Brian P. Jacob, David C. Chen, Bruce Ramshaw, Shirin Towfigh (eds.) - The SAGES Manual of Groin Pain-Springer International Publishing (2016)

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J.C. Campbell and G.D. Paiement
is very acute. Hip arthroplasty is an effective and reproducible procedure
but should be carefully weighed against the risks of the procedure.
Finnish Registry data suggest a 15-year revision-free survival rate of
71–86 % for total hip arthroplasty [ 6 ]. Not unlike other complex
procedures, outcomes are better when performed by high-volume
surgeons in high-volume centers .
Femoroacetabular Impingement
Presentation Femoroacetabular impingement (FAI) is a
developmental abnormality of either the femoral head-neck junction
and/or the acetabulum, either of which leads to abnormal hip function.
These patients are generally young and/or active. They fall into two
broad categories: cam-type impingement (loss of femoral head-neck
offset) and pincer-type impingement (acetabular over-coverage). These
biomechanical abnormalities lead to tears of the acetabular labrum
(discussed in the next section) and delamination of the cartilage. This is
theorized to be the precursor of the so-called idiopathic OA; however, it
is not yet clear if surgical intervention has any influence on development
of OA later in life [ 7 ].
Physical Exam Groin pain with anterior impingement is exacerbated
with high flexion, adduction, and internal rotation at the hip (Fig. 8.7 ).
Alternatively, posterior impingement is made worse with extension and
external rotation [ 1 ]. Either of these may be combined with or exclusively
present with labral-type symptoms, often with a popping and catching
sensation with motion, which causes pain.
Diagnostic Exams Low AP weight-bearing pelvis (including both
hips) with a supine lateral radiograph of the affected side (“frog leg
lateral”) is recommended. Radiographic measurements are taken to
assess for these abnormalities, as they are often subtle (Fig. 8.8 ).
Differential Cam-type impingement is classically described among
young athletic males. Given this population, it is important to rule out
muscular strain or even sports hernia . Femoral hernia should be
considered among women, even if pincer-type impingement is noted.
The strict definition of cam versus pincer type impringement is somewhat
of an oversimplification, however, with as much as 80 % of cases being
considered a combined mechanism [ 9 ].