Acromioclavicular Joint Injection

Acromioclavicular (AC) Joint Injection

If you're dealing with shoulder pain near the top of your shoulder, especially with overhead motion or when lying on your side, you might be suffering from AC joint inflammation or arthritis. An Acromioclavicular (AC) joint injection is a minimally invasive, non-surgical treatment option that may provide quick and lasting relief. This guide explains what an AC joint injection is, whether it’s right for you, its benefits and risks, how to prepare, what to expect, and answers to frequently asked questions.

What Is an Acromioclavicular (AC) Joint Injection?

An Acromioclavicular (AC) joint injection involves placing medication, typically a corticosteroid and/or local anesthetic, directly into the AC joint, which is located at the top of the shoulder where the clavicle (collarbone) meets the acromion (part of the shoulder blade).

This procedure is commonly used to treat:

AC joint osteoarthritis
Shoulder separation (AC joint sprain or instability)
Post-traumatic arthritis
Overuse or sports-related AC joint inflammation
Chronic shoulder pain localized to the AC joint

The goal of the injection is to reduce inflammation, relieve pain, and improve shoulder function.

Is an Acromioclavicular (AC) Joint Injection Right for Me?

You may be a good candidate for an AC joint injection if:

You have localized pain at the top of your shoulder, especially when pressing on the joint.
Imaging (like X-ray or MRI) shows signs of arthritis or inflammation in the AC joint.
Activities such as reaching overhead, weightlifting, or cross-body movements cause pain.
You’ve tried NSAIDs, physical therapy, rest, or activity modification without sufficient relief.
You're hoping to delay or avoid shoulder surgery.

Benefits of Acromioclavicular (AC) Joint Injections

Key benefits include:

Targeted relief of pain and inflammation in the AC joint
Improved shoulder mobility and function
Quick, in-office procedure that takes just minutes
Minimally invasive, with no incisions and no downtime.
Can serve as a diagnostic tool, helping determine if the AC joint is the true pain source
May delay or prevent surgery in some patients

Risks of Acromioclavicular (AC) Joint Injections

AC joint injections are generally low-risk, but possible side effects include:

Temporary soreness at the injection site
Bruising or mild swelling
Infection (rare with proper sterile technique)
Skin changes such as thinning or lightening (from steroid use)
Joint stiffness or flare-up for 24–48 hours
Allergic reaction to the medication (very rare)
Tendon weakening or cartilage damage if injections are repeated too often

How to Prepare for an Acromioclavicular (AC) Joint Injection

Preparation is simple and straightforward:

Notify your provider if you take blood thinners, have bleeding disorders, or allergies to any medications.
Let your doctor know about any active infections, especially near the shoulder.
Fasting is not required. You may eat and take your regular medications unless advised otherwise.
Wear a sleeveless or loose-fitting shirt for easy access to the shoulder.
You can drive yourself to and from the appointment, as no sedation is used.

How Is an Acromioclavicular (AC) Joint Injection Performed?

The procedure is typically done in a clinic and only takes a few minutes:

Positioning: You’ll be seated or lying slightly reclined with your shoulder exposed.
Cleaning: The skin over the AC joint is cleaned with an antiseptic solution.
Local anesthetic: Numbing medication may be used to reduce discomfort.
Injection: Using a fine needle, your provider will inject medication directly into the AC joint. Ultrasound or fluoroscopic guidance may be used for accuracy.
Bandage: A small bandage is placed over the site.

You’ll be observed briefly and then allowed to go home.

Post-Procedure Care and Restrictions

After an AC joint injection:

You may have mild soreness or stiffness for 1–2 days.
Apply ice packs to the shoulder as needed to reduce discomfort.
Avoid heavy lifting or overhead activity for 24–48 hours.
Resume light use of the shoulder as tolerated.
Monitor for signs of infection such as redness, warmth, or increased pain.
Your provider may recommend physical therapy to restore range of motion and strength.

How Long Will It Last? Will I Need More?

Pain relief may begin within a few hours to a few days.
Effects can last from several weeks to months, depending on the condition and severity.
Some patients experience long-term relief, while others may need repeat injections.
Most providers limit steroid injections to 3–4 times per year per joint to prevent potential side effects.

Frequently Asked Questions (FAQs) About Acromioclavicular (AC) Joint Injections

Q: Does the injection hurt?
A: Most patients tolerate the procedure well. You may feel a brief pinch or pressure. A local anesthetic is usually given to reduce pain.

Q: Can I move my shoulder after the injection?
A: Yes, but avoid strenuous or overhead activities for 1–2 days to allow the medication to take effect.

Q: How many injections can I get in the AC joint?
A: Generally, no more than three to four injections per year in the same joint are recommended to avoid joint damage.

Q: Will this cure my arthritis?
A: While it won’t cure arthritis, it can significantly reduce pain and inflammation, making it easier to function and engage in rehab.

Q: What if it doesn’t help?
A: If your symptoms persist, your provider may explore additional treatments such as imaging, physical therapy, or surgical options like AC joint resection.

Summary

An Acromioclavicular (AC) joint injection is a safe, effective treatment for shoulder pain caused by AC joint arthritis, sprains, or inflammation. With minimal downtime and long-lasting relief, it’s an excellent option for patients looking to reduce shoulder pain and avoid surgery. If you think you may benefit from an AC joint injection, speak with your provider today.

To learn more or schedule your consultation, [request an appointment here] or call us at 832-286-4546.