A Guide to Pain in the Left Arm: Causes and Treatments
A problem with any part of the arm can result in pain. However, arm pain can originate away from the arm itself.
The arms have three sections — the upper arm, forearm, and hand. Each arm has 30 bones that form the hand, wrist, elbow, and shoulder. There are also several muscles, nerves, and blood vessels.
The nerves that run down the arm come from the brachial plexus. This is a group of nerves that branches out from the spinal cord.
If you have a neck or upper spine disorder, you may also experience pain in the arms. In addition, heart problems can cause pain to radiate to the left arm due to its closeness to the heart. Sometimes, even pain in the right arm can signal a heart attack or another problem.
There are many words to describe how left arm pain feels, including:
Sometimes, you may feel the pain constantly. Other times, it may only occur due to certain activities or positions. The pain may feel better after resting or using the arm.
Left arm pain can occur alone or with other symptoms. Describing how the pain feels and when it occurs can help doctors find the cause.
Depending on the cause of left arm pain, other symptoms can occur. These include:
- numbness or tingling
- reduced range of motion in a joint
Along with pain in the left arm and shoulder, symptoms that may indicate a heart-related problem include:
- chest pain, pressure, fullness, or squeezing
- heart palpitations
- neck, jaw, or back pain
- lightheadedness or fainting
- nausea and vomiting
- shortness of breath
- sudden anxiety
If you experience any of these potentially serious symptoms, seek medical care.
The most common causes of pain in the left arm fall into four categories:
Musculoskeletal conditions affect the bones, muscles, ligaments, tendons, and connective tissues. The following conditions can cause pain in the left arm:
- arthritis, including osteoarthritis, rheumatoid arthritis, and other forms of joint inflammation
- fractures or dislocations, or separations, where the bone in the joint becomes displaced
- rotator cuff injury
- sprains and strains
Neurological conditions affect the brain, nerves, and spinal cord and can cause left arm pain. Conditions include:
- cervical spine disorders, including herniated disc, radiculopathy, and spondylosis
- peripheral nerve compression, including carpal tunnel syndrome and cubital tunnel syndrome
- peripheral neuropathy, such as from diabetes
Vascular conditions affect the heart and blood vessels. Conditions that cause pain in the left arm include:
- peripheral vascular disease
- thoracic outlet syndrome, which compresses nerves and vessels exiting the chest to the arms
Other conditions that can cause pain in the left arm include:
Diseases or other medical conditions that affect the lung or certain abdominal organs, such as the pancreas and spleen, can also cause pain in the left arm.
Seek emergency medical care or call 911 if you experience sudden arm pain and other symptoms that could indicate a heart attack.
Other reasons to seek emergency care for arm pain include:
- coolness, discoloration, or no pulse in the arm
- difficulty or inability to move the arm, hand, or fingers
- fever and chills
- gaping wound
- numbness or loss of sensation in the arm, hand, or fingers
- obvious deformity or a bone breaking through the skin
- severe pain or swelling
Contact your doctor for advice or an appointment if left arm pain lasts more than a couple of weeks despite home treatment. You could also contact your doctor for arm pain if:
- Certain activities aggravate the pain.
- The pain changes in nature or severity.
- The pain occurs even at rest.
- The pain goes away but recurs.
- You have an area of swelling or lump near the pain.
To diagnose the cause of left arm pain, your doctor will take a medical history and perform an exam.
Questions your doctor may ask you about the pain in your left arm include:
- When did the pain start? What were you doing?
- Is the pain in one spot or all down the arm?
- How long have you had the pain?
- How would you describe the pain?
- What, if anything, makes the pain better or worse?
- Does the pain radiate from other areas?
- How often do you get the pain, and how long does it last?
- What other symptoms are you having?
- What other medical conditions do you have?
Depending on what your doctor finds on the exam, they may want to do other tests, including:
- blood tests, including a complete blood count and basic metabolic panel
- nerve conduction tests or electromyography (EMG), which are nerve studies that evaluate how well your nerves send signals and how your muscles respond to them
- imaging exams, such as X-ray, CT scan, MRI, or ultrasound
Sometimes, these test results may mean you will need further testing or an invasive procedure, such as arthroscopy.
The treatments for pain in the left arm depend on the cause. Options may include medications, corticosteroid shots, bracing or splinting, or physical therapy. Sometimes, you may need a cast or surgery.
Sometimes, left arm pain will respond to home treatment with the RICE approach:
- Rest from the activity that causes the pain.
- Ice the area with a cold pack for 20 minutes several times a day.
- Compression bandages can help keep the swelling down.
- Elevate the arm above the level of your heart to decrease swelling.
Contact your doctor if these measures do not improve your arm pain within a couple of weeks.
Like the treatments, the potential complications of left arm pain will depend on what is causing it.
Here are some questions people often ask about pain in the left arm.
When is pain in the left arm a medical emergency?
Pain in the left arm is a medical emergency if it occurs after an injury that might result in fracture or dislocation, also known as separation, where the bone in the joint becomes displaced from its usual position.
It could also be an emergency if you experience symptoms of a heart attack or infection alongside the pain.
How do you know if pain in the left arm is not heart-related?
Left arm pain is less likely to be heart-related when it occurs alone. However, sudden arm pain or pain with other symptoms of a heart attack needs immediate medical attention.
How do I know if left arm pain is serious?
You may need to take action about left arm pain when it starts suddenly or occurs with other heart attack symptoms. Seek medical care if left arm pain occurs with exercise or activity but subsides with rest.
Other serious symptoms to look out for include numbness, coolness, discoloration, or difficulty moving your arm. If you are in any doubt about left arm pain, it is best to err on the side of caution and seek medical care.
Left arm pain can have many causes. Often, it stems from a problem with nerves or the musculoskeletal system.
However, pain in the left arm can also signify heart problems, such as a heart attack. This pain usually radiates from the chest and may involve the shoulder, back, neck, or jaw.
Other symptoms you have can help your doctor determine the cause. If you have any worries about the cause of left arm pain, contact a doctor as soon as possible.