An AC arm injection, more accurately referred to as an AC joint injection, is a medical procedure that involves injecting medication into the acromioclavicular (AC) joint. This joint is located at the top of the shoulder, where the collarbone (clavicle) meets the shoulder blade (acromion). The injection is typically performed under fluoroscopic guidance, utilizing a special form of real-time X-ray imaging known as a c-arm.
Why is AC Joint Injection Performed?
AC joint injections are primarily done for therapeutic reasons. They aim to relieve pain and inflammation within the AC joint. Common reasons for this procedure include:
- Osteoarthritis: Degeneration of the cartilage within the joint.
- AC Joint Injury: Sprains, strains, or dislocations.
- Inflammation: Conditions like synovitis affecting the joint lining.
How is an AC Joint Injection Done?
The procedure involves several steps:
- Patient Positioning: The patient is usually positioned on an X-ray table.
- Imaging Guidance (C-arm): A c-arm fluoroscope is used to provide real-time images of the AC joint, ensuring precise needle placement. According to provided reference a fluoroscopic guided injection involves injecting medicine directly into the joint under a special form of imaging known as a c-arm.
- Sterilization: The skin around the injection site is cleaned and sterilized.
- Injection: A fine needle is inserted into the AC joint, guided by the c-arm images.
- Medication Delivery: A combination of medications is injected, typically:
- A corticosteroid to reduce inflammation.
- A numbing agent (like lidocaine) for immediate pain relief.
- The reference says that, it is used primarily for therapeutic reasons combining a corticosteroid and numbing agent.
What to Expect After an AC Joint Injection
- Pain Relief: Patients often experience immediate pain relief from the numbing agent.
- Reduced Inflammation: The corticosteroid starts working over the next few days to reduce inflammation.
- Limited Activity: Patients are usually advised to limit strenuous activity for a short period following the injection.
- Follow-up: A follow-up appointment may be needed to assess the effectiveness of the treatment.
Benefits of AC Joint Injections
- Pain Reduction: Provides relief from AC joint pain.
- Improved Function: May lead to increased range of motion.
- Avoidance of Surgery: Can be used as a conservative treatment option, delaying or avoiding surgery.
| Aspect | Description |
|---|---|
| Purpose | To relieve pain and inflammation in the AC joint |
| Guidance | Fluoroscopic (C-arm) imaging for precise injection |
| Medication | Combination of a corticosteroid (anti-inflammatory) and a numbing agent (pain relief) |
| Outcome | Reduced pain, improved function, and a potential alternative to more invasive treatments |
