Sitting correctly can prevent and help SI. A person should sit with their back straight and feet on the floor, taking regular breaks to stretch. Choosing an ergonomic chair is also beneficial.

The sacroiliac (SI) joints are stabilizing joints that lie on either side of the sacrum and connect to the iliac bones of the pelvis.

The function of the SI joint is to absorb shock and allow load transfers between the spine and lower extremities. Strong muscles and ligaments surrounding the SI joint provide support and stability while allowing minimal movement. Tight, stiff, and weak muscles may lead to inflammation and pain in this region.

Long periods of sitting can lead to SI joint pain and intensify existing pain. Often, pain occurs in the low back, buttocks, and thighs.

Read on to learn how to minimize SI joint pain by sitting correctly, performing chair exercises, and selecting a suitable chair.

Best seating positions with SI painShare on Pinterest
Illustrated by Jason Hoffman

It is important for people to maintain proper posture and alignment to protect the SI joint and prevent pain — especially when sitting for extended periods. A person should continually check in with posture and make adjustments as necessary.

To sit in a chair:

  1. Sit on the sit bones.
  2. Position the hips level with the knees or slightly higher.
  3. Place feet flat on the floor, hip-width apart.
  4. Position the knees in line with or slightly wider than the hips.
  5. Elongate the spine and relax the shoulders.
  6. Lift the chest upward.
  7. Evenly distribute weight between both sides of the body.
  8. Place a lumbar cushion or rolled towel behind the lower back.
  9. Rest the back against the back of the chair.
  10. A footrest to support the feet is optional.

Keep reading about the seated position and back health.

Avoid:

  • allowing the knees to cross the midline
  • placing the knee over the thigh of the opposite leg
  • leaning, rotating, or twisting to one side

To sit in a car:

  1. Adjust the seat to an upright position, so the spine is straight.
  2. Adjust the seat height so the hips are level with the knees or slightly higher.
  3. Maintain a slight bend in the knees.
  4. Do not allow the backs of the knees to touch the car seat.
  5. Position the lumbar support in the curve of the lower back.
  6. Position the headrest behind the middle of the head.

To sit on the floor:

  1. Come into a kneeling position.
  2. Place the thighs on or between the calves.
  3. A cushion under the hips is optional.
  4. Sink back slightly and root into the sitting bones.
  5. Lengthen the spine and open the chest.

Chair exercises help prevent and alleviate SI joint pain by building strength, improving stability, and easing muscle stiffness.

A person should get up from sitting at least once per hour to move around and perform exercises.

Knee to chest

  1. Sit at the edge of the chair.
  2. Press the right foot firmly into the floor.
  3. Interlace fingers around the left knee.
  4. Draw the knee into the chest.
  5. Hold for up to 1 minute.
  6. Repeat on the opposite side.

Seated figure four

  1. Sit at the edge of the chair.
  2. Press the right foot firmly into the floor.
  3. Lift the left foot and place the outer ankle over the right knee.
  4. Gently lean forward.
  5. Keep the spine straight.
  6. Hold for up to 1 minute.
  7. Repeat on the opposite side.

Seated cat cow

  1. Press the feet firmly into the floor.
  2. Place the hands on the thighs.
  3. On an inhale, arch the spine, open the chest, and gaze upward.
  4. On an exhale, round the spine and draw the chin to the chest.
  5. Continue this movement for up to 1 minute.

Inner thigh activation

  1. Press the feet firmly into the floor.
  2. Place a block, pillow, or ball between the knees.
  3. Squeeze the legs together to activate the inner thighs.

Spinal twists

  1. Sit at the edge of the chair.
  2. Press the right foot firmly into the floor.
  3. Lengthen the spine and root into the sitting bones.
  4. On an exhale, twist to the left, starting from the base of the spine.
  5. If possible, allow the hips to face forward.
  6. Hold for up to 1 minute.
  7. Repeat on the opposite side.

Learn more about stretches and exercises for SI joint pain.

An ergonomic chair is essential to encourage proper posture and prevent SI joint pain.

Features to consider include:

  • Adjustable seat: Some chairs offer options to adjust the seat height, depth, and tilt to suit different bodies and workspaces.
  • Adjustable armrest: Position the armrests so the wrists are level with or slightly lower than the elbows.
  • Lumbar support: A cushion helps maintain the spine’s natural curve and encourages good posture.

Maintaining good posture helps to strengthen the muscles surrounding the SI joint and minimize pain. It is important for people to be aware of posture while standing, sitting, and performing activities. The following tips may help:

  • placing the feet hip-width apart or slightly wider to reduce low back tension
  • pointing the toes forward or slightly outward
  • distributing weight evenly between both sides of the body
  • maintaining a slight bend in the knees
  • keeping hips neutral and symmetrical to maintain pelvic alignment
  • engaging the abdominal muscles
  • keeping the chest broad and drawing the shoulder blades down
  • relaxing the neck and shoulders
  • maintaining a moderate weight
  • exercising regularly

The SI joints act as shock absorbers that help to stabilize the body and distribute the weight from the upper body to the lower limbs.

Injuries, poor alignment, and sitting for long periods can cause and exacerbate SI joint pain.

To prevent SI joint pain, it is vital for a person to improve posture, select a supportive, comfortable chair, and take regular movement breaks during seated activities.

People should also exercise regularly and perform stretches and other exercises to alleviate SI joint pain.