Written By: Noor Rahim

One may hear about sciatica so often that they’re tempted to label any “shooting pain” from the back as sciatica. However, there are varied sources of pain that stem from the back and due to their different origins, the diagnosis and treatment may vary. As doulas, and more specifically support persons, for our to-be mothers, it is important we encourage clients that have recurring painful bodily pain to follow with a physical therapist who will accurately diagnose and create a suitable treatment plan.

Sciatica refers to pain that travels through the sciatica nerve from one’s lower back through one’s hips and buttocks and down each leg. It is the longest nerve in the body. Pain tends to arise in one area more than the other. Similarly the sacroiliac (SI) joint tends to also localize in one area more than the other but sciatica has a wider variation in range due the length of the nerve. The SI joint is located where the spine meets the pelvis and unlike a nerve, its main function is shock absorption for the upper body. Not only do their functions differ but their causes as well.

Whilst sciatica is caused by nerve compression, SI joint pain can be caused by varied conditions, including (for the more accurate purpose of our profession) the release of the hormone “relaxin” during pregnancy. This hormone enables the ligaments that support the SI joint to relax, thus creating flexibility which when paired with stress and instability from the growing fetus, causes dysfunction and weakness.

SI joint dysfunction commonly translates to pelvic floor weakness and limitations in the movements of the pelvic floor and hips. It can cause a sharp stabbing pain in the back that gets especially painful when weight is placed on one side more than the other. A weak pelvic floor can fail to stabilize the pelvis which leads to increased stress on SI joints. Whilst a weak pelvic floor can also cause sciatica, it is by the compression of the sciatic nerve due to surrounding overly tight muscles. Sciatica and SI joint pain can both cause numbness in the lower back, buttocks, legs, or feet. Pain can radiate from the lower back and down the legs but there’s potential for a greater range with sciatic than SI joint pain. Both conditions can cause difficulties with walking and burning or uncomfortable sensations that vary from person to person.

Certain treatments and techniques, such as the use of a supportive SI joint braces/belts and sacroiliac joint injections can be used to relieve SI joint pain but would not be of use for sciatica.

The hope is for us to look deeper into our recommendations for our clients the next time they complain of recurring bodily pain and to enable ourselves to direct them to proper resources.