Sacrum is derived from the Latin word os sacrum which means “sacred bone.” The word “sacred” is significant because it is the base of support for the entire upper body. In addition to that it also provides support for the spine, holds the spinal nerves, and connects with the hip bones to form the pelvis. The sacrum is located just below the lumbar spine and begins as 5 distinct vertebrae until it solidifies into a single bone between the ages of 18 and 30. Just beneath the sacrum is the coccyx, also known as the tailbone. It is made up of between one and three bones that are fused together, bears the body’s weight while sitting, plus provides an anchor for the muscles in the pelvic region.
Everything from the hips on down are the parts of the areas of the body that are controlled by the nerves in this region of the spine. There are symptoms associated with a problem in the sacrum and coccyx from pain when sitting, to hemorrhoids and itching in the same area. The sacrum plays a vital role in several systems in the human body: skeletal, muscular, nervous and female reproduction. In the skeletal system, the it is the cornerstone for the spine and hips. It connects key muscles in the legs and hips, giving the legs movement. With respect to the nervous system the sacrum and coccyx protect the nerves that control the lower extremities. And in a woman, the sacrum helps to form the pelvic cavity which supports and protects the fetus.
Fractures can occur in the sacrum. These fractures are known as sacral insufficiency fractures. These occur when the sacral bone is no longer able to handle the weight it carries. In older women, osteoporosis is the leading cause of sacral insufficiency fractures, but other risk factors include radiation to the pelvis, steroid use, rheumatoid arthritis, hyperparathyroidism, anorexia, and hip joint replacement. Surprisingly these fractures can also occur in pregnant or breast feeding women due to a condition known as temporary osteoporosis. Symptoms of this type of fracture include pain in the lower back, hips, groin, or pelvis area. Up until the early 80’s, sacral insufficiency fractures went undiagnosed. Treatment is non-surgical and requires rehabilitation therapy, electrical stimulation, and massage.