title: Computed tomography scan to detect traumatic arthrotomies and identify periarticular wounds not requiring surgical intervention: an improvement over the saline load test.
abstract: OBJECTIVE
  To report our experience with computed tomography (CT) scans to detect traumatic arthrotomies of the knee (TAK) joint based on the presence of intra-articular air.
  
  
  METHODS
  Retrospective review.
  
  
  METHODS
  Level I trauma center.
  
  
  METHODS
  Sixty-two consecutive patients (63 knees) underwent a CT scan of the knee in the emergency department and had a minimum of 14 days follow-up. Cohort of 37 patients (37 knees) from the original 62 patients who underwent a saline load test (SLT).
  
  
  METHODS
  CT scan and SLT.
  
  
  METHODS
  Positive traumatic arthrotomy of the knee (+TAK) was defined as operating room (OR) confirmation of an arthrotomy or no intra-articular air on CT scan (-iaCT) (and -SLT if performed) with follow-up revealing a septic knee. Periarticular wound equivalent to no traumatic arthrotomy (pw = (-TAK)) was defined as OR evaluation revealing no arthrotomy or -iaCT (and -SLT if performed) with follow-up revealing no septic knee.
  
  
  RESULTS
  All 32 knees with intra-articular air on CT scan (+iaCT) had OR confirmation of a TAK and none of these patients had a knee infection at a mean follow-up of 140.0 ± 279.6 days. None of the 31 patients with -iaCT had a knee infection at a mean follow-up of 291.0 ± 548.1 days. Based on these results, the sensitivity and specificity of the CT scan to detect +TAK and pw = (-TAK) was 100%. In a subgroup of 37 patients that received both a CT scan and the conventional SLT, the sensitivity and specificity of the CT scan was 100% compared with 92% for the SLT (P < 0.001).
  
  
  CONCLUSIONS
  CT scan performs better than the conventional SLT to detect traumatic knee arthrotomies and identify periarticular knee wounds that do not require surgical intervention and should be considered a valid diagnostic test in the appropriate clinical setting.
  
  
  METHODS
  Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: Department of Orthopaedic Surgery, NYU Hospital for Joint Diseases, New York, NY 10003, USA.
authors.forename: Sanjit R
authors.initials: SR
authors.lastname: Konda
authors.forename: Roy I
authors.initials: RI
authors.lastname: Davidovitch
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Egol
mesh_terms: D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D003955:Diagnostic Tests, Routine / Q000379:methods*; D004636:Emergency Service, Hospital; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007718:Knee Injuries / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D007719:Knee Joint / Q000000981:diagnostic imaging*; D008297:Male; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018805:Sepsis / Q000453:epidemiology; D012965:Sodium Chloride; D014057:Tomography, X-Ray Computed; D014947:Wounds and Injuries / Q000150:complications* / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D055815:Young Adult
chemical_list: D012965:Sodium Chloride