Local and widespread hyperalgesia in female runners with patellofemoral pain are influenced by running volume.

Abstract

To compare pressure pain threshold (PPT) around the knee (local hyperalgesia) and at a site remote to the knee (widespread hyperalgesia) between female runners with and without patellofemoral pain (PFP); and to evaluate the relationship between running volume, self-reported knee function and PPT measures. Cross-sectional study. Twenty female runners with PFP and twenty pain-free female runners participated in the study. PPTs were measured using a handheld pressure algometer at four sites in the patellar region: quadriceps tendon, medial patella, lateral patella and patellar tendon; and on the contralateral upper limb. Additionally, all participants were asked to report their average weekly running volume in a typical month and answer the anterior knee pain scale (AKPS) questionnaire. For all sites, female runners with PFP presented lower PPT measures in comparison with control group (P<0.017). There were negative correlations between AKPS and running volume (ρ=-0.88; P<0.001) and between all PPTs and the running volume in the PFP group with correlation (ρ) values ranging between -0.46 and -0.70 (P<0.022). There were positive correlations between all PPTs and AKPS with correlation (ρ) value from 0.50 to 0.69 (P<0.030). Lower PPTs locally and remote to the knee in female runners with PFP indicate the presence of local and widespread hyperalgesia. Additionally, this hyperalgesia, which is related to self-reported knee function, appears to be increased by greater running volumes. Development and evaluation of non-mechanical interventions for the management of running-related PFP in females may be needed to address this apparent hyperalgesia.