Comparative study of the
femoracetabular impingement (FAI) prevalence in male semiprofessional and
amateur soccer players

M, Walter PA, Pellengahr CS, Hagen M, von Engelhardt LV, & Lukas C.  Arch
Orthop Trauma Surg. 
2014 Published
Online First May 25, 2014: doi: 10.1007/s00402-014-2008-6

Take Home Message:  Male semiprofessional soccer athletes have a
higher prevalence of femoracetabular impingement (as measured by alpha angle)
than male amateur soccer athletes.

Femoracetabular impingement (FAI), specifically a cam-type
impingement, is a key risk factor for hip osteoarthritis.  FAI is common in young male elite that
participate in sports such as soccer, football, and ice hockey
that create excessive stress to the hips; however, it is unclear if amateur
athletes are also at risk for FAI.  The
authors of this study compared the presence of radiographic FAI in 44 male
soccer athletes (22 each semiprofessional level and amateur level) as well as
compared functional and clinical outcomes between the two groups.  Soccer athletes in both groups were 18 to 30
years of age. An orthopaedic surgeon and radiologist assessed the presence of
FAI by measuring the hip alpha angle on
magnetic resonance images that were acquired on both hips of each athlete.
Larger alpha angles are related to cam-type FAI. Semiprofessional soccer
athletes had larger alpha angles (57.3 degrees) in the hip of their kicking leg
than amateur soccer athletes (51.7 degrees). 
Furthermore, 63% of semiprofessional and 27% of amateur athletes had cam-type
FAI present in their kicking leg (alpha angle > 55).  Clinical and functional outcomes were similar
between groups; however, amateur soccer athletes scored better in the hip
outcomes sports subscale score and had less hip internal rotation bilaterally
than semiprofessional soccer athletes.  

findings affirm that FAI prevalence is high within a soccer population, and
that level of play may affect the predisposition to FAI, and ultimately, hip
osteoarthritis.  The repetitive kicking
motion that combines flexion and internal rotation may cause microtraumatic
wear that stimulates FAI development. 
While it would be interesting to follow these cohorts over time, it is
evident that there are differences despite the athletes being largely
asymptomatic.  Future studies could offer
more details about sport performance (e.g., kicking velocity).  Furthermore, we recently learned that FAI may develop while athletes are skeletally immature so it might be beneficial to not only classify athletes
based on their current skill level but also their skill level when they were
still maturing. Lastly the authors admit that a limitation to this study is
their use of standard magnetic resonance imaging as opposed to an arthrogram
that may tell us more about the prevalence of concomitant labral damage.  Clinically we need to decide what we should
do about this, perhaps addressing technique, limiting kicks, or determining if
there is anything that may be able to be done to intervene once the FAI is
detected.  It is evident that high-level
athletes are at risk, but we need to better understand how much and what type
of stress may be dangerous in skeletally maturing athletes so that we can
implement prevention programs to modify these risk factors.        

Questions for Discussion:  What
clinical modifications do you think might be necessary to prevent FAI in an
at-risk population?  Is there anything
that you are seeing done clinically that has helped with chronic hip pain?
by: Nicole Cattano
by: Jeffrey Driban

Related Posts:

Cam-Type Deformity in Adolescent and Young Male Soccer Players

Lahner, M., Walter, P., von Schulze Pellengahr, C., Hagen, M., von Engelhardt, L., & Lukas, C. (2014). Comparative study of the femoroacetabular impingement (FAI) prevalence in male semiprofessional and amateur soccer players Archives of Orthopaedic and Trauma Surgery DOI: 10.1007/s00402-014-2008-6