title: The effect of a dynamic PCL brace on patellofemoral compartment pressures in PCL-and PCL/PLC-deficient knees.
abstract: BACKGROUND
  The natural history of posterior cruciate ligament (PCL) deficiency includes the development of arthrosis in the patellofemoral joint (PFJ). The purpose of this biomechanical study was to evaluate the hypothesis that dynamic bracing reduces PFJ pressures in PCL- and combined PCL/posterolateral corner (PLC)-deficient knees.
  
  
  METHODS
  Controlled Laboratory Study.
  
  
  METHODS
  Eight fresh frozen cadaveric knees with intact cruciate and collateral ligaments were included. PFJ pressures and force were measured using a pressure mapping system via a lateral arthrotomy at knee flexion angles of 30°, 60°, 90°, and 120° in intact, PCL-deficient, and PCL/PLC-deficient knees under a combined quadriceps/hamstrings load of 400 N/200 N. Testing was then repeated in PCL- and PCL/PLC-deficient knees after application of a dynamic PCL brace.
  
  
  RESULTS
  Application of a dynamic PCL brace led to a reduction in peak PFJ pressures in PCL-deficient knees. In addition, the brace led to a significant reduction in peak pressures in PCL/PLC-deficient knees at 60°, 90°, and 120° of flexion. Application of the dynamic brace also led to a reduction in total PFJ force across all flexion angles for both PCL- and PCL/PLC-deficient knees.
  
  
  CONCLUSIONS
  Dynamic bracing reduces PFJ pressures in PCL- and combined PCL/PLC-deficient knees, particularly at high degrees of knee flexion.
authors.affiliation: Kerlan Jobe Orthopaedic Clinic, Los Angeles, CA, USA. tpwelch14@gmail.com.
authors.forename: Tyler
authors.initials: T
authors.lastname: Welch
authors.affiliation: Kerlan Jobe Orthopaedic Clinic, Los Angeles, CA, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Keller
authors.affiliation: Kerlan Jobe Orthopaedic Clinic, Los Angeles, CA, USA.
authors.forename: Ruben
authors.initials: R
authors.lastname: Maldonado
authors.affiliation: Kerlan Jobe Orthopaedic Clinic, Los Angeles, CA, USA.
authors.forename: Melodie
authors.initials: M
authors.lastname: Metzger
authors.affiliation: Kerlan Jobe Orthopaedic Clinic, Los Angeles, CA, USA.
authors.forename: Karen
authors.initials: K
authors.lastname: Mohr
authors.affiliation: Kerlan Jobe Orthopaedic Clinic, Los Angeles, CA, USA.
authors.forename: Ronald
authors.initials: R
authors.lastname: Kvitne
keywords: Patellofemoral joint; Peak pressure; Posterior cruciate ligament; Posterolateral corner