If there are bumps on the left side of the neck, the following causes can be considered: First, if there are bumps on the front of the left side of the neck, it may be a local lymph node enlargement, or it may be a swelling of the thyroid gland, such as a thyroid adenoma, or a thyroid nodule, which can be checked at the hospital and a local ultrasound can be used to make a clear diagnosis. If the swelling is in the thyroid gland, the swelling can be seen on physical examination and can move up and down with swallowing. In addition, if it is on the posterior side of the neck, it may be a muscle strain or muscle inflammation leading to local inflammatory nodules, which may cause significant pain when pressed, and is also related to the movement of the cervical spine, which may appear or worsen when moving.