Rees D1, Younis A1, Macrae S2,3
1St. George's University of London, Department of Health, Social Care and Education, Tooting, United Kingdom, 2Brunel University, London, United Kingdom, 3Chelsea and Westminster Hospital NHS Foundation Trust, London, United Kingdom
Background: Patellofemoral pain syndrome is the most common injury to befall runners and as such represents a major barrier to a physically active lifestyle. Whilst proposed to be multifactorial in nature, knee kinematics whilst running, specifically knee valgus, have been proposed as a key precipitating factor to developing this condition. Assessing running gait would therefore appear key to successful management but this practice requires skill, equipment and time often lacking in busy therapy departments. Clinically, the easier to administer and analyze single leg squat is used to make inferences about knee kinematics during running. No evidence supports this practice.
Purpose: This research study aimed to investigate if a correlation exists between frontal plane knee kinematics during a single leg squat and when running for runners with patellofemoral pain syndrome and for asymptomatic runners., Furthermore, this paper investigated if frontal plane knee kinematics during a) running and b) single leg squat were different in runners with patellofemoral pain syndrome compared to asymptomatic runners.
Methods: Sixteen asymptomatic runners (mean age 31.7yrs (range 27-36yrs), eleven females: five males) were recruited from running and triathlon clubs via email invitation. Sixteen runners with patellofemoral pain syndrome (mean age 32.4yrs (range 25-42yrs), eleven females: five males) were recruited from the outpatient physiotherapy department of a London hospital. Asymptomatic runners were sub-divided by dominant and non-dominant leg and the runners with patellofemoral pain syndrome by painful and non-painful leg. This gave four groups. Participants were videoed performing i) single leg squats and ii) running on a treadmill. Frontal plane knee kinematics were calculated at peak knee flexion for both running and the single leg squat using the frontal plane projection angle. The final outcome measure was calculated as the average of three single leg squats and three consecutive running strides respectively. Correlation in frontal plane projection angle between running and single leg squat was calculated using Pearson's Correlation Coefficient. Differences in frontal plane projection angle between groups for both running and single leg squat were calculated using multiple independent t-tests with Bonferroni correction.
Results: Correlation in frontal plane projection angle between running and the single leg squat was not statistically significant for the painful leg group (runners with patellofemoral pain syndrome (p=0.19)); statistical significance was observed for the remaining three groups (p 0.05). There was no statistically significant difference in frontal plane projection angle between the four groups when running. Single leg squat frontal plane projection angle was significantly larger for the painful leg patellofemoral pain syndrome group (10.3°) than the dominant leg (-0.2° (p=0.02)) and non-dominant leg (-0.4° (p=0.001)) in the asymptomatic group.
Conclusion(s): The single leg squat should not be used to make inferences about frontal plane knee kinematics in running gait for people with patellofemoral pain syndrome. Knee valgus is larger in runners with patellofemoral pain syndrome than asymptomatic runners during a single leg squat but not when running.
Implications: : Based on these findings the inclusion of a running gait analysis during the assessment of runners with patellofemoral pain syndrome is recommended.
Keywords: Running, Movement, Analysis
Funding acknowledgements: Completed as part of a Masters of Research in Clinical Practice (MResCP) funded through the National Institute of Health Research.
Purpose: This research study aimed to investigate if a correlation exists between frontal plane knee kinematics during a single leg squat and when running for runners with patellofemoral pain syndrome and for asymptomatic runners., Furthermore, this paper investigated if frontal plane knee kinematics during a) running and b) single leg squat were different in runners with patellofemoral pain syndrome compared to asymptomatic runners.
Methods: Sixteen asymptomatic runners (mean age 31.7yrs (range 27-36yrs), eleven females: five males) were recruited from running and triathlon clubs via email invitation. Sixteen runners with patellofemoral pain syndrome (mean age 32.4yrs (range 25-42yrs), eleven females: five males) were recruited from the outpatient physiotherapy department of a London hospital. Asymptomatic runners were sub-divided by dominant and non-dominant leg and the runners with patellofemoral pain syndrome by painful and non-painful leg. This gave four groups. Participants were videoed performing i) single leg squats and ii) running on a treadmill. Frontal plane knee kinematics were calculated at peak knee flexion for both running and the single leg squat using the frontal plane projection angle. The final outcome measure was calculated as the average of three single leg squats and three consecutive running strides respectively. Correlation in frontal plane projection angle between running and single leg squat was calculated using Pearson's Correlation Coefficient. Differences in frontal plane projection angle between groups for both running and single leg squat were calculated using multiple independent t-tests with Bonferroni correction.
Results: Correlation in frontal plane projection angle between running and the single leg squat was not statistically significant for the painful leg group (runners with patellofemoral pain syndrome (p=0.19)); statistical significance was observed for the remaining three groups (p 0.05). There was no statistically significant difference in frontal plane projection angle between the four groups when running. Single leg squat frontal plane projection angle was significantly larger for the painful leg patellofemoral pain syndrome group (10.3°) than the dominant leg (-0.2° (p=0.02)) and non-dominant leg (-0.4° (p=0.001)) in the asymptomatic group.
Conclusion(s): The single leg squat should not be used to make inferences about frontal plane knee kinematics in running gait for people with patellofemoral pain syndrome. Knee valgus is larger in runners with patellofemoral pain syndrome than asymptomatic runners during a single leg squat but not when running.
Implications: : Based on these findings the inclusion of a running gait analysis during the assessment of runners with patellofemoral pain syndrome is recommended.
Keywords: Running, Movement, Analysis
Funding acknowledgements: Completed as part of a Masters of Research in Clinical Practice (MResCP) funded through the National Institute of Health Research.
Topic: Musculoskeletal: lower limb; Musculoskeletal: lower limb; Sport & sports injuries
Ethics approval required: Yes
Institution: NRES
Ethics committee: South Central
Ethics number: 15/SC/0333
All authors, affiliations and abstracts have been published as submitted.
