Abductor digiti minimi hand muscle contributes to pain on the outside of the hand radiating up into the little finger. Pain can be sharp when moving the little finger. The outside pad of the hand will often have a dull ache.
The extensor digitorum is located in the back of the forearm. It contributes to pain in the back of the hand and middle finger which sometimes radiates up into the back of the wrist and the back of the forearm. Pain is occasionally felt in the front of the wrist, just below the palm.
The flexor digitorum profundus muscle is found in the front of the forearm. It can contribute to pain and twitching in the four fingers. It can affect one or any combination of the fingers. It can also cause trigger finger, where a finger will lock in a bent position.
The lumbrical muscles of the hand contribute to pain in the back of the hand and the fingers. Pain in the index finger and/or the little finger are most common. Stiffness in the finger joints mimics arthritis pain. Stiffness and pain when opening and closing the hand is also common.
The flexor digitorum superficialis is located in the front of the forearm. It contributes to pain in the four fingers, the palm, and occasionally the wrist. The muscle is a major contributor to trigger finger.
The flexor carpi ulnaris muscle is located on the inside (pinky side) of the forearm. It contributes to pain in the wrist, palm of the hand, and the ring and little fingers. Pain is sometimes felt in the elbow.
The extensor indicis muscle is located in the back of the forearm. It contributes to pain in the back of the wrist, hand, and index finger. The pain will often feel like you have sprained or strained the back of the hand. It can also cause charley horse like cramps in the index finger.
The flexor pollicis longus muscle is located in the forearm, same side as the thumb. It contributes to pain in the middle joint and tip of the thumb. Pinching motions between the forefinger and thumb can cause intense pain. It can also cause the middle thumb joint to pop and sometimes lock.
The extensor carpi radialis brevis muscle is located in the back of the forearm on the side of the thumb. It contributes to a burning pain in the back of the hand that sometimes extends up to the forearm. Twisting the wrist can cause excruciating pain. It also can cause a weakened unreliable grip.
The extensor carpi radialis longus contributes to pain in the elbow, forearm, back of the hand and first finger. It contributes to tennis elbow and can cause a weak unreliable grip.
The latissimus dorsi muscle can contribute to pain in the shoulder, upper back, and arm going down into the hand. The muscle can also cause pain in the side of the ribcage and lower abdomen. It is the muscle that most often causes the 'side stitch'.
The subclavius muscle is found just under the collarbone. It contributes to pain in the area around the clavicle (collarbone), shoulder, upper arm, forearm, thumb and fingers. It can also contribute to tingling and numbness in the arm and hand.
Scalene muscles are a prime contributor to thoracic outlet syndrome as well as neck, shoulder, chest, upper back and arm pain. Muscle twitching, jerking and restlessness similar to restless leg syndrome felt in the neck and shoulder is a classic sign of scalene dysfunction
The coracobrachialis muscle connects the shoulder to the upper arm. It can contribute to pain in the shoulder, back of the arm, and occasionally the middle finger. Pain is often felt when attempting to put your hand behind your back and or raising your arm over your 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.
The serratus posterior superior muscle is a muscle found in the upper back. It contributes to pain in the shoulder, shoulder blade region, arm, hand and little finger. It can also contribute to pain in the upper chest.
The teres minor connects the shoulder blade to the upper arm and is one of the rotator cuff muscles.