URA Highlights

Diagnosing and Treating Groin Pain

Athletic groin pain can be a diagnostic and therapeutic challenge. While only 2-5% of athletic injuries occur in the groin region, these injuries are often more difficult to adequately treat and comprise a larger proportion of “time lost” for athletes than their incidence would suggest.

Diagnosing the cause of groin pain is problematic because of the large number of etiologies. Non-athletic causes of groin pain include a wide differential of intra-abdominal inflammatory entities, a traditional inguinal hernia and genitourinary abnormalities. Fortunately, many of these entities can be excluded by history and physical exam. However, the athletic causes of groin pain still present a wide differential which may be difficult to narrow without imaging.

If non-athletic causes of groin pain are felt to be less likely, a radiograph of the pelvis should be performed to evaluate for hip DJD, osteitis pubis or evidence of stress fracture. However, a patient usually will be symptomatic for quite some time before radiographic manifestations are evident.

If radiographs are not helpful, MRI of the hip should be considered. MRI is much more sensitive for early stress fracture, stress-related osseous change, and early degenerative change. If internal derangement of the hip is suspected, MR arthrography should be considered for optimal evaluation of the acetabular labrum.

Various soft tissue abnormalities may also contribute to athletic groin pain. For example, adductor dysfunction may be a cause of pain only appreciated by MRI. A symptomatic combination of early symphysis pubis inflammation related to adductor dysfunction may give rise to the MRI “secondary cleft sign,” and this suggests that the patient may benefit from symphyseal steroid administration (see secondary cleft image on next page). Iliopsoas bursitis as well as hip rotator cuff or hamstring musculotendinous injuries will also be demonstrated by MRI.

There are several other diagnoses to consider after negative MRI examinations of the hip and pelvis. Non-ingunal abdominal wall or rectus abdominus muscular hernias are extremely difficult to diagnose clinically or by MRI. Ultrasound may show these entities dynamically if they are suspected.

A diagnosis of exclusion to consider is the “sports hernia.” This term is used several ways in the literature, but recent “sports hernia” literature focuses on a specific weakness of the posterior wall of the inguinal canal, especially at the external ring. It is felt to be caused by an imbalance between axial/abdominal wall muscle strength and lower extremity muscle strength (especially adductors). This etiology is proposed because this injury commonly arises early in the sport season, and it is surmised that athletes continue off-season lower extremity strength training without commensurate strengthening of the axial/abdominal wall musculature.

Regardless of the etiology, the patient presents with pain mimicking an inguinal hernia, but no hernia is detected on clinical exam or on imaging. However, patients with “sports hernias” have been successfully managed surgically with mesh repair similar to traditional inguinal hernia repair with good results.