Muscle pain around the clavicle may be caused by the following reasons: 1. It may be caused by some bad posture. It is common for patients to lie on their side for a long time, or to fix their shoulders and neck in a certain position for a long time. This may cause excessive fatigue or even spasm of the muscles around the clavicle, which may lead to pain here. 2. It may be caused by trauma to the muscles here. For example, a direct violent blow to this part, or a violent pull or twisting of the patient’s upper limb and neck, may cause strain on the muscles and tendons here, which may cause pain. 3, may be caused by cold in this part. The patient may have been exposed to cold wind during sleep, which may cause muscle spasm and pain. 4. When the patient is very nervous, some of the muscles around the clavicle may be continuously tense, such as the oblique muscle, sternocleidomastoid muscle or pectoralis major muscle muscle spasm, resulting in pain here.