Groin pain

The differential diagnosis for groin pain is very broad and complex. Pain referred to the groin can be caused by traumatic injury to various intra-articular structures (cartilage, labral, osseous) or extra-articular tissues (muscle, tendon, bursa). The pain may be caused by common degenerative conditions, such as osteoarthritis, or anatomical and mechanical distortions seen in conditions such as femoroacetabular impingement or hip dysplasia. Additionally, pain may be referred from non-musculoskeletal areas, including the abdomen, genitourinary tract, and lumbar spine.

The cause of overuse lesions is not fully understood. Micro-lesions leading to degenerative changes or to chronic inflammation have been suggested. The lesion can be located in the muscle, the tendon, or the enthesis. The changes seen in the pubic bone and around the pubic symphysis probably reflect the amount of stress inflicted by the sport or activity involved, although these changes are not a definite sign of pathology but rather a sign of a repair reaction.[8]Branci S, Thorborg K, Bech BH, et al. MRI findings in soccer players with long-standing adductor-related groin pain and asymptomatic controls. Br J Sports Med. 2015;49:681-691. http://www.ncbi.nlm.nih.gov/pubmed/25512059?tool=bestpractice.com

In the hip joint, femoroacetabular impingement (FAI) can be caused by a variety of dysplasia especially related to the acetabulum, and by the so-called cam lesion, which is perhaps inflicted in puberty by excessive loads from sport. FAI and other types of trauma or overuse can lead to intra-articular lesions of the labrum, cartilage, or the ligamentum teres.

The Doha classification

In November 2014 a consensus meeting regarding the terminology of groin injuries in athletes was held, and the results were published in May 2015.[1]Weir A, Brukner P, Delahunt E, et al. Doha agreement meeting on terminology and definitions in groin pain in athletes. Br J Sports Med. 2015;49:768-774. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4484366 http://www.ncbi.nlm.nih.gov/pubmed/26031643?tool=bestpractice.com The outlines of the consensus classification are in principle followed in this topic.

1. Adductor-related groin pain

2. Iliopsoas-related groin pain

3. Inguinal-related groin pain

4. Pubic-related groin pain

5. Hip-related groin pain

6. Other musculoskeletal causes

   • Inguinal or femoral hernia

   • Post-hernioplasty pain

   • Nerve entrapment

   • Referred pain

   • Apophysitis or avulsion fracture

   • Spondyloarthropathies (e.g., ankylosing spondylitis).

7. Other causes

   • Inguinal lymphadenopathy

   • Intra-abdominal pathology (e.g., prostatitis, urinary tract infections, kidney stones, appendicitis, diverticulitis)

   • Gynaecological conditions

   • Tumours (e.g. testicular tumours, bone tumours, prostate cancer, urinary tract cancer, digestive tract cancers, soft-tissue tumours).

8. Congenital/anatomical

   • Slipped capital femoral epiphysis

   • Hip dysplasia

   • Femoroacetabular impingement.