Correlating femoral shape with patellar kinematics in patients with patellofemoral pain

Abstract

Summary The etiology of patellofemoral pain is likely related to pathological femoral shape and soft-tissue restraints imbalance. These factors may result in various maltracking patterns in patients with patellofemoral pain. Thus, we hypothesized that femoral shape influences patellofemoral kinematics, but that this influence differs between kinematically-unique subgroups of patients with patellofemoral pain. 3D MRIs of 30 knees with patellofemoral pain and maltracking (“maltrackers”) and 33 knees of asymptomatic subjects were evaluated retrospectively. Dynamic MRI was acquired during a flexion-extension task. Maltrackers were divided into two subgroups (non-lateral and lateral maltrackers) based on previously defined kinematic criteria. Nine measures of femoral trochlear shape and two measures of patellar shape were quantified. These measures were correlated with patellofemoral kinematics. Differences were found in femoral shape between the maltracking and asymptomatic cohorts. Femoral shape was correlated with patellofemoral kinematics, but the kinematic parameters that demonstrated significant correlation varied across maltracking subgroups. Femoral shape parameters were associated with patellar kinematics in patients with patellofemoral pain and maltracking, but the correlations were unique across subgroups within this population. The ability to better categorize patients with patellofemoral pain will likely improve treatment by providing a more specific etiology of maltracking in individual patients.

The association of infrapatellar fat pad oedema with patellar maltracking: a case–control study

“…There is an association between trochlear dysplasia and patellar maltracking. Differences were found in femoral shape between maltracking and asymptomatic cohorts in a recent patellofemoral kinematics study [19]. It was also shown that trochlear dysplasia is an important contributing factor to patellofemoral instability [20].…”

Development of a statistical shape model of the patellofemoral joint for investigating relationships between shape and function

“…Innocenti et al (2011) carried out a design-of-experiments (DOE) style analysis (varying patella alta/baja position and internal-external (I-E) rotation, as well as tibial parameters) in four different implanted geometries, determining that PF contact forces were primarily affected by patellar height. Several studies have investigated correlations between PF kinematics and patellar or femoral shape measures in the natural knee (Harbaugh et al, 2010;Sheehan et al, 2009;Jafari et al, 2008;Powers, 2000). Heinert et al (2011) and implanted knees in a cadaveric study, attributing kinematic differences to sulcus groove geometry.…”

Predictors of Patellofemoral Pain Applying Full Weight Bearing Kinematic MRI

“…It has been reported that there is a mismatch between the bony and cartilaginous anatomy of the trochlea (Staubli et al 1999;Shih et al 2004) but possible influence on patellar instability was not evaluated. Harbaugh et al (2010) and Teng et al (2014) reported that the lateral trochlear inclination (LTI) was more important in predicting patellar lateral displacement, than sulcus angle.…”

“…We hypothesized that females with PFP might have greater medial femoral rotation when compared to the pain free individuals. different opinions exist regarding morphometric characteristics of the patellofemoral joint and their influence on patellar alignment and PFP (Powers 2000;Harbaugh et al 2010;Varadarajan et al 2010). The purpose of this study was to use full weight bearing kinematic MRI, to systematically examine relationships among patellofemoral malalignment; morphologic features of the trochlea groove, femoral and patellar rotation and to determine which measures are the best predictors for PFP.…”