Columbia Pain & Spine Institute

Axillary Nerve Block

An axillary nerve block is a targeted, image-guided injection that interrupts pain signals carried by the axillary nerve to relieve shoulder and outer upper-arm pain, performed at Columbia Pain & Spine Institute in Gresham and Portland, Oregon.

OVERVIEW

What an axillary nerve block is and how it works

The axillary nerve is a branch of the brachial plexus that wraps around the upper arm bone (humerus) through a region called the quadrilateral space. It supplies the deltoid and teres minor muscles and provides sensation to the skin over the outer shoulder. When this nerve is irritated or compressed, it can cause aching, burning, or sharp pain across the posterolateral shoulder and outer upper arm, sometimes with tingling.

During an axillary nerve block, one of our physicians uses ultrasound or fluoroscopic guidance to place a thin needle near the axillary nerve, typically within the quadrilateral space below the shoulder where the nerve travels around the humerus. A small amount of local anesthetic — sometimes combined with a corticosteroid — is delivered around the nerve to interrupt its pain signaling.

The block can serve two purposes. As a diagnostic tool, it helps confirm whether the axillary nerve is the source of your shoulder pain: if your pain eases after the injection, that points toward the axillary nerve. As a therapeutic treatment, the anesthetic and any steroid can calm irritation and provide a window of relief that supports physical therapy and rehabilitation.

CONDITIONS

What an axillary nerve block can help evaluate and treat

This procedure is used to evaluate and manage pain that maps to the axillary nerve’s distribution across the posterolateral shoulder and outer upper arm.

Commonly treats

Quadrilateral space syndrome Axillary nerve entrapment Posterolateral shoulder pain Deltoid-region pain Outer upper-arm neuropathic pain Post-surgical shoulder pain Persistent pain after shoulder injury
Note: An axillary nerve block is one option within a broader shoulder-pain evaluation. Your physician will recommend it only after reviewing your history, exam, and imaging to determine whether the axillary nerve is a likely source of your pain.

YOUR VISIT

What to expect during your axillary nerve block

Before

Your visit begins with a focused review of your shoulder pain, prior treatments, and any imaging. Tell us about blood thinners, allergies, or other medications, since these may affect timing. The procedure is performed on an outpatient basis, and most patients plan to have someone drive them home.

During

You are positioned to expose the affected shoulder, and the skin is cleaned and numbed with local anesthetic. Using ultrasound or fluoroscopic guidance for accuracy, your physician advances a thin needle toward the axillary nerve and injects the medication. The injection itself typically takes only a few minutes, and the full appointment is usually completed in about 15 to 30 minutes.

After

You will be monitored briefly before going home. Because a local anesthetic is used, you may notice prompt pain relief along with temporary numbness or weakness in the shoulder and deltoid — this is expected and wears off as the anesthetic fades. If a steroid is included, its anti-inflammatory effect may build over several days.

Recovery

Most people resume normal activities the next day. We often recommend keeping a simple pain diary in the hours after the block, since how your pain responds gives valuable diagnostic information and helps guide the next step in your care plan.

Image guidance matters: Performing the block under ultrasound or fluoroscopy lets us place medication precisely around the axillary nerve while avoiding nearby blood vessels and structures, supporting both accuracy and safety.

QUESTIONS

Frequently asked questions

Is an axillary nerve block diagnostic or therapeutic?

It can be both. Used diagnostically, it helps confirm whether the axillary nerve is the source of your shoulder pain based on how much relief you feel. When a corticosteroid is added, it may also provide longer-lasting therapeutic relief by easing irritation around the nerve.

How long does the relief last?

The local anesthetic provides short-term relief that may last hours, while any steroid component can extend relief for a longer period. Duration varies from person to person, and your physician will discuss what is realistic for your situation. We do not promise a specific outcome.

Will my shoulder feel weak afterward?

Because the axillary nerve also supplies the deltoid muscle, you may notice temporary weakness or numbness in the shoulder after the block. This is a normal effect of the local anesthetic and resolves as it wears off, often within a few hours.

NEXT STEPS

Considering an axillary nerve block in Gresham or Portland?

The axillary nerve block is part of our broader range of nerve block procedures and interventional pain services offered to patients across the greater Portland metro area. If shoulder or upper-arm pain is limiting your daily life, our team can help determine whether this approach is right for you.

Contact our Gresham & Portland office