Subacromial Decompression

Overview

 

Subacromial space is the area below the acromion (roof bone) of the shoulder and the underlying supraspinatus (rotator cuff) muscle. This area contains the subacromial bursa (a fluid filled pouch). This area can be very narrow and obliterated in patients with a flat (Type 2) or down sloping (Type 3) Acromion bone. The thickening of the bursa due to repetitive irritation can also be the cause of pain. 

Diagnosis

Physical examination reveals pain particularly in the terminal range of movements. 

X-ray. X-ray is performed and is useful to assess the type of the acromion (outer projecting edge of the shoulder blade) bone and for signs of arthritis. 

Ultrasound Scan. Ultrasound scan of shoulder has got a role in assessing the state of the rotator cuff muscle.

MRI Scan. MRI Scan is the gold standard investigation to identify the type and extent of the Rotator cuff tear. It also helps in understanding the condition of the muscle.

Treatment

 

Subacromial bursitis needs an arthroscopic (keyhole) surgery to create space when conservative treatments such as exercises and steroid injection have failed to improve the condition. 

Arthroscopic Subacromial Decompression Surgery

 

Subacromial decompression surgery is a day care surgery. Through arthroscopy (Keyholes), the shoulder joint is assessed and the joint structures are evaluated. The undersurface of the acromion bone and the joint between acromion and the clavicle (collar bone) is assessed. The beaking part of the acromion bone is shaved off using the bone burr. A smooth undersurface of the acromion bone with enough room for the shoulder joint to move freely is created. The thickened subacromial bursal tissue is removed. The underlying rotator cuff muscle is assessed for its integrity. 

Subacromial Decompression Rehabilitation

 

Post-surgery, you can expect to be in a broad arm sling supporting your arm. Gentle passive mobilisation is started early as soon as pain is better. Active ROM exercises are started usually by 2nd week post-surgery. Strengthening exercises typically start around 4 weeks post surgery. To achieve full functionality including lifting objects, you can expect it to take around 2 to 3 months.