Elsevier

Osteoarthritis and Cartilage

Volume 22, Issue 12, December 2014, Pages 2074-2082
Osteoarthritis and Cartilage

Mechanical factors explain development of cam-type deformity

https://doi.org/10.1016/j.joca.2014.09.011Get rights and content
Under an Elsevier user license
open archive

Summary

Objective

A cam-type deformity drastically increases the risk of hip osteoarthritis (OA). Since this type of skeletal anomaly is more prevalent among young active adults, it is hypothesized that the loading conditions experienced during certain types of vigorous physical activities stimulates formation of cam-type deformity. We further hypothesize that the growth plate shape modulates the influence of mechanical factors on the development of cam-type deformity.

Design

We used finite element (FE) models of the proximal femur with an open growth plate to study whether mechanical factors could explain the development of cam-type deformity in adolescents. Four different loading conditions (representing different types of physical activities) and three different levels of growth plate extension towards the femoral neck were considered. Mechanical stimuli at the tissue level were calculated by means of the osteogenic index (OI) for all loading conditions and growth plate shape variations.

Results

Loading conditions and growth plate shape influence the distribution of OI in hips with an open growth plate, thereby driving the development of cam-type deformity. In particular, specific types of loads experienced during physical activities and a larger growth plate extension towards the femoral neck increase the chance of cam-type deformity.

Conclusions

Specific loading patterns seem to stimulate the development of cam-type deformity by modifying the distribution of the mechanical stimulus. This is in line with recent clinical studies and reveals mechanobiological mechanisms that trigger the development of cam-type deformity. Avoiding these loading patterns during skeletal growth might be a potential preventative strategy for future hip OA.

Keywords

Cam femoroacetabular impingement
Etiology
Finite element method
Mechanical loading
Growth plate shape

Cited by (0)