Impingement as a cause of shoulder pain
Pain in the shoulder can arise from many different structures within and around the shoulder, and the neck. A common source of shoulder pain are the many bursa that exist around the joint. This can lead to conditions like shoulder bursitis and sub-acromial impingement. These conditions are particularly prevalent in overhead athletes (throwing sports), and swimmers.
What is a bursa?Bursae are fluid-filled sacs that are generally located around our joints. They act to cushion areas that are likely to be compressed. Bursae also act to decrease friction between different tissues to allow tendons and bones to slide past each other. In a joint such as the shoulder, the bursae play a key role to allow movement to happen smoothly.
Process of shoulder impingement and shoulder bursitisBursitis is a condition where a bursa becomes inflamed. This can happen after an acute incident such as a fall. Or it can happen after small, repetitive irritations – such as with swimming and repetitive overhead use. In the shoulder, the most common site for this bursal inflammation is in the sub-acromial space. This is a narrow arch above the shoulder through which some of the rotator cuff tendons pass. When the arm is repeatedly moved above shoulder height, the tendons need to pass under a bony prominence. If the rotator cuff is tight, or there is an imbalance in the musculature – the tendons and bursa can be impinged between the bony prominences of the shoulder. In a fall or acute incident, impingement and inflammation of the bursa can be very painful and block movement. This is particularly noticeable with movements of the arm out to the side and above shoulder height. In more chronic cases of bursal irritation the movement can still be blocked. Most frequently movement is painful through an arc of movement between 80-120degrees of abduction. We call this the “painful arc”. This is the most common sign of shoulder bursitis that we see. Thorough shoulder physio assessment can help determine the causes, and other involved structures.
Physio for shoulder pain from shoulder bursitisOften the first step of rehab for shoulder bursitis is to unload the bursa from irritating positions and movements. This will likely involve rest from movements above shoulder height. Overhead pressing, and pushing movements in the gym (bench press) often need to be avoided as the inflamed bursa settles. In less extreme cases, this rest can be relative – and involve a decrease in volume over overhead activity. Stretches to improve range of motion can commence in early rehab. Rather than pushing into overhead positions, early stretches often work on stretching the posterior cuff and the chest. If range of motion and pain allows, strengthening can commence. The role of strengthening is to build up strength and stability around the shoulder blade and rotator cuff. If there is a tear or strain in the rotator cuff, then this needs to be taken into account before any strength rehab can commence.
Shoulder strengthening rehabWhile boring, the physio exercises for rotator cuff strengthening are an important part of the process. First, strengthening must focus on establishing adequate scapular stability. Once this is sound, strengthening for the rotator cuff in pain-free range of motion can commence. As irritation of the bursa allows, and as range of motion improves, the strengthening can progress into great range. Exercises we like to use in shoulder bursitis rehab programs
- Theraband rowing exercises
- Seated row
- Band pull-aparts
- One-arm row
- Theraband external rotation
- Hand behind back stretching
- Pec stretching against wall