title: Revisit to scapular dyskinesis: three-dimensional wing computed tomography in prone position.
abstract: BACKGROUND
  Three-dimensional (3D) wing computed tomography (CT) showed a high inter-rater reliability in assessing scapular dyskinesis.
  
  
  METHODS
  The 330 scapular movements of 165 patients were classified into 4 types by 7 blinded observers. Then, 3D wing CT was performed with patients prone, and 4 blinded observers measured 5 angles, consisting of upward rotation (UR) superior translation (ST), anterior tilting (AT), protraction (PRO), and internal rotation (IR). The inter-rater reliability (IRR) of 2 methods was calculated, and cutoff values were determined for the 5 angles on the 3D wing CT images.
  
  
  RESULTS
  The IRR was 0.783 for the observational method of scapular dyskinesis and 0.981 for 3D wing CT in the prone position. UR and ST angles were significantly larger in type 3 more than in the other types (P < .001, P < .001), and the AT angle showed a similar pattern in type 1 (P < .001). The PRO angle was significantly larger in types 1, 2, and 3 more than in type 4 (P < .001, P < .001, P = .013), and the IR angle was significantly larger in type 2 more than in the other types (P < .001). The cutoff values of the 5 angles were UR, 117°; ST, 90°; AT, 8°; PRO, 99°; and IR, 51°. The UR angle showed a significant correlation with glenohumeral internal rotation deficit (odds ratio, 0.436; P = .029) and the IR angle with MDI (odds ratio, 8.947; P = .048).
  
  
  CONCLUSIONS
  The patients with a high UR angle showed a low rate of glenohumeral internal rotation deficit and those with a high IR angle had a high rate of the MDI in affected shoulder by the determinant of the cutoff value of the 5 angles.
  
  
  METHODS
  Level III, development of diagnostic criteria with nonconsecutive patients, diagnostic study.
authors.affiliation: Department of Orthopedic Surgery, Konkuk University School of Medicine, Seoul, South Korea; Global Center for Shoulder & Elbow, Department of Orthopedic Surgery, Konkuk University Hospital, Seoul, South Korea.
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Park
authors.affiliation: Department of Orthopedic Surgery, Chuncheon Sacred Heart Hospital, Hallym University Medical College, Chuncheon-si, Gangwon-do, South Korea. Electronic address: drakehjt@hanmail.net.
authors.forename: Jung-Taek
authors.initials: JT
authors.lastname: Hwang
authors.affiliation: Department of Orthopedic Surgery, Konkuk University School of Medicine, Seoul, South Korea; Global Center for Shoulder & Elbow, Department of Orthopedic Surgery, Konkuk University Hospital, Seoul, South Korea.
authors.forename: Kyung-Soo
authors.initials: KS
authors.lastname: Oh
authors.affiliation: Department of Orthopedic Surgery, Konkuk University School of Medicine, Seoul, South Korea; Global Center for Shoulder & Elbow, Department of Orthopedic Surgery, Konkuk University Hospital, Seoul, South Korea.
authors.forename: Seong-Jun
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Radiology, Konkuk University Hospital, Seoul, South Korea.
authors.forename: Na Ra
authors.initials: NR
authors.lastname: Kim
authors.affiliation: Gem Fitness, Seoul, South Korea.
authors.forename: Myung-Joo
authors.initials: MJ
authors.lastname: Cha
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D001696:Biomechanical Phenomena; D002648:Child; D020820:Dyskinesias / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D016684:Prone Position; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D012540:Scapula / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012785:Shoulder Joint / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: 3D wing CT; Scapular dyskinesis; concomitant disease; cutoff value; inter-rater reliability; observational method; prone position