Prevalence of patellofemoral pain syndrome in young Thai athletes registered in Phitsanulok Provincial Administrative Organization Sports School, Thailand

Background: Patellofemoral pain syndrome (PFPS) is one of the most common knee pain diagnoses in sports medicine clinics. The disorder is usually related with sports and activities of daily living and the condition may affect up to 25% of males and females who participate in sporting activities. However, only researchers in Europe, Australia, USA, and a few Asian countries have conducted studies of prevalence of PFPS. There is still a lack of good epidemiological evidence studying incidence or prevalence of PFPS in most countries. PFPS is also often related to overuse so recent changes in activities and changes in frequency, intensity, and duration of training should be considered.

Objectives: Primary aim of the study was to estimate the prevalence of PFPS in young Thai athletes and the secondary aim was to investigate the relationship between PFPS and training duration per week.

Materials and methods: Three hundred and sixty-two young Thai athletes (12-18 years) were recruited in the study. The participants completed a self-reported questionnaire known as “Anterior Knee Pain Scale (AKPS)” for the initial screening process. Participants who provided a score of less than 100 underwent further physical examination for PFPS. Details of their training schedule according to training frequency per week and types of training were given by sports coaches at school.

Results: Three hundred and ten athletes (mean age: 14.8±1.6 years) completed the Anterior Knee Pain Scale (AKPS) questionnaire. There were 51 (35 males and 16 females) out of 310 participants who reported a questionnaire score of less than 100. Nineteen (12 males and 7 males) out of 51 participants presented with PFPS with a greater prevalence in females. However, no significant difference of PFPS prevalence was found between males and females (males: 12/35 = 34%, females: 7/16 = 44%, p=0.521). The overall prevalence of PFPS was 6% (19 out of 310). PFPS was weakly related to longer sports training duration (r=0.115, p=0.042) for the overall population. When genders were considered, PFPS was weakly related to both longer general training duration (r=0.174, p=0.011) and sports training duration (r=0.147, p=0.033) for males.

Conclusion: The overall prevalence of PFPS in young Thai athletes was 6% which was a lower rate compared to previous studies. Sports training duration and sum of both training duration significantly presented weak correlation with PFPS. The results of the current study may have implications for coaches or sports teachers for planning the schedule of sports training duration for the young Thai athletes.