The human coccyx is composed of 3-5 individual segments or coccygeal vertebrae. Coccyx pain commonly results from trauma such as a fall or a direct blow during contact sports. This type of injury can result in a fracture or dislocation of the sacrococcygeal joint causing abnormal movement during sitting and significant pain. Most cases are associated with abnormal mobility of the coccyx, which may trigger a chronic inflammatory process leading to degeneration of articular cartilage at the sacrococcygeal joint. Coccydynia is seen in bike riders, rowers and computer junkies due to prolonged compression of the joint and surrounding neural structures.
In humans, the coccyx serves important biomechanical functions and is an attachment site for various muscles, tendons, and ligaments. Muscles inserting on the anterior coccyx include the levator ani, which is sometimes considered as several separate muscle parts, including the coccygeus, iliococcygeus, and pubococcygeus muscles. This important muscle group supports the pelvic floor (preventing inferior sagging of the intrapelvic contents), plays a role in maintaining fecal continence, and aids in proper diaphragmatic breathing. Muscles originating on the posterior coccyx include the gluteus maximus and strands of biceps femoris, which is often continuous with the sacrotuberous ligaments.
The coccyx serves somewhat as a weight-bearing structure when a person is seated. In a fully functioning body, the coccyx acts as a shock absorber by flexing forward during sitting, thus completing the tripod of weight bearing composed of the coccyx and the bilateral ischial tuberosities. The coccyx bears more weight when the seated person is leaning backward; therefore, many clients with coccydynia sit leaning forward.
Typical symptoms to check during the assessment phase:
- severe localized pain in the coccyx region
- visible bruising in the coccyx region
- pain upon sitting and/or direct pressure to the coccyx
- pain moving from sitting to standing
- pain during bowel movements or straining
- pain during sexual intercourse.
Manual therapy can be used as a conservative treatment for a coccyx injury by aiming to relax and extend the muscles in the area. Once musculofascial balance is restored to the pelvic bowl and lumbar spine, the therapist can use ligaments as levers to help move the coccyx back into a correct position. This can be done in a sitting, prone or side-lying position. The therapist begins by palpating the coccyx and pulling the attached ligaments in a posterior direction. After holding for a period of 10-60 seconds the tissues surrounding the coccyx should begin to release. A contract-relax method can be used in conjunction with this technique. As the coccyx is pulled posterior, the client is asked to do a gentle contraction of the pelvic floor muscles for 3-5 seconds. Upon relaxation, the coccyx can be moved further posterior.