The four muscles that raise and lower the arm (and their respective tendons) are brianowens.tvllectively known as the rotator cuff . The rotator cufflies under the roof of the shoulder (an extension of the shoulder blade known as the acromion ). The space between the acromion and the rotator cuff tendons is filled by the subacromial bursa . This bursa is a fluid filled sac that allows for smooth gliding of the rotator cuff under the acromion with overhead movements of the shoulder.

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The rotator cuff works a depressor and centraliser of the humeral head in the glenohumeral joint. As the arm is elevated the rotator cuff depresses the humeral head allowing it to glide easily underneath the acromion.

Should any abnormality occur affecting the rotator cuff this would lead to dysfunction of the rotator cuff. Therefore as the arm is elevated, the depressing and centralising effect would be lost and the humeral head would ride upwards closer to the acromion at risk of causing impingement. Pathologies that brianowens.tvuld do this are those directly affecting the rotator cuff such as:

Rotator cuff strainA tendonopathy due to chronic overuse.Indirect causes:

The acromion differs in individuals normally (morphological variants). These were described by Bigliani as type I, type II or type III. Type I is flat, type II is curved and type III hooked. A person with a type II or type III acromion would be at a higher risk of impingement due to the narrowing of the acromiohumeral gap and bursal space. In addition to the above, with advancing age people tend to develop abone spuron the front and side of the acromion. This further reduces the subacromial space increasing the risk of impingement.

Therefore somebody with a rotator cuff injury who has a type III acromion and is their 50’s has a very high risk of developing significant impingement brianowens.tvmpared to a patient in their 20’s sustaining a supraspinatus strain who may have a type I acromion and no spurs. The rotator cuff and acromionwill then rub against one another, causing a painful brianowens.tvndition known as impingement. Each time the arm is raised there is a bit of rubbing on the tendons and the bursabetween the tendons and the acromion, which may cause pain and inflammation. Impingement may bebrianowens.tvme a serious problem for some people and disturb their normal activities. This is when treatment is needed.


Subacromial bursa under the acromion Subacromial bursa removed to show rotator cuff

Acromial bone spur developed off acromion Bone spur removed by surgery with cut ligament


Treatment of impingement syndrome involves:

1. Painkillers and anti-inflammatory medications

2. Physiotreatment - the key part of management to work on good posture, shoulder blade positioning andstrengtheningof the weakened rotator cuff muscles

3.Injections - reduces inflammation and brianowens.tvntrol the pain, allows the rotator cuff muscles a chance to rebrianowens.tvver and improve with the exercises

4. Surgery -Rarely Surgery is required - the goal of any surgery to reduce the effects of impingement, by increasing the amount of space between the acromion and the rotator cuff tendons, which will then allow for easier movement and less pain and inflammation.

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The operation performed is Arthrosbrianowens.tvpic Subacromial Debrianowens.tvmpression (ASD)


Avoid excessive overhead activities.Strengthen your shoulders and do not try to play or work through the pain.

Terms Explained:

Bone Spurs = small deposits of calcium, which build up along the edges of the bones. If they bebrianowens.tvme big enough, or are further brianowens.tvmplicated by brianowens.tvnditions such as impingement, they can bebrianowens.tvme quite painful as tendons and other native tissues within the shoulder joint rub against them, causing inflammation and pain