Functional
Testing Provides Unique Insights into the Pathomechanics of Femoroacetabular
Impingement and an Objective Basis for Evaluating Treatment Outcome

Rylander J, Shu B, Favre
J, Safran M, Andriacchi T.  J Orthop Res
2013 Apr 26 [Epub ahead of print]

Take
Home Message: Objective measurements may provide added perspective to the
rehabilitation of femoroacetabular impingement not otherwise measured by
self-report surveys and clinical passive range of motion.

Femoroacetabular
impingement (FAI) is very common in some sports and can affect not only
athletic activity but also activities of daily living.  Despite functional impairments, we often
evaluate the success of a treatment for FAI not with functional assessments but
with just patient-reported pain levels and activity scales, post-surgical
femoral head and acetabular rim shape, and clinical passive range-of-motion
measurements. If we can develop new functional assessments to monitor FAI then
this may improve our current treatment strategies.  Rylander et. al. used 3-dimensional motion
capture techniques to measure walking and stair climbing among 17 patients
diagnosed with FAI prior to surgery and 1 year post-operatively.  The authors also evaluated 17 age-, gender-,
body mass index-matched volunteers, who reported no history of hip pain or
lower extremity injury (assessed at one time point). The primary outcomes were
active hip and pelvis range of motion during walking and stair climbing.  Pre-operatively, patients with FAI had abnormal
hip and pelvic kinematics during walking (i.e., reduced hip flexion, internal
rotation, and abduction) and stair climbing (i.e., reduced hip extension and
internal rotation but increased pelvic anterior tilt and rotation) compared with
healthy volunteers. At one year after surgery, patients with FAI improved their
range of motion for walking, but not for stair climbing.  Over time, patients after surgery improved their
hip flexion and internal rotation during walking but not hip abduction.  The authors found no hip or pelvic motion differences
between pre- and post-surgery during stair climbing.  However, despite the lack of changes in
kinematic profile, 16 of 17 patients reported decreased pain in the surgical
limb.

These results suggest
that surgery may improve patient-reported outcomes and hip range of motion
during walking but not during more challenging tasks (e.g., stair climbing). The
lack of post-operative changes in hip and pelvic range of motion during stair
climbing show that something other than the abnormal morphology that is addressed
during surgery may contribute to the kinematic differences noted in FAI
patients. This could be other structural abnormalities that are not addressed
in surgery or evidence that we need to further optimize our rehabilitation
strategies. Post-operative rehabilitation may play a large role in the full
recovery of patients with symptomatic FAI. 
It is important to address all angles of rehabilitation, as partial
recovery may lead to reinjury, re-occurrence of pain, and/or osteoarthritis.

Questions
for Discussion: How, or will, these results guide your approach to treating FAI
patients?  Are these deficits able to be
addressed through rehabilitation?

Written by:  Meghan Maume Miller
Reviewed by: Jeffrey
Driban

Related Posts:

Rylander, J., Shu, B., Favre, J., Safran, M., & Andriacchi, T. (2013). Functional Testing Provides Unique Insights Into the Pathomechanics of Femoroacetabular Impingement and an Objective Basis for Evaluating Treatment Outcome Journal of Orthopaedic Research DOI: 10.1002/jor.22375