Sub acromial impingement (SAI) is known by a number of names although it is commonly referred to as swimmer's shoulder. SAI is where the tendons of the rotator cuff become irritated where they pass underneath the acromion (tip of your shoulder) before attaching onto the humerus. This irritation can result in a loss of movement, weakness or pain at the shoulder.
SAI is a strongly debated topic in the medical and physiotherapy profession as it was once accepted as a diagnosis but more recently that notion has been challenged. Many people define the cause of SAI as a narrowing of the joint space between the head of the humerus and the acromion. But what causes that narrowing?
This is the question argued by many professionals today. Currently causes are listed as subacromial or osteoarthritic spurs, variations in shape of the acromion, thickening of ligaments within the joint space, inflammation and thickening of the bursa and a loss of function of the rotator cuff. Does that mean if you have one of these you have SAI?
More recent research conducted by physiotherapists, orthopaedic surgeons and sports physicians have demonstrated many people in the community have an acromion that puts them at greater risk of SAI but yet they have no symptoms. Similarly patients who have had SAI in the past have recovered without removal of spurs or anti-inflammatory injections to settle down the bursa.
Common symptoms of SAI are lateral shoulder pain with movements that 'close down' the space between the head of the humerus (ball joint) and the acromion (tip of the shoulder blade). These include reaching for objects, putting the arm in a coat or doing up a bra.
Research suggests the importance of proper function of the rotator cuff in eliminating the symptoms caused by SAI. If the rotator cuff acts to pull the humeral head down during elevation of the arm, the space between the humerus and the acromion is maintained, regardless of inflammation or spurring that otherwise occurs within the area.
This puts physiotherapists as the first line of treatment for SAI to give patients every chance of improving their rotator cuff function and reducing the symptoms associated with SAI.
All Physica staff are experienced in determining the cause of SAI and can develop an appropriate rehabilitation plan to facilitate a return to normal function.