The shoulder is one complicated joint. Unlike a simple hinge joint like the knee, the shoulder can move in all directions because motion comes from many different places. When reaching overhead the arm bone (humerus) spins in the socket and the shoulder blade (scapula) glides up and away along the rib cage; the collar bone spins and tilts on each end where it connects the scapula to the chest bone. Luckily, with healthy shoulders we don’t need to orchestrate reaching up; it just happens. But keeping shoulders healthy as we age means maintaining flexibility and strength…and it all begins with a healthy rotator cuff.
WHAT EXACTLY IS THE ROTATOR CUFF?
The rotator cuff is a group of four muscles that blend together to keep the upper end of the humerus securely centered in the socket. The muscles all originate on the scapula and attach to the front of the shoulder on the humerus via the rotator cuff tendons. Individually, the muscles can rotate the arm inward or outward. By working as a team they stabilize the humerus bone in the socket, so the larger muscles like the deltoid can lift the arm. Without a functioning rotator cuff, we cannot lift the arm. Tendon tears are common, and with large tears we may not be able to use the arm even to brush our teeth. Keeping the rotator cuff healthy is key for long term function as we age; studies show that up to 20% of those over age 70 have a complete, “full thickness” rotator cuff tear.
WE WANT TO PRESERVE OUR ROTATOR CUFF TENDONS! Simply put, we want to preserve the integrity of our rotator cuff tendons. This means avoiding both traumatic cuff tendon tears and the more common degenerative tears that occur over time. Here are some of the most common causes of rotator cuff problems:
- SUDDEN TRAUMA – A fall can do it; so of course preventing the fall is key. (Think balance training, hiking poles, good shoes). Also common are retractable dog leash injuries. The dog charges after the squirrel and before you realize it the cuff tendons are stretched as the humeral bone is pulled from the socket.
- REACHING IN THE BACK SEAT, and then lifting that gym bag or briefcase. Repetitive strains like this can lead to tendonitis and degenerative tears. By reaching the arm awkwardly back and then contracting the cuff when the arm is in poor alignment, the cuff can be stretched and pinched. Instead, make sure you face what you are lifting by turning your body or better yet, get out and open the back door.
- LIFTING AND CARRYING WEIGHT THAT IS TOO HEAVY: We all have physical limits and so does tendon tissue. More is not always better when it comes to strengthening the shoulder. It’s not only barbells either… It is also tempting to carry ALL the grocery bags at once to save a trip, or move the piano yourself instead of waiting for help.
- WEAK SCAPULAR STABILIZERS: If the muscles that hold the shoulder blade on the rib cage are weak, then the rotator cuff may be at risk for a degenerative tear. Remember the socket of the shoulder joint is actually a part of the scapular bone. If the scapula is winging way from the spine then this changes the angle of the socket, causing poor shoulder alignment. Strong scapular muscles let us push and pull without straining the rotator cuff.
- TIGHT PECS, LATS AND TRAPS: Pectoralis Major, Latissimus Dorsi, Upper Trapezius. These are large, strong lifting muscles that can become short over time, pulling the shoulder forward and limiting the ability of the shoulder blade to glide freely along the ribs. Maintaining flexibility allows good shoulder alignment and reduces impingement on the rotator cuff. (THINK POSTURE)
A WORD ABOUT SHRUGGING: We have all likely been told to relax our shoulders and neck. This makes sense if we are seated at a computer or doing other activities with our hands at our sides. But when we are lifting weights overhead or reaching up to the sky in a yoga class, shrugging is a healthy part of the motion. Shrugging is when the scapula elevates and rotates upward. SHRUGGING IS NOT A DISEASE! The healthy scapula is free to glide upward helping to provide a good portion of our overhead reach. By elevating and tilting the shoulder blade upward we are preventing the rotator cuff from being pinched between the acromion process (tip of scapular bone) and the arm bone. We should never try to jam the shoulder blades all the way downward when the arm is overhead.
In conclusion, a shoulder wellness program should center around rotator cuff protection and your personal trainer is in an ideal position to design the program that is right for you. This will include cuff strengthening, scapular flexibility and scapular strengthening. Be aware of posture and alignment (see OCTOBER 2015 newsletter). Use good body mechanics to avoid over-stressing the cuff tendons. And if you develop shoulder pain, consider an evaluation by a physical therapist for guidance and treatment to avoid a chronic shoulder problem.
Thank you Greg Blais, PT at Mountain Physical Therapy for writing such an excellent article for our newsletter