What is a suprascapular nerve block?
The suprascapular nerve is responsible for providing sensation (including pain feeling) from the shoulder joint, tendons and bursa. Therefore, ultrasound guided suprascapular nerve injection can be used to block shoulder pain sensation that is the result of rotator cuff tear/cuff arthropathy or shoulder arthritis, especially when surgery is not preferred or not a suitable treatment option.
Relevant anatomy
The shoulder joint (the glenohumeral joint) is a ball and socket type joint. The ball is formed by the humeral head (the upper end of the arm bone), and the socket is formed by the glenoid, the part of the shoulder blade that articulates with the humerus. Both the ball and socket are covered by “cartilage”. This is the protective layer that lines the joints in our body to ensure smooth and frictionless joint movement.
The rotator cuff muscles are located at the front, back and on top of the shoulder blade and consist of 4 muscles (the supraspinatus, infraspinatus, subscapularis and teres minor tendons). Their tendons form a complete cuff of tissue that attach to the humerus (the ball component of the shoulder joint).
The rotator cuff tendons run immediately underneath the subacromial bursa, an important anatomical structure. A bursa is a thin fluid-containing sac usually seen adjacent to a bone to provide cushioning effect and protection.
How is suprascapular nerve block done?
In this procedure, a mixture of numbing medications (local anaesthetic) and steroids is injected around the suprascapular nerve as it passes through a special area (called the suprascapular groove) using ultrasound guidance. If the procedure is done under ultrasound guidance, the injection is usually done from the back of the shoulder. Your doctor will tell you about the appropriate position, but it is usually done while sitting on the couch with your back towards the doctor. We always recommend performing shoulder injections under ultrasound guidance to ensure accurate placement of the needle into the shoulder joint at the site of inflammation. Ultrasound guidance results in more accurate, less painful and faster procedures, with better outcomes than these injections without guidance. This will help to stun the nerve for a period of time and block the nerve fibres that transmit pain information to the brain.
What are the indications for suprascapular nerve block?
Suprascapular nerve block procedure can be useful in the management of the following conditions:
This refers to wear and tear changes that result in the loss of the articular cartilage covering the joint surface. A suprascapular nerve block can be considered when the shoulder pain is severe and the response from other treatment options (like intra-articular glenohumeral joint steroid injection) is insufficient. It is particularly considered when the symptoms are severe, but a shoulder replacement surgery is unsuitable.
When there is significant shoulder pain due to a rotator cuff tear, especially in the presence of shoulder arthritis, and when surgical treatment is not an immediate option, a suprascapular nerve block can be considered to help with pain relief.
Long-standing tears of the rotator cuff tendons can result in shoulder arthritis and significant shoulder pain. A suprascapular nerve block can be a suitable treatment option here and provide excellent pain relief, especially when surgery is not a suitable treatment option.
How long does a suprascapular nerve block last?
It is difficult to estimate exactly how long the block will last. In most people, they notice some pain relief for a few months.
What are the possible complications of a suprascapular nerve block?
In general, serious complications are very rare in suprascapular nerve block. These include a very small risk of infection, similar to other steroid injections. There is also a small risk of injury to the nerve leading to shoulder weakness (which can last from days to weeks). This is rare as the procedure is done under ultrasound guidance to ensure an accurate needle position. Please see our FAQs about steroid injection side effects.
Shoulder conditions and treatments