A Cam Deformity Is Gradually
Acquired During Skeletal Maturation in Adolescent and Young Male Soccer
Players: A Prospective Study With Minimum 2-Year Follow-up.

Agricola
R, Heijboer MP, Ginai AZ, Roels P, Zadpoor AA, Verhaar JA, Weinans H, &
Waarsing JH.  Am J Sports Med.  2014
Published Online First Feburary 28, 2014: doi: 10.1177/0363546514524364

Take Home Message:  Cam deformities develop over time in
skeletally immature elite soccer athletes.

A
cam deformity
may increase a person’s risk for chondral or labral hip injuries, and
ultimately hip osteoarthritis (OA).  Athletes
in high-impact sports are more likely to have of cam deformities compared with
nonathletes (see related posts below). 
Cam deformities may develop in response to high-impact sports during
growth but it remains unclear as to how these deformities progress among
athletes during and after skeletal maturity. 
Therefore, the authors of this study primarily assessed how a cam
deformity develops among adolescents and if the formation of this deformity is
primarily before skeletal maturity. Sixty-three elite adolescent soccer
athletes (12 to 19 years of age) received bilateral hip x-rays at baseline and
at a 2 year follow up.  Skeletally immature
athletes were more likely to develop a cam deformity or progress than older
athletes. Among the 22 younger aged soccer players (12 or 13 years, 44 hips)
the number of normal radiographic hips decreased from 84% at baseline to 43% at
follow-up.  In comparison, among the 24
athletes, who were between 14 and 15 years of age, 31% of hips had normal hip
radiographs at baseline but only 17% did at follow-up. Among the 17 athletes
over 16 years of age 35% had normal hip radiographs at baseline and follow-up.
When the authors examined the 96 hips with open growth plates, 57% had normal
radiographs at baseline but only 31% were still normal two years later. In
contrast, among the 30 hips with closed growth plates 30% had normal hip
radiographs at baseline and follow-up. Limited hip internal rotation as well as
small neck shaft angle may be predictive of cam deformity formation.

This
is one of the first studies to look over time at cam deformity formation and
progression within an at-risk population of elite soccer players.  The study supports previous claims that
athletes in high-impact sports and who are still growing may be at risk for cam
deformities. There are a few key clinical factors that we may be able to focus
on such as internal rotation deficits to help aid in the prevention of cam
deformity formation.  Internal rotation
deficits are focused on tremendously within the shoulder, and these findings
support that we may need to investigate this clinical measure within the hip
joint.  Unfortunately, we do not know
what caused the hip internal rotation deficits (i.e., bony vs. soft tissue) nor
do we know if an intervention like stretching would be successful in improving
range of motion.  While these findings
are interesting, we need to investigate whether these results would be similar among
non-elite athletes who participate in the same at-risk sport.  Without this additional information we do not
know if we can apply these findings to non-elite athletes.  This is an important question because cam
deformities with internal rotation deficits are strongly associated with hip OA.
 Early intervention may be key because once
radiographic changes start to occur in OA there is little that we can do to
reverse the degenerative changes.  As
clinicians we may be able to start to investigate activity modification during
vulnerable skeletal maturity times as well as emphasize clinical factors that
we can modify (i.e., hip internal rotation deficits) to try to help prevent cam
deformity development. However, if the internal rotation deficit is a result of
bony adaptation, we may need to look even earlier in the process.  These findings identify prospects for future
research and may help in the early prevention of hip OA development.  


Questions for Discussion:  Do
you think that activity modification for the hip is a reasonable recommendation
among skeletally immature athletes?  If
yes, what modifications might you recommend? What have you seen clinically that
aids with generalized hip pain or hip internal rotation deficits? Have you
noticed hip internal rotation deficits among young athletes?
    
Written
by: Nicole Cattano
Reviewed
by: Jeffrey Driban

Related Posts:


Agricola, R., Heijboer, M., Ginai, A., Roels, P., Zadpoor, A., Verhaar, J., Weinans, H., & Waarsing, J. (2014). A Cam Deformity Is Gradually Acquired During Skeletal Maturation in Adolescent and Young Male Soccer Players: A Prospective Study With Minimum 2-Year Follow-up The American Journal of Sports Medicine DOI: 10.1177/0363546514524364