Triad for the diagnosis of the FAIS - all of the following:
(1) clinical symptoms
(2) findings on the clinical examination
(3) positive imaging findings
Clinical symptoms include:
(1)
motion or position related groin pain
(2) motion or position related lateral hip or buttock pain
(3) locking or catching
(4) clicking
(5) giving way
(6) restricted range of motion
(7) stiffness
The clinical exam may show:
(1) an abnormal gait
(2) reduced hip muscle strength
(3) variable change in range of motion, especially restricted internal rotation in flexion
(4) pain on hip impingement (flexion adduction internal rotation)
(5) pain relief with local anesthetic injection
Imaging studies may show:
(1) acetabular retroversion (pincer impingement refers to a deep or retroverted acetabulum)
(2) femoral retroversion
(3) increased lateral center edge angle
(4) cam deformity (aspherical femoral head or presence of additional bone at the femoral head-neck junction)
Any one of these features may be present without clinical progression to FAIS. All three need to be considered when making the diagnosis.
