Shoulder injuries are common, and I encountered many patients with them while working as a physical therapy aid. Frozen shoulders, impingements, labrum tears, dislocations, separations, and rotator cuff tears are few that come to mind.
Individuals embark on fitness quests to lose weight, get strong, try a new activity, without giving a thought to shoulder health, when just a few regularly done exercises and a bit of shoulder awareness can go a long way toward keeping one out of a doctor’s office, or surgical suite.
Last week I went over some shoulder anatomy. I discussed the joints, “major mover” muscles, and smaller stability muscles. Check it out if you missed it. The last few components to cover are the ligaments and labrum.
- Ligaments (connect bones to bones) play an important role in stabilizing the shoulder joint and help create a structure called the shoulder capsule. There are many ligaments in the shoulder joint but two to note are the Acromioclavicular (AC) ligament and Coracoacromial ligament. The AC ligament holds the clavicle (collar bone) to the acromion of the scapula (shoulder blade) and the Coracoacromial ligament holds the acromion from the back of the scapula to the coracoid process on the front of the scapula.
- The Labrum. The tough trade off that comes into play with joint anatomy is that between mobility and stability. Joints tend to have one or the other. The shoulder is one of the most mobile joints in the body, but it lacks stability. Check out the glenoid fossa of the scapula, the “socket” that holds the arm to the body:
It’s not deep. It doesn’t encapsulate the humerus (arm bone) either. This is where the labrum helps (a little bit). The labrum is a soft layer of connective tissue that lines the inside and rim of the glenoid fossa to give it depth and better secure the arm to the body.
Common Shoulder Injuries
As stated in the beginning, there are quite a few injuries that can occur in the shoulder. I’ll never forget learning mechanisms of injury (methods of getting hurt) in one college class called Biomechanics of Musculoskeletal Injuries. “Falling on an outstretched arm” is one of the easiest ways to acquire shoulder injuries. So, just don’t fall like this and your shoulders should be okay ;-).
- Frozen Shoulder, also called adhesive capsulitis, is a condition where the shoulder capsule becomes inflamed and stiff with restricted range of motion (ROM) and pain. This condition is also the source of many of my terrible physical therapy dad jokes (Oh, your shoulder is frozen? It doesn’t feel that cold). Sometimes frozen shoulder occurs from lack of use of the shoulder, usually due to pain or other injury (for example if the arm is immobilized in a sling for a long period of time). Other times, frozen shoulder may happen spontaneously without an obvious trigger. One way to prevent this condition is to move your shoulder through the entirety of its ROM on a daily basis and address pains that prevent this movement in a timely manner.
- Shoulder Separation. One of the more common ligament injuries (also called sprains) in the shoulder occurs in the AC ligament and is known as a shoulder separation. The AC ligament connects the clavicle and the acromion of the scapula. You can feel the location easily; it’s the big bony point at the top of your shoulder.
There are 6 grades of severity in this injury. Grade 1 is the least severe, an overstretched, partially torn AC ligament, and Grade 6 is the most severe, including a complete rupture of the AC ligament, separation of those two bones, and injury to other nearby ligaments and structures. Shoulder separation injuries occur from direct impact to the shoulder (from a fall, car accident, sports accident).
- Muscle injuries (called strains) can occur in the bigger muscles (deltoid, latissimus dorsi, pectoralis major) or the smaller muscles (rotator cuff muscles, long head of the biceps, long head of the triceps). One reason injuries of the shoulder are easy to acquire is that there are a lot of muscle tendons (tendons are on the ends of muscles and connect muscles to bones) and ligaments running through the joint and not a lot of space between the bones. When one of these gets irritated and even slightly swollen (inflamed), the pressure from that increase in volume between the bones causes pain and irritation in a lot of nearby tissues.
- Dislocations or partial dislocations, called luxations or subluxations, also occur in the shoulder joint, primarily because of that tradeoff between mobility and stability. The size of the muscles and structures holding the arm in the shoulder are fairly small and unstable (compared to those in other joints, for example those holding the leg in the hip). 95% of shoulder dislocations occur anteriorly, or to the front of the body from direct blows to the shoulder or falling on an outstretched arm.
The other directions of dislocation are posteriorly (to the back of the body), often from electric shock or seizure, and inferiorly (downward) which is the rarest kind. The process of fixing a dislocation or returning the arm to its socket is called a reduction, and [PSA] if you ever find yourself with a dislocated shoulder, please fight the urge to reduce it yourself, and let a medical professional do it.
- Labrum Tears. The labrum lines the “cup” where the arm bone is held to the shoulder blade to give a little more stability and security to the joint. It can be damaged during repetitive shoulder motions (throwing, weightlifting) or from traumatic incidents (falling on an outstretched arm, direct blow to the shoulder, sudden pulling of the arm, quickly reaching overhead to stop a fall or slide).
Prevent Shoulder Injuries
While we can’t do much to prevent injury from freak occurrences like falls and accidents, there are a few weekly or bi weekly exercises and a few avoidances as well that can help prevent shoulder injuries.
- Strengthen the rotator cuff muscles (teres minor and infraspinatus) with external rotations. This will increase the size of those muscles, the space in the shoulder joint, and the stability of the shoulder. Start really light with these movements, but don’t be afraid to increase strength. Don’t go to failure, though. This can leave the shoulder unsupported and more prone to injury.
Notice how these are performed with the arm at a 30 degree angle from the body and not right alongside it.
- Learn how to bench press properly! Keep your shoulder blades retracted and depressed, have a little arch to your back, keep your elbows at a 45 degree angle to your body, and use your feet. Check out Eric Cressey’s Shoulder Savers Article for more information on correct form.
- Back Attack! Use the Seated Cable Row with strict form to train proper scapular retraction (squeezing shoulder blades together behind the body).
- Upright row with caution. Done with a barbell, the humerus is extremely internally rotated and is elevated into the “impingement zone” each rep. A safer option is performing it with dumbbells (or not at all).
- Maintain your mobility! Try out this awesome warmup.