing NPP after this surgery were older age (P = .0098), depression (P = .0100), and female gender. NPP developed an average of 30 days postoperatively (range, 18 to 56 days) and persisted for a median duration of 52 days (range, 30 to 69.5 days). All patients responded favorably to anticonvulsant (n = 6) or tricyclic (n = 1) medications, and no patients developed chronic postsurgical pain.
  
  
  CONCLUSIONS
  NPP was an infrequent complication after SSRO, occurring in 1 of 238 patients in this cohort. The short duration and positive response to medication are reassuring findings. The results of this investigation highlight the need for prospective studies to further understand the spectrum of postoperative NPP.
authors.affiliation: Division of Oral and Maxillofacial Surgery, University of the Pacific School of Dentistry, Highland Hospital, Oakland, CA; Division of Maxillofacial Surgery, Kaiser Permanente Medical Center, Oakland, CA; and Division of Maxillofacial Surgery, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Érica C
authors.initials: ÉC
authors.lastname: Marchiori
authors.forename: Jacob S
authors.initials: JS
authors.lastname: Barber
authors.forename: W Bradford
authors.initials: WB
authors.lastname: Williams
authors.forename: Peter Q
authors.initials: PQ
authors.lastname: Bui
authors.forename: Felice S
authors.initials: FS
authors.lastname: O'Ryan
mesh_terms: D000328:Adult; D000367:Age Factors; D000588:Amines / Q000627:therapeutic use; D000927:Anticonvulsants / Q000627:therapeutic use; D000929:Antidepressive Agents, Tricyclic / Q000627:therapeutic use; D015331:Cohort Studies; D003509:Cyclohexanecarboxylic Acids / Q000627:therapeutic use; D003863:Depression / Q000150:complications; D005157:Facial Pain / Q000188:drug therapy / Q000209:etiology*; D005260:Female; D000077206:Gabapentin; D006801:Humans; D008297:Male; D008337:Mandibular Fractures / Q000601:surgery*; D008875:Middle Aged; D009437:Neuralgia / Q000188:drug therapy / Q000209:etiology*; D059229:Osteotomy, Sagittal Split Ramus / Q000009:adverse effects*; D010149:Postoperative Pain / Q000188:drug therapy / Q000209:etiology*; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D012678:Sensation Disorders / Q000188:drug therapy / Q000209:etiology; D012737:Sex Factors; D055815:Young Adult; D005680:gamma-Aminobutyric Acid / Q000627:therapeutic use
chemical_list: D000588:Amines; D000927:Anticonvulsants; D000929:Antidepressive Agents, Tricyclic; D003509:Cyclohexanecarboxylic Acids; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin