title: Arthroscopic cartilage indentation and cartilage lesions of anterior cruciate ligament-deficient knees.
abstract: BACKGROUND
  The anterior cruciate ligament-deficient knee is prone to osteoarthritis and meniscus lesions. Very little, however, is known about the biomechanical properties of articular cartilage in anterior cruciate ligament-deficient knees.
  
  
  OBJECTIVE
  To evaluate biomechanical and macroscopical cartilage changes in the knee joint with respect to the time after anterior cruciate ligament rupture.
  
  
  OBJECTIVE
  Chronic anterior cruciate ligament deficiency induces cartilage softening.
  
  
  METHODS
  Cross-sectional study; Level of evidence, 3.
  
  
  METHODS
  Cartilage stiffness of 50 patients undergoing anterior cruciate ligament reconstructive surgery because of symptomatic knee instability after chronic anterior cruciate ligament rupture was measured with an arthroscopic indenter device, and the number and size of cartilage lesions were evaluated.
  
  
  RESULTS
  The cartilage stiffness did not correlate with time from trauma to surgery (r = 0.002, P = .99), but the number of cartilage lesions in the knee increased when the time from the initial trauma to reconstructive surgery increased (r = 0.356, P = .011). Indentation values measured on healthy-looking cartilage on damaged joint surfaces were lower than the values measured on healthy joint surfaces (P < .01 on lateral femoral condyle and on tibial plateaus).
  
  
  CONCLUSIONS
  The number of cartilage lesions increases with increased time after initial trauma. The arthroscopic indenter device is able to detect cartilage softening as the early mechanical sign of degradation not yet visible to the eye.
authors.affiliation: Department of Orthopaedics and Traumatology, Helsinki University Hospital, Helsinki, Finland. anna.vasara@fimnet.fi
authors.forename: Anna I
authors.initials: AI
authors.lastname: Vasara
authors.forename: Jukka S
authors.initials: JS
authors.lastname: Jurvelin
authors.forename: Lars
authors.initials: L
authors.lastname: Peterson
authors.forename: Ilkka
authors.initials: I
authors.lastname: Kiviranta
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000473:pathology*; D000070598:Anterior Cruciate Ligament Injuries; D001182:Arthroscopy; D001696:Biomechanical Phenomena; D002358:Cartilage, Articular / Q000293:injuries* / Q000473:pathology*; D005260:Female; D006801:Humans; D007593:Joint Instability; D007718:Knee Injuries / Q000150:complications* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D019651:Plastic Surgery Procedures; D012421:Rupture; D013997:Time Factors