Pelvic sacral blocks are simple, wedge-shaped tools, typically made of firm foam or wood, designed to assist in gentle, gravity-assisted alignment of the pelvis. They function as a non-invasive method, using the body’s own weight to create mild leverage on the pelvic structures. The purpose of using these blocks is to facilitate relaxation in the musculature and ligaments surrounding the sacroiliac (SI) joints and the lower back. This technique is intended to support the body in moving toward a more balanced pelvic position.
Understanding How Pelvic Blocks Work
Pelvic blocks operate on the principle of using a person’s body weight and gravity to apply sustained, mild pressure to specific points on the pelvis. When a person lies on the blocks, the wedges lift and support the ilium (the large, upper part of the hip bone) or the sacrum (the triangular bone at the base of the spine). This strategic positioning creates leverage that encourages the gentle unwinding of soft tissues and the release of tension in the sacroiliac joint. This gentle approach relies on sustained positioning to facilitate change over time, differing from more forceful adjustments.
The primary goal is to encourage the muscles surrounding the SI joint to relax, which can help the pelvis shift toward a more balanced state. Misalignment in the SI joint can sometimes cause strain on surrounding muscles and nerves, leading to lower back discomfort or sciatica. By holding the pelvis in a specific, supported position, the blocks allow the body’s natural forces to reduce pressure on the joint and surrounding structures.
Essential Safety Rules Before Use
Before incorporating pelvic blocks into a home routine, it is important to understand that they are a positional tool, not a substitute for professional medical care. Consulting with a chiropractor or physical therapist is highly recommended to confirm the technique is appropriate for your specific condition and to receive personalized placement instructions. A professional can correctly determine the pattern of pelvic misalignment, which is necessary for proper block placement.
Contraindications
Certain conditions are considered contraindications, meaning the blocks should not be used. These include:
- Acute, severe low back or pelvic pain.
- Recent trauma or injury to the area.
- The presence of specific spinal hardware.
- Advanced stages of pregnancy.
It is important to stop immediately and seek medical advice if the use of the blocks causes sharp or increasing pain.
The surface on which the blocks are used must be firm and flat, such as a yoga mat on the floor, as a soft mattress will absorb the leverage and prevent the technique from working effectively. Always maintain a neutral and relaxed position while on the blocks, avoiding any active straining or aggressive movements.
Step-by-Step Guide to Block Placement
To begin, lie down on your back on a firm, flat surface with your knees bent and feet flat on the floor, which helps to relax the lower back muscles. The specific placement of the blocks depends on the intended adjustment, which ideally should be determined by a healthcare provider. For general, bilateral home use, a common starting position involves placing the blocks under the posterior superior iliac spine (PSIS), which is the bony dimple at the back of the hip, or slightly lower under the greater trochanter.
One block is typically positioned under the ilium on one side, and the other is placed under the opposite ilium, or sometimes the sacrum, depending on the goal. The wedges are usually placed with the wide, thick edge facing outward toward the sides of the body and the thinner edge pointing inward toward the midline. This orientation allows the block to gently lift the targeted area of the pelvis.
To place the blocks, gently lift the pelvis and slide the wedges into the predetermined positions. The flat, largest surface of the wedge should be the part contacting the body. Once positioned, slowly lower your weight onto the blocks, allowing gravity to take effect.
Remain in a completely relaxed state with your knees bent or gently resting together, allowing your muscles to release tension around the blocks. Movement onto and off the blocks should be slow and deliberate to prevent sudden strain on the pelvic joints. The strategic placement creates a mild, sustained force that helps to normalize the position of the pelvis.
Recommended Session Duration and Post-Use
The recommended duration for a single session on pelvic blocks typically begins very short, around five minutes, and gradually increases as the body adapts to the support. Users often work up to remaining on the blocks for a maximum of 10 to 20 minutes per session. Consistency is more beneficial than excessive duration, so frequent, shorter sessions are advised.
During the session, it is normal to feel a mild, comfortable stretch or a sense of release in the lower back or hips as the muscles begin to relax. Any sensation of sharp, shooting, or increasing pain is a sign to immediately and carefully remove the blocks and discontinue use. When the session is complete, slowly roll off the blocks to the side rather than sitting straight up, which avoids sudden compression of the spine.
After removing the blocks, it is beneficial to rest for a few minutes on the floor before standing up. This brief rest period allows the body to integrate the positional changes that occurred while on the blocks. Following a session, avoid strenuous activities and instead opt for gentle movements, such as a short, slow walk, to allow the body to adjust to the improved pelvic alignment.