Knee Function and Pain Related to Psychological Variables in Patients With Long-Term Patellofemoral Pain Syndrome

Abstract

Nonexperimental, descriptive study, including 2 independent samples. To assess the levels of mental distress and self-perceived health in subjects with long-term patellofemoral pain syndrome (PFPS) compared to a group of healthy subjects, and the relationship between knee function and knee pain to these psychological variables. Psychological variables and those describing self-perceived health status have been given little focus in PFPS research. One group of 25 men and women between 19 and 44 years of age with unilateral long lasting PFPS, and a control group (n = 23) of healthy subjects (age range, 18-44 years) participated in the study. Knee function was assessed with the use of the Cincinnati Knee Rating System (CKRS) and the triple jump test, and knee pain was measured by a visual analogue scale (VAS). Self-perceived health and mental distress were assessed with the Coop-Wonca Chart and the Hopkins Symptoms Checklist-25 (HSCL-25) questionnaire. The mean (+/- SD) score on the Coop-Wonca Chart was 2.02 +/- 0.73 in the PFPS group, compared to 1.20 +/- 0.53 in the controls (P < .001). HSCL-25 mean (+/- SD) scores were 1.46 +/- 0.47 and 1.08 +/- 0.18 (P < .001) for the PFPS and the control group, respectively. When analyzed with correlation statistics, CKRS and VAS scores were found to correlate to those of the Coop-Wonca Chart and HSCL-25 scores. Levels of mental distress were higher in the group with PFPS than in the control group, while levels of self-perceived health were lower. Our data indicate that the levels of knee pain and knee function correlate closely to the degree of mental distress and self-perceived health in individuals with PFPS.