Groin pain is most commonly associated with pulled muscles, specifically the adductor muscle. However, some causes of groin pain may have nothing to do with any of the muscles or bones in the groin area. Pain in the groin area may be caused by problems in the Sacroiliac joint in the lower back.
The Sacroiliac joint is the joint that lies between the sacrum, a triangular bone at the base of the spine, and the ilea, two bones on either side of the pelvis. The joint is held together with strong ligaments, and can be subject to strain. There are two of these joints, on either side of the pelvis, and these joints are weight bearing. This important joint supports the entire weight of the body when we are standing upright. The joint is considered immovable because it is held together with strong ligaments, but it is still subject to movement forces. The Sacroiliac joint is designed to help prevent the force of movement from activities like twisting, walking, and running, from impacting the spine.
When the joint is injured, either by ligament strain or fracture, it causes mild to intense lower back pain. However, sometimes the lower back pain located at the site of the Sacroiliac joint can be felt in other places, like the legs or the groin. It is called referred pain when pain occurs away from the site of the original injury. Though there are several theories as to what causes referred pain, the phenomena, while clearly noted in medical literature, is not fully understood.
The groin pain caused by referred pain from a Sacroiliac joint injury can be chronic or acute, as the pain may not always be the same from day to day, as well as manifesting in other places, like the lower back and the legs. Diagnosing pain associated with the Sacroiliac joint is often difficult because the joint is hard to palpate and does not move easily. When a patient presents with groin pain, pulled muscles or hernias are often the first line of inquiry, but when these more common avenues are exhausted, a closer look at the Sacroiliac joint may reveal the cause of pain.
Sacroiliac joint injuries are most often caused by falls or car accidents. Anything that causes the ligaments in the Sacroiliac joint to stretch can cause movement in the joint, resulting in pain. However, there are other causes as well. People born with an abnormally shaped sacrum may experience degeneration in the Sacroiliac joint. Childbirth can also cause problems in the Sacroiliac joint, as labor can over-stretch the ligaments in the Sacroiliac joint. Unusual walking patterns and leg length discrepancies, as well as arthritic diseases can also lead to problems in the Sacroiliac joint.
Groin pain caused by damage to the Sacroiliac joint can be treated in a number of ways. Some pain may respond to non-steroidal anti-inflammatory drugs. In more severe cases of pain, steroids and narcotic drugs may be used. If the groin pain is chronic, physical therapy may be recommended. The most severe cases may require pain and steroid injections directly into the Sacroiliac joint. Surgery may also be required in the worst cases.