When an arm goes numb when lifted above the head, it often involves sensations such as tingling, pins and needles, or a temporary loss of feeling and strength. This experience, medically termed paresthesia, is common. While frequently a benign and temporary issue, it can sometimes indicate underlying conditions that affect the nerves or blood vessels.
Understanding the Causes
Several mechanisms can lead to arm numbness when elevated, primarily involving compression of nerves or blood vessels. One common cause is Thoracic Outlet Syndrome (TOS), where nerves and/or blood vessels become compressed in the narrow space between the collarbone and the first rib. This compression can occur due to anatomical variations, trauma, or repetitive stress, often aggravated by overhead actions.
Another frequent cause is cervical radiculopathy, which occurs when a nerve root in the neck is compressed or irritated as it branches from the spinal cord. This can result from conditions like a herniated disc or degenerative changes in the spine as a person ages. The pain, numbness, or weakness often radiates down the arm, and certain neck movements, including overhead arm activity, can worsen symptoms.
Compression of nerves at the elbow or wrist can also contribute to arm numbness. Cubital tunnel syndrome involves the ulnar nerve at the elbow. Symptoms typically include numbness and tingling in the ring and little fingers, often worsening when the elbow is bent for extended periods. Similarly, carpal tunnel syndrome results from compression of the median nerve in the wrist, causing tingling, numbness, and sometimes pain in the thumb, index, middle, and part of the ring finger. Symptoms can sometimes travel up the arm and may be aggravated by arm elevation.
Beyond specific nerve entrapments, temporary positional compression or reduced blood flow can also cause arm numbness. Sleeping with an arm overhead or in a bent position can temporarily compress nerves or restrict blood circulation, leading to the “falling asleep” sensation. This is transient and resolves quickly once the position is changed. Additionally, muscle imbalances or chronic tension in the neck and shoulder region can indirectly contribute to nerve compression or affect blood flow.
When to Consult a Healthcare Professional
While occasional arm numbness when lifted overhead is often not a serious concern, certain symptoms warrant prompt medical evaluation. Consult a healthcare professional if the numbness persists, worsens (e.g., increasing pain, numbness, or weakness), or does not resolve quickly after changing position.
Medical attention is necessary if arm numbness is accompanied by significant pain, muscle weakness, or a loss of coordination. If the numbness follows a recent injury or trauma, seeking professional advice is important to rule out structural damage. Furthermore, if numbness affects both arms, or if it presents alongside other concerning symptoms like confusion, difficulty speaking, balance problems, or a sudden severe headache, emergency medical care is indicated. These “red flag” symptoms signal more serious underlying conditions requiring immediate diagnosis and treatment.
Relief and Prevention Strategies
Strategies can help alleviate and prevent arm numbness when lifting the arm overhead. Maintaining proper posture, especially during prolonged activities or sleep, can reduce pressure on nerves and blood vessels. Avoiding sleeping with arms tucked under the body or head, or with elbows excessively bent, can prevent temporary compression. Using a supportive pillow that maintains spinal alignment can also be beneficial.
Regular, gentle movement and stretching of the neck, shoulders, and arms can help relieve muscle tension and improve circulation. Exercises such as shoulder rolls, neck bends, and nerve gliding stretches can maintain flexibility and reduce nerve irritation. Taking frequent breaks during activities that require sustained overhead arm positions is also important. When performing overhead tasks, ergonomic adjustments, such as using lighter tools or keeping the upper arm elevation below 60 degrees, can minimize strain and reduce injury risk.
Applying heat or cold therapy to the affected areas may help manage discomfort and muscle tension. Heat can relax tight muscles, while cold can reduce inflammation. Maintaining a healthy weight and staying hydrated promote overall nerve health and circulation. If self-care measures do not provide sufficient relief, or if symptoms persist, consulting a physical therapist or other healthcare professional can lead to more targeted exercises and interventions.