title: The effect of trochleoplasty on patellar stability and kinematics: a biomechanical study in vitro.
abstract: Objective patellar instability has been correlated with dysplasia of the femoral trochlea. This in vitro study tested the hypothesis that trochleoplasty would increase patellar stability and normalise the kinematics of a knee with a dysplastic trochlea. Six fresh-frozen knees were loaded via the heads of the quadriceps. The patella was displaced 10 mm laterally and the displacing force was measured from 0 degrees to 90 degrees of flexion. Patellar tracking was measured from 0 degrees to 130 degrees of knee flexion using magnetic sensors. These tests were repeated after raising the central anterior trochlea to simulate dysplasia, and repeated again after performing a trochleoplasty on each specimen. The simulated dysplasia significantly reduced stability from that of the normal knee (p < 0.001). Trochleoplasty significantly increased the stability (p < 0.001), so that it did not then differ significantly from the normal knee (p = 0.244). There were small but statistically significant changes in patellar tracking (p< 0.001). This study has provided objective biomechanical data to support the use of trochleoplasty in the treatment of patellar instability associated with femoral trochlear dysplasia.
authors.affiliation: Department of Mechanical Engineering, Imperial College London, London, England. a.amis@imperial.ac.uk
authors.forename: A A
authors.initials: AA
authors.lastname: Amis
authors.forename: C
authors.initials: C
authors.lastname: Oguz
authors.forename: A M J
authors.initials: AM
authors.lastname: Bull
authors.forename: W
authors.initials: W
authors.lastname: Senavongse
authors.forename: D
authors.initials: D
authors.lastname: Dejour
mesh_terms: D001696:Biomechanical Phenomena / Q000379:methods; D002102:Cadaver; D019317:Evidence-Based Medicine; D006801:Humans; D007593:Joint Instability / Q000209:etiology / Q000601:surgery*; D010027:Osteotomy / Q000379:methods*; D010329:Patella / Q000033:anatomy & histology / Q000601:surgery*; D013314:Stress, Mechanical