From the Guidelines
For rotator cuff tendinitis, the subacromial space is the recommended injection site, as it allows for targeted delivery of corticosteroids and anesthetics to reduce inflammation and alleviate pain, while minimizing the risk of tendon rupture or other adverse effects. When administering an injection for rotator cuff tendinitis, it is crucial to prioritize the subacromial space, located between the acromion process of the scapula and the humeral head, as the optimal infiltration site. The procedure typically involves injecting a mixture of corticosteroid (such as methylprednisolone 40mg or triamcinolone 20-40mg) combined with a local anesthetic (like lidocaine 1% or 2%, 2-5ml) 1. Some key considerations for the injection procedure include:
- The patient should be seated or lying down with the arm in a relaxed position
- The needle should be inserted laterally, 1-2 cm below the lateral edge of the acromion, directed slightly upward and medially
- Ultrasound guidance is highly recommended to improve accuracy and outcomes by ensuring proper placement within the subacromial bursa, avoiding tendon injection which could lead to rupture 1
- Patients should rest the shoulder for 24-48 hours after injection and gradually resume activities Relief typically begins within 2-3 days and may last several weeks to months, as this approach works by reducing inflammation in the bursa and surrounding tendons, decreasing pain and improving mobility in the shoulder joint. It is essential to note that while the evidence is not conclusive, the potential risks associated with injecting corticosteroids into the tendon substance, such as reducing the tensile strength of the tissue and predisposing to spontaneous rupture, emphasize the importance of precise injection technique and careful patient selection 1.
From the Research
Administration of Injections for Rotator Cuff Tendinitis
- The administration of injections for rotator cuff tendinitis can be done in the subacromial space, as indicated in studies 2, 3, 4.
- Subacromial injection has been used for various types of injections, including platelet-rich plasma (PRP) 2, 3, 4, corticosteroid 3, 4, and prolotherapy 3.
- The use of ultrasound guidance for injections in the subacromial space has also been mentioned in some studies 3, 4.
- Landmark-guided PRP injection in the subacromial space has been used in some cases, as seen in study 2.
Types of Injections
- Platelet-rich plasma (PRP) injections have been used to treat rotator cuff tendinitis, with some studies showing improvement in symptoms 2, 4, 5.
- Corticosteroid injections have also been used, providing short-term relief for pain, function, and quality of life 3, 4, 5.
- Prolotherapy injections have been used in some cases, although the evidence for its effectiveness is limited 3.
- Other types of injections, such as stem cells and ultrasound-guided barbotage for calcific tendinitis, have been mentioned in the literature, but the evidence for their use is sparse 6.