The coccyx, commonly known as the tailbone, is a small, triangular bone located at the very bottom of the vertebral column, just below the sacrum. It is composed of three to five small, fused or semi-fused vertebrae. Its location makes it highly susceptible to injury from falls or direct trauma. A person can live without a tailbone.
The Current Biological Function of the Tailbone
The coccyx provides an attachment site for a network of tendons, ligaments, and muscles that make up the pelvic floor. These soft tissues, including portions of the large gluteus maximus muscle and the levator ani muscle group, anchor to the coccyx, helping to support the pelvic organs.
The coccyx also plays a role in weight distribution when a person is sitting down. It functions as one point of a three-part support structure, or “tripod,” alongside the ischial tuberosities (the sitting bones). When a person leans slightly backward while seated, the coccyx helps to absorb and distribute the body’s weight, providing stability and balance.
Is the Coccyx Essential for Survival?
The coccyx is not considered an essential structure for life or mobility in modern humans. It is classified as a vestigial structure, an evolutionary remnant of the tail that was present in distant ancestors. The remaining coccyx no longer serves the original purpose of balance and locomotion.
The body ensures that the functions the coccyx supports are backed up by stronger, surrounding structures. The muscles that attach to the coccyx have multiple, redundant attachment points on other bones of the pelvis. These alternative anchor points are more stable than the coccygeal vertebrae itself.
Because the coccyx is positioned at the end of the spinal column and does not house the spinal cord, its removal does not impact the nervous system’s ability to transmit signals. The integrity and stability of the pelvis and spine are maintained by the large, fused sacrum and strong ligaments. While its absence may require the body to adjust its mechanics, it does not compromise the ability to walk or perform daily activities.
Living Without the Tailbone
Surgical removal of the coccyx, a procedure known as coccygectomy, is performed when chronic pain cannot be resolved by conservative treatments. Recovery is lengthy, with initial healing taking several weeks. Most patients resume light activity within four to six weeks, but full recovery can take three months to a full year.
Sitting is the most difficult activity during the early recovery phase, and patients rely on specialized cushions to avoid pressure on the surgical site. Patients are allowed to mobilize and sit as much as they can tolerate. In the long term, most patients who undergo the procedure for chronic pain report significant relief and have an excellent prognosis. The body adapts to the loss of the bone, and patients experience no long-term functional impairment concerning walking or regular physical activities.