title: Factors associated with a more rapid recovery after anterior cruciate ligament reconstruction using multivariate analysis.
abstract: BACKGROUND
  In the past, several studies investigated factors that are prognostic or associated with outcome after anterior cruciate ligament (ACL) reconstruction. A recent review showed that only limited evidence is available for most studied factors, and that insufficient analysis methods were used commonly. Therefore, the aim of this study was to add more weight to the existing evidence, about factors that are associated with a more rapid outcome after ACL reconstruction. The second aim was to use multivariate analysis to study the possible factors independently.
  
  
  METHODS
  A cohort study was conducted with a follow-up of six months. Before surgery, patient variables were scored. Surgical variables were scored during arthroscopic ACL reconstructions with a single-bundle technique and hamstring autograft. The Lysholm score and subscales of the Knee Injury Osteoarthritis Outcome Score (KOOS) were assessed six months post surgery. A multiple analysis of variance (ANOVA) model was used to identify prognostic factors for outcome.
  
  
  RESULTS
  In total, 118 patients were included. Patients, aged ≤30years, with a subjective knee score ≥ six, with normal flexion range of motion (ROM) of the knee, with flexion and extension strength deficit of ≤20%, and those with no previous knee surgery in the same knee at baseline scored significantly higher on outcome after multivariate analysis. No significant effect of surgical factors could be found.
  
  
  CONCLUSIONS
  Younger age, higher subjective knee score, normal knee flexion, normal knee flexion and extension strength, and no previous knee surgery in the patients' history at baseline are associated with a more rapid recovery after ACL reconstruction.
  
  
  METHODS
  Level III, prognostic study.
authors.affiliation: VU University Medical Center, Department of Orthopaedic Surgery, Amsterdam, The Netherlands; Bergman Clinics, Department of Orthopedic Surgery and Sports Medicine, Naarden, The Netherlands.
authors.forename: Job E
authors.initials: JE
authors.lastname: Scherer
authors.affiliation: Bergman Clinics, Department of Orthopedic Surgery and Sports Medicine, Naarden, The Netherlands; The Sportsphysician Group, St. Lucas Andreas Hospital, Amsterdam, The Netherlands. Electronic address: m.moen@bergmanclinics.nl.
authors.forename: Maarten H
authors.initials: MH
authors.lastname: Moen
authors.affiliation: Aspetar Orthopaedic and Sports Medicine Hospital, Department of Sport Medicine, Qatar.
authors.forename: Adam
authors.initials: A
authors.lastname: Weir
authors.affiliation: University Medical Center Utrecht, Department of Public Health and Medicine, Utrecht, The Netherlands.
authors.forename: Sandor L
authors.initials: SL
authors.lastname: Schmikli
authors.affiliation: Medicort Sports and Orthopedic Care, Utrecht/Naarden, The Netherlands.
authors.forename: Rob
authors.initials: R
authors.lastname: Tamminga
authors.affiliation: Bergman Clinics, Department of Orthopedic Surgery and Sports Medicine, Naarden, The Netherlands.
authors.forename: Henk
authors.initials: H
authors.lastname: van der Hoeven
mesh_terms: D000328:Adult; D016118:Anterior Cruciate Ligament / Q000503:physiopathology / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries / Q000503:physiopathology / Q000601:surgery*; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D011379:Prognosis; D016059:Range of Motion, Articular / Q000502:physiology*; D020127:Recovery of Function; D012189:Retrospective Studies; D013997:Time Factors
keywords: ACL injury; ACL reconstruction; Outcome; Prognostic factors