Pain Management Procedures
Acromioclavicular Joint Injection
Acromioclavicular Joint Injection
What is it?
The acromioclavicular, or AC, joint is the small joint on top of the shoulder where the collarbone meets the acromion. Arthritis, a prior shoulder separation, repetitive loading, or inflammation can cause very focused pain at this spot. An AC joint injection places a small amount of medication directly into the joint.
When may it be recommended?
It may be considered when pain is localized to the top of the shoulder and worsens with reaching across the body, pushing, lifting, or lying on that side. Because several shoulder problems can occur together, temporary relief after a precisely placed anesthetic injection may help confirm that the AC joint is an important pain source.
What happens?
The joint is shallow but small. Ultrasound or fluoroscopy may be used to improve accuracy. After cleaning and numbing the skin, the clinician advances a fine needle into the joint and injects local anesthetic, often with corticosteroid.
What should I expect?
You may be asked to repeat a movement that usually hurts while the anesthetic is active. A clear temporary improvement provides diagnostic information. Steroid relief, if it occurs, may start after several days and can last for weeks or months. Results vary.
Important risks
Short-term soreness, bruising, flushing, skin-color change, or increased blood sugar can occur. Less common risks include joint infection, bleeding, medication reaction, or injury to nearby tissue. Repeated steroid injections should be limited because of possible effects on cartilage, bone, skin, and tendons.
Preparing for your injection procedure…
Your instructions will depend on the procedure. Before any injection, tell the APG team if you:
Take aspirin, warfarin, clopidogrel, apixaban, rivaroxaban, or another medicine or supplement that affects bleeding. Never stop a prescribed blood thinner unless the clinician who manages it and the procedure team tell you how to do so safely.
Have diabetes, glaucoma, a bleeding disorder, an active infection, fever, or recent antibiotic treatment.
Could be pregnant, have an allergy to contrast dye or local anesthetic, or have reacted to steroid injections before.
Use an implanted pacemaker, defibrillator, spinal cord stimulator, or other electrical device.
Some procedures require fasting, a medication adjustment, or a responsible adult to drive you home, especially when sedation is planned. Follow the instructions provided for your specific appointment.
After your injection procedure…
Most injections are outpatient procedures. Mild soreness, bruising, temporary numbness, or a brief increase in the usual pain can occur. Follow the activity and bandage instructions you receive. Steroid medicine may take several days to have an effect and can temporarily raise blood sugar.
Call the office promptly for increasing redness, drainage, fever, severe or rapidly worsening pain, or new numbness or weakness. Seek emergency care for trouble breathing, chest pain, sudden loss of bladder or bowel control, a severe new headache, loss of vision, stroke-like symptoms, or rapidly progressing weakness.
This information is for general education and does not replace medical advice, diagnosis, or treatment. Not every procedure is appropriate for every patient, and results vary. Your APG care team will review your symptoms, examination, imaging, medical history, medications, and prior treatment before recommending a plan. Coverage requirements also vary by insurance plan.