Tension headaches are one of the most common types of headache. These headaches are so named because they often result from tension in the RCPM (rectus capitis posterior minor) muscle. When the RCPM muscle tightens, it pulls on a sensitive tissue at the base of the skull called the dura mater, which sets off a classic tension headache.
Stress, poor posture, and clenching of the jaw are all commonly seen in people who suffer from tension headaches. While anyone can have the odd tension headache, constant or recurring headaches may indicate a musculoskeletal misalignment in the upper cervical spine.