The splenius capitis muscle can contribute to pain at the top of the head and occasionally cause blurred vision. The muscle is affected by whiplash injuries.
forward head posture
The levator scapulae connect the shoulder blade to the vertebra of the neck. The muscle contributes to pain in the shoulder, neck, and the base of the skull. The muscle causes a stiff neck. It can contribute to headaches at the base of the skull and up into the back of the head.
The pectoralis major contributes to pain in the chest, shoulder, breast and upper back. Pain can also travel down the inner arm, elbow and extend to the hand and last two fingers.