title: Pre-operative quadriceps strength predicts IKDC2000 scores 6 months after anterior cruciate ligament reconstruction.
abstract: BACKGROUND
  Quadriceps strength deficits are ubiquitous after anterior cruciate ligament (ACL) injury. Deficits prior to surgery can influence knee function post-operatively. Inhibition contributes to quadriceps strength deficits after an ACL injury. Body mass index, meniscal injury, and sex influence functional outcomes after ACL reconstruction. The purpose of this study is to examine the relationship of pre-operative quadriceps strength and post-operative knee function and to investigate how other pre-operative factors may influence this relationship.
  
  
  METHODS
  After an ACL injury, subjects received pre-operative rehabilitation and performed quadriceps strength testing. Subjects underwent reconstruction and post-operative rehabilitation. Six months after ACL reconstruction, subjects completed the International Knee Documentation Committee 2000 subjective form (IKDC2000). Linear regression models were developed using IKDC2000 scores at 6 months after ACL reconstruction as the dependent variable.
  
  
  RESULTS
  Fifty-five subjects had complete pre-operative data and IKDC2000 scores at 6 months after ACL reconstruction. Pre-operative involved quadriceps strength was a significant predictor for IKDC2000 scores 6 months after ACL reconstruction. Sex, meniscal injury, pre-operative BMI, and pre-operative involved quadriceps activation ratio were not significant predictors in the regression model.
  
  
  CONCLUSIONS
  Pre-operative quadriceps strength can predict IKDC2000 scores 6 months after ACL reconstruction. Deficits in pre-operative quadriceps strength influence self-reported function 6 months after surgery. Factors that are known to influence quadriceps strength and self-reported outcomes do not influence the relationship between pre-operative quadriceps strength and post-operative IKDC2000 scores.
authors.affiliation: Department of Physical Therapy, University of Delaware, 301 McKinly Lab, Newark, DE 19716, USA. davlog@udel.edu
authors.forename: David
authors.initials: D
authors.lastname: Logerstedt
authors.forename: Andrew
authors.initials: A
authors.lastname: Lynch
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Axe
authors.forename: Lynn
authors.initials: L
authors.lastname: Snyder-Mackler
mesh_terms: D000328:Adult; D016118:Anterior Cruciate Ligament / Q000503:physiopathology / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000534:rehabilitation*; D059026:Diagnostic Self Evaluation; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000503:physiopathology / Q000534:rehabilitation* / Q000601:surgery; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery; D008297:Male; D009119:Muscle Contraction; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D064797:Physical Conditioning, Human; D057234:Preoperative Period; D052097:Quadriceps Muscle / Q000502:physiology*; D011788:Quality of Life; D016059:Range of Motion, Articular; D020127:Recovery of Function; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires