The sacro-iliac joint (SIJ) is a joint at the bottom of your back whereby the spine joins to the pelvis. There is an SIJ on each side of the sacrum where it joins onto the ilium (pelvis bone). It is thought to be a significant contributor to low back pain, particularly in the younger population.
The SIJ does have a bony locking mechanism but is very reliant on strong ligament structures to help support it. As with all soft tissue injures, i.e. injuries to tendons, ligaments, muscles etc, these tissues can be overloaded and produce a painful response. This is common in pregnancy when extra load in front can cause an extra load on these ligaments, or a trauma to the area.
There is very little movement in this joint and it is known that as we get holder, the movement lessens to a point where the bones fuse and no further movement comes from the joint.
Pain is often local to the joint and around the dimples in the lower part of the back. Pain can refer into the buttock and back of the thigh. Pain is often worse with movement and activities such as walking, climbing stairs and leaning forward can be sore. Pain is often eased with rest but being in one position for too long can also cause the area to become painful and gentle movement often helps alleviate the pain.
As well as the ligaments, the area is also very dependent on strength in key muscles around the area such as the glutes, abdominals and the hamstrings. Often, weakness in these muscles can overload the ligaments and cause them to become sore. Treatment therefore is often aimed at strengthening these muscles and your Physiotherapist at Pure will give you an exercise programme aimed at strengthening around the trunk and top of your legs. They may also discuss with you how to modify some of the activities that are causing the pain for a period of time until the pain has settled.
They may also suggest an SIJ belt that can help alleviate some of the symptoms short term whilst you are working on strengthening the muscles. It is important to say that this is not a long-term solution but may give you some comfort until the muscles have a chance to get stronger. These can often be helpful in the second and third trimester of pregnancy.
Your Physiotherapist at Pure may also suggest other treatment modalities such as manual therapy and acupuncture to help with the pain if they think it is appropriate and these can be a very useful adjunct alongside your exercise programme.
Here are some helpful exercises that you may find helpful to manage your SIJ dysfunction: