The small joint that rests where the spine and the pelvis meet is called the sacroiliac joint. Typically, when we hear the word “joint” in reference to the human anatomy, we think of elbows, knees, hips, and shoulders, as these are the areas that create motion. Even though the sacroiliac joint does not move significantly, it has tremendous impact on how the upper body load is transferred to the lower body.
It can be difficult to diagnose pain in the sacroiliac joint because this joint is not easily manipulated or touched. Diagnostic results of this joint typically return as normal, as tests cannot simply isolate this joint. Also, a host of other problems, such as back pain, sciatica, and hip arthritis, can create similar symptoms.
The causes of sacroiliac joint pain and injury can be brought on by trauma. For example, a person could land on his or her buttocks with such force that damage is sustained to the ligaments that support the sacroiliac joint. Another cause could be biomechanical in nature, due to muscle imbalance, overpronation, or leg length discrepancy. Pregnancy, with the added stress it puts on the spine through weight gain, can contribute to sacroiliac joint injury and pain.
Some of the symptoms of this type of injury include noticeable pain when turning over in bed. When putting on socks and shoes, the patient might notice discomfort in the lower back. Getting one’s legs out of a car may prove to be painful and difficult. When driving for an appreciable amount of time, one may notice significant pain to either side of the back.
A good initial method of diagnosing any problem with the sacroiliac joint is to simply feel for it and see if it is tender. The FABER test, which places pressure across the joint, can indicate any potential problem. This is done with the patient lying down, flexing the hip, abducting the leg, and rotating the hip externally. This particular movement will place pressure right across the sacroiliac joint.
If that particular diagnosis is inconclusive, then an injection of a numbing agent, such as Novocain, can be administered into the sacroiliac joint.