Numerous conditions can cause underarm or armpit pain. For example, the armpit is a common location for lymph node enlargement. Other structures in or around the armpit--such as nerves, muscles, bones and blood vessels--can cause underarm pain or discomfort. Underarm pain may be caused by traumatic injury, nervous system disorders or certain medical conditions. Some types of underarm pain require medical intervention to help resolve the underlying cause of the symptoms. See you doctor for an accurate diagnosis if you have underarm pain.
If you are experiencing serious medical symptoms, seek emergency treatment immediately.
Brachial Plexus Injury
Brachial plexus injuries can cause underarm pain. The brachial plexus is a network of nerves located in the neck and shoulder, which also course through the armpit. This network of nerves can be damaged by pressure, stretching or trauma. Traction of the brachial plexus nerves is one of the most common types of brachial plexus injuries, occurring when the head and neck are forced away from the affected shoulder, toward the opposite side. In severe cases, the nerves may tear away from their roots in the cervical spine or neck. Possible signs and symptoms associated with brachial plexus injuries include underarm pain, numbness and tingling in the arm and reduced motor control of the arm muscles.
- Brachial plexus injuries can cause underarm pain.
- In severe cases, the nerves may tear away from their roots in the cervical spine or neck.
Causes of Pain in the Upper Left Hip
Lymphadenitis -- an infection of the lymph nodes or glands -- is a common complication of certain types of bacterial infection 3. The lymph nodes are small structures that are responsible for filtering toxins out of the body. The lymph nodes contain a substantial amount of white blood cells that help ward off infection. Lymphadenitis manifests when the lymph nodes become enlarged due to inflammation 3. The inflammation is usually a reaction to invading bacteria, viruses or fungi. Swollen lymph nodes are often located near areas of underlying infection, inflammation or tumors. Lymphadenitis can occur in any lymph node, including the axillary lymph nodes, or the nodes in the armpit 3. Common signs and symptoms associated with lymphadenitis include swollen, tender and hard lymph nodes and red, tender skin over the affected nodes 3.
A shoulder dislocation can cause underarm pain 1. The shoulder is the body's most mobile joint, which makes it prone to dislocations. A shoulder subluxation is a partial dislocation of the shoulder in which the head of the upper arm bone partially slips out of the shoulder socket. A dislocation means that the head of the upper arm bone completely slips out of the shoulder socket 1. Both conditions cause significant pain and discomfort in the shoulder and underarm. The majority of shoulder dislocations involve a downward and forward slippage of the upper arm bone. Common signs and symptoms associated with shoulder dislocation include swelling, numbness, weakness and bruising in the affected shoulder and underarm.
- A shoulder dislocation can cause underarm pain 1.
- Common signs and symptoms associated with shoulder dislocation include swelling, numbness, weakness and bruising in the affected shoulder and underarm.
Causes of Pain in the Upper Left Hip
Causes of Pain on the Right Side of the Neck Down to the Shoulder
What Are the Causes of Pain, Numbness & Tingling in the Left Arm?
Causes of Left Shoulder Blade Pain
5 Things That Cause Pain Behind the Ear and Down the Neck
Pain and Swelling in the Shoulders, Arms and Hands
Shoulder Popping While Rotating During Swimming
Signs & Symptoms of Shoulder Injuries
Causes of Pain on the Right Side Under the Arm
Common Rear Shoulder Injuries
- Annals of the Royal College of Surgeons of England: Anterior Shoulder Dislocation
- American Association for Surgery of the Hand: Brachial Plexus
- MedlinePlus: Lymphadenitis
- U.S. National Library of Medicine: MedlinePlus. Lymphadenitis. Updated June 2, 2020.
- West H, Jin J. Lymph nodes and lymphadenopathy in cancer. JAMA Oncol. 2016;2(7):971. doi:10.1001/jamaoncol.2015.3509
- Gaddey HL, Riegel AM. Unexplained lymphadenopathy: Evaluation and differential diagnosis. Am Fam Physician. 2016;94(11):896-903.
- Johns Hoppkins Medicine. Lymphadenitis.
Martin Hughes is a chiropractic physician, health writer and the co-owner of a website devoted to natural footgear. He writes about health, fitness, diet and lifestyle. Hughes earned his Bachelor of Science in kinesiology at the University of Waterloo and his doctoral degree from Western States Chiropractic College in Portland, Ore.