Subacromial Bursa Injection

Subacromial bursal corticosteroid injections, also known as subacromial-subdeltoid bursal injections, are used in patients with limited or no response to initial treatment with impingement syndrome, subacromial bursitis, subacromial pain syndrome, and/or rotator cuff disorders. Non-steroidal anti-inflammatory drugs (NSAIDs) and activity modification are the initial treatments to reduce the pain and inflammation. 
Subacromial-subdeltoid bursal injections are relatively straightforward and well-tolerated procedure by the patients, although using larger than necessary needles and going into the cuff tendons are not so well tolerated. Emphasis should be made on the importance of post-procedure physiotherapy. Corticosteroid containing injectate can be injected into the appropriate space confidently under ultrasonographic guidance, and vascular, neural and tendons are avoided with certainty during the procedure.
==Anatomy==
The subacromial subdeltoid bursa is located beneath the acromion process. It is below the deltoid muscle, and superficial to the rotator cuff tendons, biceps tendon sheath, and glenohumeral joint. On ultrasound imaging, the normal bursa is a thin hypoechoic structure that measures around 1mm in thickness, and is found between the subdeltoid flat plane and a fat plane superficial to the rotator cuff. Bursitis is indicated by enlargment, thickening, and it may be filled with echogenic material. Bunching may be seen with provocative manouevers.
==Indications==
* symptomatic subacromial impingement syndrome
* rotator cuff disorder
* diagnostic injection
* as part of a barbotage procedure for calcific tendinopathy
==Contraindications==
Infection/cellulitis of the overlying skin, osteomyelitis of the adjacent bone and bacteraemia are absolute contraindications.
Allergic reaction to disinfectants and local anaesthetics, more than 3-4 corticosteroid injections per patient per year, poorly controlled diabetes, coagulopathy, and glaucoma are relative contraindications.
==Pre-procedural Evaluation==
review contraindications, review previous images, perform complete ultrasound study of the affected shoulder to confirm a diagnosis, informed consent
==Equipment==
* sterile gauze
* sterile gloves 
* skin disinfectant
* 21 to 27 gauge long needles
* local anaesthetic: 1-1.5 mL of bupivacaine 0.5%
* corticosteroids: 0.5 mL of dexamethasone 4 mg/mL
==Technique==
The skin is disinfected. Sterile gloves are worn, and a 21-27 gauge needle is used to penetrate the skin parallel or oblique concerning the surface of the probe and 2 cm away from the probe. The needle's progress is monitored in real time with ultrasonographic guidance, and the injection is performed when the tip appears to be inside the bursa. Hypoechoic fluid can be seen spreading inside the bursa while injecting. The thinner the needle, the more difficult it is to identify the needle and to perform the injection.
A dose of corticosteroid (0.5 mL of dexamethasone 4 mg/mL) with local anaesthetic (1-1.5 mL of bupivacaine 0.5%) can be used for analgesic effect.
===Ultrasound Guided===
US-guided corticosteroid injections into the subacromial-subdeltoid bursal space are carried out with the patient sitting on a chair with the patient's back turned to the doctor. Lateral approach is the most frequently used approach in which the long axis of the supraspinatus is parallel to the probe. The appropriate position of the shoulder is identified with ultrasound (the thickest part of the bursa or the area with more fluid accumulation in the bursa), the patient is asked to stay still and keep the position.
Lateral approach is the most frequently used approach in which the long axis of the supraspinatus is parallel to the probe, and the needle is inserted parallel or oblique in relation to the probe and 2 cm away from the probe to avoid the sterile needle contact with the probe.
The bursa is a large structure that can accommodate a significant amount of injectate infiltration, and so should not distend significantly with injection. If you see significant bugling then you are not in the correct plane.
===Non-ultrasound Guided===
==Complications==
Infection is an infrequently occurring complication but should be included in the consent, along with bleeding and allergy. Vasovagal reaction within 5-10 minutes post-procedure can occur and lying patients down for these procedures prevents any unnecessary injuries if one was to occur. Flushing of the skin within 2-3 days after the injection can occur but are more common with intra-articular corticosteroid injections.
==Aftercare==
Avoidance of shoulder overuse for 2-3 days is recommended to the patients.
Symptoms suggesting infection and the possibility of pain and rash at the site of the injection are explained to patients.
==Videos==
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<youtube>https://www.youtube.com/watch?v=8BqRMm5sx44</youtube>
<youtube>https://www.youtube.com/watch?v=NdyPZNhoj08</youtube>
==See Also==
Shoulder
==External Links==
==References==
#Weidner S, Kellner W, Kellner H. Interventional radiology and the musculoskeletal system. (2004) Best practice & research. Clinical rheumatology. 18 (6): 945-56. doi:10.1016/j.berh.2004.05.011 - Pubmed
#Sibbitt WL, Peisajovich A, Michael AA, Park KS, Sibbitt RR, Band PA, Bankhurst AD. Does sonographic needle guidance affect the clinical outcome of intraarticular injections?. (2009) The Journal of rheumatology. 36 (9): 1892-902. doi:10.3899/jrheum.090013 - Pubmed
#Molini L, Mariacher S, Bianchi S. US guided corticosteroid injection into the subacromial-subdeltoid bursa: Technique and approach. J Ultrasound. 2012;15 (1): 61-8. doi:10.1016/j.jus.2011.12.003 - Free text at pubmed - Pubmed citation
#Molini L, Mariacher S, Bianchi S. US guided corticosteroid injection into the subacromial-subdeltoid bursa: Technique and approach. J Ultrasound. 2012;15 (1): 61-8. doi:10.1016/j.jus.2011.12.003 - Free text at pubmed - Pubmed citation
Category:Infoboxes
Category:Partially complete articles
Category:Shoulder Procedures