Shoulder/Rotator Cuff Injury

What is the Rotator Cuff?
The rotator cuff is located across the top of the shoulder, which is a ball-and-socket type of joint. The anatomy of the rotator cuff is actually comprised of five different shoulder muscles. All muscles consist of the belly (the "meat" in the middle) and the tendons on each end. The tendons attatch to the outer layer of the bone called the periosteum. One end of the tendon is called the origin of the muscle and the other end is called the insertion of the muscle. The rotator cuff is the tendinous insertion of the supraspinatus, infraspinatus, teres minor, teres major, and subscapularis shoulder muscles. The origins of these five muscles are located all across different regions of the scapula (shoulder blade). The infraspinatus muscle is the most common culprit in shoulder pain and attatches to the top of the shoulder blade located at the top of the back.

LOCATION - All five of these insertions are grouped very close together and form a rounded cuff that sits right across the top of the humerus, or arm bone. To locate the rotator cuff, simply place your arm on top of the opposite shoulder and lift your arm away from the body. The little groove that you feel, where the movement of the arm is taking place, is the general location of the rotator cuff. Moving the arm backwards will expose the more precise area of the cuff.

Anatomy of the Shoulder

SYMPTOMS - Upper arm pain, shoulder pain, upper back pain, especially when lifting the arm up or rotating the arm backwards.

MECHANISM OF INJURY - The rotator cuff muscles and tendons can become strained (overstreched) or torn. This is often diagnosed as tendonitis. The rotator cuff cannot actually become sprained, because a sprain involves overstretched or torn ligaments. The shoulder is one of the only joints in the body that are held together by muscles and tendons, instead of ligaments. Ligaments are like rubber bands that attatch bone directly to bone, with no muscle or tendon involvement. Repetetive motions, such as throwing a ball and lifting too much weight over the head, such as in military presses, are common movements that overload the rotator cuff. Falling on the shoulder or outstretched arm can also injure the rotator cuff.

OTHER UNDERLYING CAUSES - Muscle imbalances, poor posture, muscle stiffness, cervical and thoracic spinal fixations, scapular fixations, and general bone softening and muscle and adrenal gland weakness due to malnutrition, tension, and stress.

PREVENTION - Always warm up muscles before exercise. Gently stretch muscles after warming them up. Use caution lifting objects or weights above your head. The rotator cuff muscles are weak muscles that stabilize the joint when working overhead and are not designed for heavy loads. The deltoid muscles are stronger and can be strengthened without overloading the rotator cuff. Get checked by a licensed chiropractor for the underlying causes listed above.