Shoulder pain is common, often stemming from issues within the joint or surrounding muscles and tendons. While most shoulder discomfort arises from musculoskeletal problems, some wonder if a blocked artery could be a factor. Less frequently, certain arterial conditions can manifest as pain in the shoulder region. Understanding the connection between arterial blockages and shoulder pain provides insights for unexplained discomfort. This article explores how such a link can occur and distinguishes it from common causes of shoulder pain.
How Blocked Arteries Can Cause Shoulder Pain
Blocked arteries can cause shoulder pain primarily through referred pain. This occurs when pain from an internal organ, like the heart or blood vessels, is perceived in a different body part, such as the shoulder or arm. The brain interprets signals from internal organs and certain external body areas as coming from the same spinal nerve pathways, leading to this mislocalization.
One common example is angina pectoris, resulting from reduced blood flow to the heart muscle due to narrowed coronary arteries. When the heart muscle does not receive enough oxygen, it can cause pressure, squeezing, or tightness in the chest, often radiating to the left shoulder, arm, or jaw. This referred pain is due to shared nerve pathways between the heart and these upper body regions. The pain typically occurs during physical exertion or emotional stress and subsides with rest.
Another less common cause is a blockage in arteries supplying the arm, such as subclavian artery stenosis. This involves the narrowing of the subclavian artery, which carries blood to the arm and sometimes contributes to blood flow to the brain. When significantly narrowed, the arm muscles may not receive adequate blood supply, especially during activity. This can lead to fatigue, cramping, or pain in the arm and sometimes the shoulder, particularly during repetitive arm movements.
In severe cases of subclavian artery stenosis, subclavian steal syndrome can occur. Blood flow is “stolen” from the vertebral artery, which normally supplies the brain, to compensate for reduced flow in the subclavian artery. While neurological symptoms are more common, arm and shoulder pain can be a prominent feature due to compromised blood supply to the limb. The buildup of metabolic byproducts, like lactic acid, in oxygen-deprived muscles can also contribute to discomfort in the shoulder and arm.
Key Differences: Arterial vs. Musculoskeletal Shoulder Pain
Distinguishing arterial from musculoskeletal shoulder pain involves several key characteristics. Arterial shoulder pain, particularly from cardiac sources, often presents as a deep, dull ache, pressure, or squeezing, rather than a sharp or localized pain. This discomfort may also be accompanied by other symptoms, such as shortness of breath, sweating, nausea, or lightheadedness. The pain often radiates down the arm, frequently the left, or up to the jaw or neck.
This pain is typically triggered by physical exertion or emotional stress and tends to improve with rest. It usually does not worsen with specific movements of the shoulder joint, nor is it tender to the touch in the shoulder area. The discomfort tends to be more diffuse, meaning it’s harder to pinpoint an exact location.
In contrast, musculoskeletal shoulder pain is generally more localized and can often be reproduced by specific movements or palpation of the affected area. It might feel sharp, aching, or throbbing and often has a clear connection to an injury, overuse, or a particular activity. For instance, pain from a rotator cuff injury might worsen when lifting the arm overhead or reaching behind the back. This pain often improves with rest from the aggravating activity but may persist with certain movements.
Musculoskeletal pain may also be accompanied by stiffness, weakness, or a reduced range of motion in the shoulder joint. Tenderness to touch around the shoulder joint, especially over specific tendons or muscles, is common. The presence of a clear mechanism of injury, like a fall or repetitive strain, also points towards a musculoskeletal origin.
Common Non-Arterial Causes of Shoulder Pain
Most instances of shoulder pain stem from issues directly affecting the shoulder joint and its surrounding structures, rather than arterial blockages. One frequent cause involves the rotator cuff, a group of muscles and tendons stabilizing the shoulder joint. Injuries like tendinitis (inflammation of the tendons) or tears in these tendons, can lead to pain, especially during arm movement or at night. These conditions often result from repetitive overhead activities or acute trauma.
Another common source of shoulder discomfort is frozen shoulder, medically known as adhesive capsulitis. This condition causes significant stiffness and pain in the shoulder joint, gradually worsening over time and severely restricting the range of motion. It often develops without a clear cause but can be associated with diabetes or immobility.
Arthritis, particularly osteoarthritis, can also affect the shoulder joint, causing pain, stiffness, and a grinding sensation as the cartilage wears down over time. Bursitis, the inflammation of the bursa (small fluid-filled sacs that cushion joints), typically causes pain and tenderness over the outside of the shoulder. This pain often worsens with movement and direct pressure. Additionally, nerve impingement, such as cervical radiculopathy originating from the neck, can cause pain that radiates down into the shoulder and arm, sometimes accompanied by numbness or weakness.
When to Seek Medical Advice
Seek medical advice for any persistent or unexplained shoulder pain to determine its underlying cause. Certain symptoms accompanying shoulder pain warrant immediate medical attention, as they may indicate a serious underlying condition, such as a heart attack. These “red flag” symptoms include sudden, severe chest pain that radiates to the shoulder, arm, or jaw, especially if accompanied by shortness of breath, sweating, nausea, or dizziness. Any new shoulder pain that feels like pressure or squeezing, triggered by exertion, and subsides with rest, should also be evaluated promptly.
You should also consult a healthcare professional if shoulder pain is unexplained, does not improve with rest, or is associated with weakness or numbness in the arm or hand. Pain that significantly limits your daily activities or sleep also merits medical evaluation. While most shoulder pain is musculoskeletal, a timely and accurate diagnosis is important to ensure appropriate treatment and address any potentially serious underlying conditions. Never attempt to self-diagnose, especially when cardiac symptoms are a possibility.