title: Copenhagen five-second squeeze: a valid indicator of sports-related hip and groin function.
abstract: BACKGROUND
  No simple clinical measure exits to evaluate groin pain and its severity in athletes. The aim was to investigate the validity, reliability and responsiveness of a five-second hip-adduction squeeze test for football players designed to assess sports-related hip and groin function, pain and severity.
  
  
  METHODS
  Construct validity was assessed in 667 subelite male football players with a mean age (±SD) of 24±4 in the beginning of the season. Responsiveness and reliability were evaluated during the season in 52 and 10 players, respectively. Players answered the Copenhagen Hip and Groin Outcome Score (HAGOS) and performed the Copenhagen five-second squeeze assessed on a Numerical Pain Rating Scale (NRS) ranging from 0 to 10.
  
  
  RESULTS
  As hypothesised higher pain scores during the Copenhagen five-second squeeze correlated significantly (Spearman's rho=-0.61, p<0.01) with a lesser HAGOS (Sport) Score. The change scores in the Copenhagen five-second squeeze also correlated significantly (Spearman's rho=-0.51, p<0.01), with HAGOS (Sport) change scores in the responsiveness analysis, and test-retest reliability (concordance correlation coefficient) was 0.90. Moreover, significant (p<0.01) between-group differences existed for HAGOS (Sport) Scores in players reporting groin pain intensity at one of the 3 different pain levels: NRS (0-2), NRS (3-5) and NRS (6-10). The NRS (6-10) group had the lowest median (IQR) HAGOS (Sport) Score of 47 (31-61).
  
  
  CONCLUSIONS
  The Copenhagen five-second squeeze is a valid indicator of sports-related hip and groin function in football players. Players reporting groin pain intensity as 6 of 10 or more in the Copenhagen five-second squeeze experience substantially impaired sports-related hip and groin function.
authors.affiliation: Department of Orthopedic Surgery, Sports Orthopedic Research Center (SORC-C)-Copenhagen, Copenhagen University Hospital, Amager-Hvidovre, Copenhagen, Denmark.
authors.forename: K
authors.initials: K
authors.lastname: Thorborg
authors.affiliation: Department of Orthopedic Surgery, Sports Orthopedic Research Center (SORC-C)-Copenhagen, Copenhagen University Hospital, Amager-Hvidovre, Copenhagen, Denmark.|Department of Radiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: S
authors.initials: S
authors.lastname: Branci
authors.affiliation: Department of Orthopedic Surgery, Sports Orthopedic Research Center (SORC-C)-Copenhagen, Copenhagen University Hospital, Amager-Hvidovre, Copenhagen, Denmark.
authors.forename: M P
authors.initials: MP
authors.lastname: Nielsen
authors.affiliation: Department of Orthopedic Surgery, Sports Orthopedic Research Center (SORC-C)-Copenhagen, Copenhagen University Hospital, Amager-Hvidovre, Copenhagen, Denmark.
authors.forename: M T
authors.initials: MT
authors.lastname: Langelund
authors.affiliation: Department of Orthopedic Surgery, Sports Orthopedic Research Center (SORC-C)-Copenhagen, Copenhagen University Hospital, Amager-Hvidovre, Copenhagen, Denmark.
authors.forename: P
authors.initials: P
authors.lastname: Hölmich
mesh_terms: D000328:Adult; D056352:Athletes; D001265:Athletic Injuries / Q000175:diagnosis*; D006119:Groin / Q000503:physiopathology*; D006615:Hip / Q000503:physiopathology*; D006801:Humans; D008297:Male; D010146:Pain / Q000503:physiopathology; D010147:Pain Measurement / Q000379:methods*; D010808:Physical Examination / Q000379:methods*; D015203:Reproducibility of Results; D012916:Soccer; D055815:Young Adult
keywords: Football; Groin; Hip; Measurement