Patellofemoral pain syndrome: is it okay to use lunges?

German Athletics Championships – June 6, 2021 Germany’s Robin Erewa, Owen Ansah and Steven Muller in action during the men’s 200m final REUTERS/Annegret Hilse

Paper title: Patellofemoral joint loading during the forward and backward lunge

Publication: Physical Therapy in Sport. Jan 2021; Vol. 47, Pages 178-184 https://doi.org/10.1016/j.ptsp.2020.12.001

Publication date: Jan 2021

INTRODUCTION

Patellofemoral pain syndrome (PFPS) is one of the most common causes of knee pain in young athletes. It usually presents as anterior and retro-patellar knee pain made worse by stair climbing, squatting, and running. Eventually, the pain may stop an athlete from playing. Alterations in patellofemoral joint (PFJ) loading variables contribute to PFPS, making it challenging to manage.

Though exercise is the mainstay of PFPS treatment, there is still uncertainty about the best types of exercises and strategies for load progression. The lunge is a popular strengthening and loading exercise. This study sought to discover which kind of lunge, forward or backward, put more stress on the PFJ.

METHODOLOGY

Researchers recruited 20 young, healthy females for this study. They placed 47 body markers on different body parts to record the data from two force platforms and 15 motion analysis cameras. Human Body Model (Motek Medical) was used to measure muscle forces. Participants performed 10 consecutive forward and backward lunges, and the investigators analyzed the middle six.

RESULTS AND CLINICAL IMPLICATIONS

The main findings were as follows:

• Forward and backward lunges were not similar in terms of PFJ loading parameters. Peak PFJ reaction force was 18.1% higher for the forward lunge (FL) than the backward lunge (BL) during upward phase, whereas peak PFJ stress was 9.55% higher in FL than BL.
• Peak quadriceps force was 18.3% higher in FL. The average PFJ loading rate was 124% higher in FL compared to the BL. On average, the angle of knee flexion was 5.85% larger in the upward phase of FL than BL, whereas the ankle was 295% more dorsiflexed during the upward phase of the FL than the BL. And lastly, there was 223% more forward trunk tilt (15.4 degrees) in BL than in FL.

Though based on asymptomatic female participants, these results suggest that there is a higher level of PFJ loading in the FL than the BL. The BL may be a more suitable exercise to strengthen the glutes and quads without adding further strain to the PFJ during PFPS rehabilitation.

ASHIS GUPTA, PT, MPT