The sacral Iliac (SI) joints join the lower part of the spine (sacrum) to the pelvis (iliac bones). There are two SI joints (right and left sides). The sacroiliac joints are encircled by a fibrous capsule and is stabilized with several strong ligaments. The main function of the joints is to bear the weight of the skeleton and transfer it to the hip bones. The weight can then be distributed to the two femurs in the standing position, or the ischial (sit) bones in the seated position. The sacroiliac joints allows little to no movement, however the movement that does occur are a gliding and rotatory motion. The rotatory movements of the sacroiliac joint are described as nutation and counternutation.

Causes of Sacral Iliac Pain:

Some potential causes of sacroiliac pain include arthritis, traumatic injury (fall), repetitive impact activities, pregnancy and post-partum states. Other potential contributors include spinal scoliosis, leg length discrepancy, and previous lumbar spine fusions. Sacroiliac pain can be aggravated with prolonged sitting or standing, standing on one leg, stair climbing, going from sit to stand, taking long strides, and with running.

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Symptoms of Sacral iliac pain:

Sacroiliac joint pain can be dull or sharp. It can also present as a stiffness. It is most commonly felt in the low back and buttock but can also be referred into the thigh or down the back of the leg.

How can a Physical Therapist help in the reduction of sacral iliac pain?

Physical Therapists can evaluate the position of the Si joints/pelvis and assess for any abnormal rotations/positions of the pelvis which can be contributing to the pain. It is common there is a leg length difference that either is causing additional irritation or is a result of the rotation also then contributing to the pain. Exercises for improvement in range of motion, flexibility/stretching and strengthening to the core muscles will all assist in a reduction/elimination to the pain.