title: Diagnostic Accuracy of Imaging Modalities and Injection Techniques for the Diagnosis of Femoroacetabular Impingement/Labral Tear: A Systematic Review With Meta-analysis.
abstract: BACKGROUND
  Diagnosing femoroacetabular impingement/acetabular labral tear (FAI/ALT) and subsequently making a decision regarding surgery are based primarily on diagnostic imaging and intra-articular hip joint injection techniques of unknown accuracy.
  
  
  OBJECTIVE
  Summarize and evaluate the diagnostic accuracy and clinical utility of various imaging modalities and injection techniques relevant to hip FAI/ALT.
  
  
  METHODS
  Systematic review with meta-analysis.
  
  
  METHODS
  A computer-assisted literature search was conducted of MEDLINE, CINAHL, and EMBASE databases using keywords related to diagnostic accuracy of hip joint pathologic changes. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were used for the search and reporting phases of the study. Quality assessment of bias and applicability was conducted using the Quality of Diagnostic Accuracy Studies (QUADAS) tool. Random effects models were used to summarize sensitivities (SN), specificities (SP), likelihood ratios (+LR and -LR), diagnostic odds ratios (DOR), and respective confidence intervals (CI).
  
  
  RESULTS
  The search strategy and assessment for risk of bias revealed 25 articles scoring above 10/14 on the items of the QUADAS. Four studies investigated FAI, and the data were not pooled. Twenty articles on ALT qualified for meta-analysis. Pretest probability of ALT in the studies in this review was 81% (72%-88%), while the pretest probability of FAI diagnosis was 74% (95% CI, 51%-91%). The meta-analysis showed that computed tomography arthrography (CTA) demonstrated the strongest overall diagnostic accuracy: pooled SN 0.91 (95% CI, 0.83-0.96); SP 0.89 (95% CI, 0.74-0.97); +LR 6.28 (95% CI, 2.78-14.21); -LR 0.11 (95% CI, 0.06-0.21); and DOR 64.38 (95% CI, 19.17-216.21).
  
  
  CONCLUSIONS
  High pretest probability of disease was demonstrated. Positive imaging findings increased the probability that a labral tear existed by a minimal to small degree with the use of magnetic resonance imaging/magnetic resonance angiogram (MRI/MRA) and ultrasound (US) and by a moderate degree for CTA. Negative imaging findings decreased the probability that a labral tear existed by a minimal degree with the use of MRI and US, a small to moderate degree with MRA, and a moderate degree with CTA.
  
  
  CONCLUSIONS
  Although findings of the included studies suggested potentially favorable use of these modalities for the diagnosis of ALT and FAI, our results suggest that these findings have limited generalizability and clinical utility given very high pretest prevalence, large confidence intervals, and selection criteria of the studies. Registration: PROSPERO Registration #CRD42015027745.
authors.affiliation: Duke University Medical Center, Department of Orthopedic Surgery, Durham, North Carolina, USA.|Sports Orthopedic Research Centre-Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Copenhagen, Denmark.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Reiman
authors.affiliation: Sports Orthopedic Research Centre-Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Copenhagen, Denmark.|Physical Medicine & Rehabilitation Research-Copenhagen (PMR-C) and Departments of Orthopaedic Surgery and Physical Therapy, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: Kristian
authors.initials: K
authors.lastname: Thorborg
authors.affiliation: Duke University Medical Center, Department of Orthopedic Surgery, Durham, North Carolina, USA.
authors.forename: Adam P
authors.initials: AP
authors.lastname: Goode
authors.affiliation: Duke University Medical Center, Department of Orthopedic Surgery, Durham, North Carolina, USA.
authors.forename: Chad E
authors.initials: CE
authors.lastname: Cook
authors.affiliation: AMC, Amsterdam Center of Evidence Based Sports Medicine (ACES), Amsterdam, North Holland, The Netherlands.|Aspetar Sports Groin Pain Center, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
authors.forename: Adam
authors.initials: A
authors.lastname: Weir
authors.affiliation: Sports Orthopedic Research Centre-Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Copenhagen, Denmark.|Aspetar Sports Groin Pain Center, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
authors.forename: Per
authors.initials: P
authors.lastname: Hölmich
mesh_terms: D001175:Arthrography / Q000379:methods; D057925:Femoracetabular Impingement / Q000000981:diagnostic imaging*; D006621:Hip Joint / Q000000981:diagnostic imaging; D006801:Humans; D022125:Lacerations / Q000000981:diagnostic imaging*; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography
keywords: diagnostic accuracy; hip; hip arthroscopy