title: Knee joint proprioception in ACL-deficient knees is related to cartilage injury, laxity and age: a retrospective study of 54 patients.
abstract: BACKGROUND
  ACL-deficient patients have been found to have proprioceptive defects, but the cause of these defects has not been identified nor has the relationship between proprioception and subjective function, laxity, activity level and age been adequately studied.
  
  
  METHODS
  Therefore, we analyzed proprioception, defined as the threshold to detect a slow passive motion (TTDPM), in relation to activity level, laxity, meniscal injuries, collateral ligament injuries, cartilage injuries, age and subjective function in 54 patients with a previous ACL rupture. We used multiple pair-wise correlation analyses, followed by a stepwise linear regression model.
  
  
  RESULTS
  We found that poorer proprioception was related to lateral cartilage lesions, increased laxity and older age while a high activity level before injury was related with better proprioception after injury. The results also suggest a relation between proprioception and subjective knee function.
  
  
  CONCLUSIONS
  Anatomical injuy classification may need to be considered when discussing proprioceptive ability in patients with an ACL injury, laxity is related to proprioception and proprioception may decrease with age.
authors.affiliation: Department of Orthopedics, University Hospital, SE-221 85 Lund, Sweden. david.roberts@ort.lu.se
authors.forename: David
authors.initials: D
authors.lastname: Roberts
authors.forename: Gert
authors.initials: G
authors.lastname: Andersson
authors.forename: Thomas
authors.initials: T
authors.lastname: Fridén
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D016118:Anterior Cruciate Ligament / Q000503:physiopathology; D000070598:Anterior Cruciate Ligament Injuries; D002358:Cartilage, Articular / Q000293:injuries* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000150:complications / Q000503:physiopathology*; D007718:Knee Injuries / Q000150:complications / Q000503:physiopathology*; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D009043:Motor Activity / Q000502:physiology; D011434:Proprioception / Q000502:physiology*; D012189:Retrospective Studies; D015599:Trauma Severity Indices