Kinematic and Neuromuscular Deficiencies Phenotypes Associated With Patellofemoral Pain Syndrome : a Cross-sectional Interventional Study Protocol

Abstract

Background: The physiopathology of PFPS is multifactorial and includes static and dynamic dysfunctions which have not been fully elucidated to date. Among numerous classifications, a pragmatic classification distinguishes 3 major clinical phenotypes: PFPS with objective displacement of the patella, PFPS with extra-patellar alignment problem and PFPS without alignment problems. The relationships between the clinical and biomechanical factors are still unclear.

Objective : The primary aim of this study is to describe and compare the kinematic deficiencies specifically associated with each of the 3 main clinical phenotypes. The secondary aim is to describe and compare neuromuscular deficiencies, postural and proprioceptive associated with each of the 3 main clinical phenotypes.

Method: PHENOPAT is a comparative, non-randomized study. We will use the KneeKG device (EMOVI) to assess the 3D knee rotations, EoS Imaging to assess femoro-tibial alignment and isokinetic device to measure hip abductor, quadriceps and hamstrings muscle strength and endurance. The unipodal static and dynamic stability will be assessed by the Y test and posturography. We will compare the kinematic deficiencies using a rank comparison or a mean comparison test between 2 groups or between 3 groups according to the distribution of participants between the groups.

Discussion: We expect to observe specific biomechanical factors correlated with each main clinical phenotypes. We wish that will help to enable a more specific diagnosis and treatment.