title: Kinematics of the posterior cruciate ligament/posterolateral corner-injured knee after reconstruction by single- and double-bundle intra-articular grafts.
abstract: BACKGROUND
  Single- and double-bundle reconstructions have been proposed for the knee after combined posterior cruciate ligament/posterolateral corner injuries.
  
  
  OBJECTIVE
  The double-bundle posterior cruciate ligament reconstruction is superior to the single-bundle posterior cruciate ligament reconstruction with regard to restoration of normal knee kinematics to the posterior cruciate ligament/posterolateral corner-sectioned knee.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Kinematics of 8 fresh-frozen, cadaveric human knees were determined in the following conditions: intact, sectioned posterior cruciate ligament/posterolateral corner, single anterolateral bundle posterior cruciate reconstruction, and double-bundle posterior cruciate reconstruction.
  
  
  RESULTS
  The sectioned knee demonstrated a posterior shift of the tibial neutral position and the abnormal posterior, varus, and external rotation laxities used clinically to define a combined posterior cruciate ligament/posterolateral corner injury. Both reconstructions restored the posterior laxity to levels that were not statistically different from those seen in the intact knee, but the double-bundle reconstruction more closely mimicked the posterior laxity profile of the intact knee, having statistically lower posterior laxities than did the single-bundle reconstruction at 30 degrees, 60 degrees, and 90 degrees of flexion (P < .05, analysis of variance, HSD test). The resting position of the tibia after double-bundle reconstruction trended to be anteriorly subluxated relative to its position for the intact knee at flexion angles of 30 degrees and greater (P <.05, paired t test). Neither technique corrected the abnormal varus or external rotation laxities.
  
  
  CONCLUSIONS
  With either single- or double-bundle reconstructions, additional posterolateral reconstruction is recommended to correct the external rotation laxity.
  
  
  CONCLUSIONS
  Knowledge of the kinematics of the combined posterior cruciate ligament/posterolateral corner-injured knee is important in the proper diagnosis of the injury and in the selection of the appropriate surgical reconstruction.
authors.affiliation: Walter A. Hoyt, Jr, Musculoskeletal Research Laboratory, Department of Orthopaedic Surgery, Summa Health System, PO Box 2090, 444 North Main Street, Akron, OH 44309-2090, USA.
authors.forename: William B
authors.initials: WB
authors.lastname: Wiley
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Askew
authors.forename: Arne
authors.initials: A
authors.lastname: Melby
authors.forename: Donald A
authors.initials: DA
authors.lastname: Noe
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D002102:Cadaver; D006801:Humans; D007718:Knee Injuries / Q000601:surgery*; D016119:Posterior Cruciate Ligament / Q000293:injuries / Q000601:surgery*; D019651:Plastic Surgery Procedures / Q000379:methods*; D019737:Transplants