Adductor Strain

Groin issues make up about 2-5% of all athletic injuries. Groin pain can become challenging because it has a high recurrence and has lingering symptoms. The most common groin injury is a strain to the adductor muscles.

What is it

The adductor muscles function to approximate the thigh in open chain motions and they stabilize the pelvis during closed chain activities. The adductor group is also used to generate substantial force during complex athletic movements.

Injuries most often occur during explosive actions that require the adductors to contract eccentrically.

Chronic adductor issues are caused from repetitive stress to the area during activity and leads to more proximal hip irritation. Acute injuries occur most commonly at the musculotendinous junction and rarely occur at the muscle belly. Complete ruptures are rare.

There is a grading system for groin strains that range from grade 1 to grade 3. Grade 1 is when there is some pain in the area but has minimal loss of mobility or strength. Grade 2 includes pain along with loss of strength and function. Finally, a grade 3 is when there is a complete tear of the muscle/tendon which is accompanied by no function.

Some predisposing factors for groin strains include a history of prior injury or inadequate physical conditioning. Injuries are seen more commonly in sports requiring forceful eccentric adductor contraction, such as kicking, sprinting, forceful trunk rotation, and side-to-side cutting.

Symptoms

The chief complaint of an adductor strain includes pain on the proximal inner thigh that radiates distally and is provoked through movement. Symptoms are exacerbated when the muscle involved is stretched or when contracted eccentrically during a sports movement.

While grade 1 strain produces minimal pain and disability, more severe strains/ grade three can lead to intense pain and complete loss of function. Acute tears often cause an immediate functional deficit, whereas chronic stress injuries lead to a more gradual reduction in function.

During a clinician evaluation of a groin strain there will be tenderness when palpating over the proximal inner thigh. In addition, there will be pain with passive abduction and/or resisted adduction.

Also, during the clinician evaluation there should be an assessment of the lumbar spine, sacroiliac joints, and hips to identify concurrent or alternate pathology. There may be some functional deficits that compromise hip stability and contribute to groin pain which include hyperpronation, lower cross syndrome, and gluteus medius weakness.

Diagnosis

A clinical evaluation is the gold standard for diagnosing an adductor strain. However, if the clinician believes there is any tendon avulsion or bony pathology, a radiography may be ordered. If bony pathology is not suspected, an ultrasound may be a better option for imagery. If necessary, an MRI may be appropriate to find a lesion and rule out alternative diagnoses.