Subacromial Bursitis/Impingement Syndrome
What is Subacromial Bursitis?
Subacromial bursitis is a common problem that occurs in the middle age leading onto painful shoulder. It limits performing activities involving shoulder joint movement and can affect the quality of life significantly.
Bursa is the medical term for a lubrication sac. Lubrication sac (Bursa) is present in various locations of the human body where gliding movements are occurring eg. Joint. Subacromial bursa is the name of the lubrication sac that is present underneath a bone called Acromion in the shoulder blade. This bursa is present in a small space between the acromion of the shoulder blade and also the head of the arm bone called humerus. The space is usually around 1-2cm and this space also contains an important rotator cuff tendon called supraspinatus. The function of the tendon is elevating the arm. The normal function of the subacromial bursa is to produce jellylike substance to reduce friction in movement occurring between the shoulder blade bone acromion and the arm bone humerus.
If the lubrication sac underneath the acromion gets inflamed then the condition is called as subacromial bursitis. Inflammation of this bursa leads on to pain in the upper arm, difficulty in lifting the arm due to pain. Initially the pain occurs during overhead activities such as reaching top shelf. But further progression of the condition can lead on to difficulty in daily basic activities such as dressing up, combing hair etc. The pain can also be present in the night and can disturb overnight sleep.
What causes it?
Inflammation of this bursa is commonly seen after the age of mid 30. This is especially common in those who have lots of overhead activities in their life such as in an occupation like painting, plastering etc. It is also common in sports person performing lots of shoulder movements such as cricket, tennis and badminton. Some of them may have curved or hooked shape to their acromion bone. This inherently can reduce the available space between the acromion and the arm bone. This leads on to a tight space under the acromion and predisposes to inflammation as it gets stressed repetitively.
What are the symptoms/effects?
Inherently, when everyone lift the arm to the level of the shoulder joint, the space between the acromion and the arm bone gets narrower, If the bursa that is normally present in this space is inflamed, then the narrowing of the space pinches on the inflamed tissue. Naturally, if the inflamed tissue is pinched it will be experienced as excruciating pain in the upper arm.
How is it diagnosed?
A thorough physical assessment and clinical tests will guide towards diagnosis. X ray of the shoulder will be important to assess the subacromial space.
What are the treatment options?
Initial treatment of this condition involves giving anti-inflammatory medicines, steroid injection into the subacromial bursal space and physiotherapy exercises. Often, this can relieve the symptoms temporarily. Occasionally the symptoms can completely improve and patients may return back to their normal life. But majority of the times, the shoulder pain comes back and becomes resistant to all these treatments. In such a situation arthroscopic surgery can be useful and can resolve the pain in more than 85% of the time.