Incidence and Risk Factors for Chronic Anterior Knee Pain

Anterior Knee Pain Risk Differs Between Sex and Occupation in Military Tactical Athletes

CONTEXT

Anterior knee pain (AKP) is ubiquitous in early-career military members and exacerbated during functional tasks required during military duties. Therefore, it is important to understand risk of this condition in male and female tactical athletes in diverse military occupations.

OBJECTIVE

To assess sex and occupation on AKP risk in military members.

DESIGN

Descriptive Epidemiology Study.

SETTING

United States Armed Forces. Patients All military members diagnosed with anterior or retro-patellar pain, patellar instability, knee tendinopathy on their initial encounter from 2006 to 2015.

OUTCOME MEASURES

The Defense Medical Epidemiology Database was queried for the number of individuals with AKP. Relative risk (RR) and chi-square statistics were calculated in the assessment of sex and occupational category. Regressions were calculated to determine association between service branch, sex, and AKP across time.

RESULTS

From 2006-2015, a total of 151,263 enlisted and 14,335 officer services members were diagnosed with AKP. Enlisted females had an incidence rate of 16.7 per 1000 person-years compared to the enlisted male service members with an incidence rate of 12.7 per 1000 person-years (RR: 1.32, 95%CI: 1.30-1.34, p<0.001) across all AKP diagnoses. Female officers had an incidence rate of 10.7 per 1,000 person-years compared to male officers at an incidence rate of 5.3 per 1000 person-years (RR: 2.01, 95%CI: 1.94-2.09). Differences in risk were also noted across military occupation for both enlisted and officer service members (p<.05).

CONCLUSION

Sex and military occupation were salient factors for AKP risk. Evaluation of training requirements and developing interventions programs across military occupation could serve as a focus for future research aiming to mitigate associated risk factors of AKP.

Incidence and prevalence of patellofemoral pain: A systematic review and meta-analysis

BACKGROUND

Patellofemoral pain is considered one of the most common forms of knee pain, affecting adults, adolescents, and physically active populations. Inconsistencies in reported incidence and prevalence exist and in relation to the allocation of healthcare and research funding, there is a clear need to accurately understand the epidemiology of patellofemoral pain.

METHODS

An electronic database search was conducted, as well as grey literature databases, from inception to June 2017. Two authors independently selected studies, extracted data and appraised methodological quality. If heterogeneous, data were analysed descriptively. Where studies were homogeneous, data were pooled through a meta-analysis.

RESULTS

23 studies were included. Annual prevalence for patellofemoral pain in the general population was reported as 22.7%, and adolescents as 28.9%. Incidence rates in military recruits ranged from 9.7-571.4/1,000 person-years, amateur runners in the general population at 1080.5/1,000 person-years and adolescents amateur athletes 5.1%-14.9% over 1 season. One study reported point prevalence within military populations as 13.5%. The pooled estimate for point prevalence in adolescents was 7.2% (95% Confidence Interval: 6.3%-8.3%), and in female only adolescent athletes was 22.7% (95% Confidence Interval 17.4%-28.0%).

CONCLUSION

This review demonstrates high incidence and prevalence levels for patellofemoral pain. Within the context of this, and poor long term prognosis and high disability levels, PFP should be an urgent research priority.

PROSPERO REGISTRATION

CRD42016038870.

[Chronic sports injuries of the knee joint]

Chronic sports injuries of the knee joint are common and mainly caused by repetitive (micro) trauma and exertion. Chronic insertion tendinopathies and avulsion fractures and symptoms related to entrapment, friction and impingement can be pathophysiologically distinguished in athletes. In this review, we depict the characteristic magnetic resonance imaging (MRI) findings of the most commonly occurring pathologies.