There is a tendon in the neck that hurts, and the following causative factors may exist: First, the effect of trauma. For example, direct violent blows, or indirect violent pulling, can cause muscle strains and inflammation in the neck, thus producing pain. Second, the influence of cold. Cold can cause muscle spasm and aseptic inflammation. Third, the effect of exertion. Exertion can cause the deposition of lactic acid in the muscles, thus producing pain. Fourth, the impact of bad posture. Some bad posture, such as long-term sitting and standing, head down, or bad sleeping posture, can lead to muscle spasm, thus generating pain. Fifth, the impact of cervical spondylosis. If local muscle spasm is produced, or compression of nerve roots, producing radiating pain in the neck and shoulder area, it may also produce similar symptoms.