title: Likelihood of ACL graft rupture: not meeting six clinical discharge criteria before return to sport is associated with a four times greater risk of rupture.
abstract: BACKGROUND
  The decision as to whether or not an athlete is ready to return to sport (RTS) after ACL reconstruction is difficult as the commonly used RTS criteria have not been validated.
  
  
  OBJECTIVE
  To evaluate whether a set of objective discharge criteria, including muscle strength and functional tests, are associated with risk of ACL graft rupture after RTS.
  
  
  METHODS
  158 male professional athletes who underwent an ACL reconstruction and returned to their previous professional level of sport were included. Before players returned to sport they underwent a battery of discharge tests (isokinetic strength testing at 60°, 180° and 300°/s, a running t test, single hop, triple hop and triple crossover hop tests). Athletes were monitored for ACL re-ruptures once they returned to sport (median follow-up 646 days, range 1-2060).
  
  
  RESULTS
  Of the 158 athletes, 26 (16.5%) sustained an ACL graft rupture an average of 105 days after RTS. Two factors were associated with increased risk of ACL graft rupture: (1) not meeting all six of the discharge criteria before returning to team training (HR 4.1, 95% CI 1.9 to 9.2, p≤0.001); and (2) decreased hamstring to quadriceps ratio of the involved leg at 60°/s (HR 10.6 per 10% difference, 95% CI 10.2 to 11, p=0.005).
  
  
  CONCLUSIONS
  Athletes who did not meet the discharge criteria before returning to professional sport had a four times greater risk of sustaining an ACL graft rupture compared with those who met all six RTS criteria. In addition, hamstring to quadriceps strength ratio deficits were associated with an increased risk of an ACL graft rupture.
authors.affiliation: Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
authors.forename: Polyvios
authors.identifier: http://orcid.org/0000-0002-7765-9407
authors.initials: P
authors.lastname: Kyritsis
authors.affiliation: Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar Department of Sports Medicine, Oslo Sports Trauma Research Center, Norwegian School of Sports Science, Oslo, Norway.
authors.forename: Roald
authors.initials: R
authors.lastname: Bahr
authors.affiliation: Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
authors.forename: Philippe
authors.initials: P
authors.lastname: Landreau
authors.affiliation: Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
authors.forename: Riadh
authors.initials: R
authors.lastname: Miladi
authors.affiliation: Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar Department of Physical Therapy and Motor Rehabilitation, Ghent University, Gent, Belgium.
authors.forename: Erik
authors.initials: E
authors.lastname: Witvrouw
mesh_terms: D000070598:Anterior Cruciate Ligament Injuries / Q000503:physiopathology / Q000601:surgery*; D059549:Anterior Cruciate Ligament Reconstruction / Q000592:standards*; D001265:Athletic Injuries / Q000503:physiopathology* / Q000601:surgery; D054874:Athletic Performance / Q000502:physiology; D050376:Bone-Patellar Tendon-Bone Grafting / Q000592:standards; D006085:Graft Survival / Q000502:physiology; D000070633:Hamstring Muscles / Q000502:physiology; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D010351:Patient Discharge; D052097:Quadriceps Muscle / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology; D012008:Recurrence; D000068958:Return to Sport / Q000502:physiology*; D012307:Risk Factors; D012421:Rupture; D055815:Young Adult
keywords: ACL; Rehabilitation; Risk factor; Sports