The Response of Hip Joint Cartilage to Exercise in Children: An MRI Study Using T2-Mapping

Abstract

Objective The aim of this study was to determine the effects of activity and cam morphology on cartilage composition during adolescence and investigate the development of cartilage composition with age. Design Cross-sectional observational cohort study of individuals from football club academies and an age-matched control population, aged 9 to 18 years. Assessments included questionnaires and T2-mapping of hips. Primary imaging outcome measures were T2 relaxation time of acetabular and femoral cartilage, average alpha angle, and lateral epiphyseal extension. Results The cohort consisted of 109 elite male footballers, 49 male controls, and 51 female controls. Elite male footballers had an acetabular cartilage T2 value 4.85 ms greater than male controls ( P < 0.001). A significant positive correlation existed between Physical Activity Questionnaire Score and acetabular cartilage T2 value (coefficient 1.07, P < 0.001) and femoral cartilage T2 value (coefficient 0.66, P = 0.032). Individuals with a closed physis had an acetabular cartilage T2 value 7.86 ms less than individuals with an open physis. Acetabular cartilage T2 values decreased with age in elite footballers. No correlation existed between alpha angle and anterosuperior acetabular cartilage T2 value and no difference in T2 value existed between individuals with and without cam morphology. Conclusions This study demonstrates that high activity levels may significantly affect acetabular cartilage composition during adolescence, but cam morphology may not detrimentally affect cartilage composition until after adolescence.

Cam morphology is associated with MRI-defined cartilage defects and labral tears: a case–control study of 237 young adult football players with and without hip and groin pain

“…However, in a recent cross-sectional study, cartilage composition did not differ between adolescent football players with and without cam morphology. 11 It is more likely that features of early OA (ie, cartilage defects and labral tears) gradually develop and only present in football players with cam morphology from early adulthood. However, little is known about the relationship between cam morphology and MRI-defined cartilage defects and labral tears in young adult football players.…”

Preventing hip osteoarthritis in athletes: is it really a mission impossible?

“…Adolescence : Changes in articular cartilage composition—a biomarker of early-stage OA—are evident in elite adolescent football players, possibly affecting its tolerance to high joint loads and increasing susceptibility to pathological change 2. This concept is supported by a recent longitudinal study of adolescent athletes where cartilage damage increased over 24 months 3.…”

“…We do not fully understand the pathological interaction between cam morphology and joint structures, although it appears to be inconsequential in most athletes 2 6. Cam morphology might not influence joint structure until after skeletal growth 2…”

“…This developmental process is more pronounced (ie, larger cam morphology) in elite-level athletes and continues until growth plate closure with likely no further development after maturation 4 5. We do not fully understand the pathological interaction between cam morphology and joint structures, although it appears to be inconsequential in most athletes 2 6. Cam morphology might not influence joint structure until after skeletal growth 2…”

“…When considering the natural history of OA in athletes, research has largely focused on primary cam morphology development and associated chondrolabral pathologies 2 7. This neglects the complex aetiology of OA, the role of other hip conditions (eg, hip dysplasia) and the part of symptoms and disability in athlete burden.…”