Learning objectives
The purpose of this poster was to summarize clinical and radiological basis of FAI,
highlighting those findings that can be commonly encountered in the daily clinical routine.
Background
Femoro-acetabular impingement (FAI) is a pathologic condition that was firstly described by Swiss orthopedic surgeon Reinhold Ganz [1],
that is frequently seen in young active subjects,
often in conjunction with top-level sport activities,
in which bony components of the hip joint do not match correctly.
This pathologic condition can be caused by an anomalous junction between femoral head and neck,
by an anomalous acetabular shape or orientation,
or by a various combination of both factors (this latter event is the most common,
occuring in up...
Imaging findings OR Procedure details
Aetiology
FAI is characterized by an abnormal contact of the bony components of the hip,
particularly during flexion and intra-rotation,
when the anterior aspect of the femoral head-neck junction hits the acetabulum,
thus reducing hip range of movement [1].
In this setting,
normal movements performed when an abnormal anatomic is present lead to an abnormal contact between articular surfaces,
then leading to relevant degenerative abnormalities [3].
The cause of this pathologic condition is mainly congenital [4].
FAI can be considered as one of the most...
Conclusion
FAI is a pathologic condition with multiple clinical and diagnostic aspects that affects the hip joint.
Clinical evaluation – that remains fundamental – must be associated to an imaging evaluation,
aimed to the detection of morphostructural abnormalities of this condition.
Since clinical indication for radiologic examinations of FAI patients is often non specific,
the general radiologist should be able to detect the typical abnormalities of such condition that,
if misdiagnosed,
may lead to early juvenile osteoarthritis.
References
Ganz R,
Parvizi J,
Beck M,
Leunig M,
Notzli H,
Siebenrock K (2003) Femoro-acetabular impingement: an important cause of early osteoarthritis of the hip.
Clin Orthop 417:112–120
Tannast M,
Siebenrock KA,
Anderson SE (2007) Femoroacetabular impingement: radiographic diagnosis-what the radiologist should know.
AJR Am J Roentgenol.
188:1540-1552
Leunig M,
Ganz R (2005) Femoroacetabular impingement: a common cause of hip complaints leading to arthrosis.
Unfallchirurg 108:9-17
Hoaglund FT,
Steinbach LS (2001) Primary osteoarthritis of the hip: etiology and epidemiology.
J Am Acad Orthop Surg 9:320-327
Tanzer...