Arm Numbness Causes

Overview

A common sensation that many people encounter at some point in their lives is numbness in one or both of the arms. numbness or tingling a ‘pins and needles’ sensation is frequently accompanied by pain and weakness in the arm and/or hand. Even though brief episodes of arm numbness may be harmless and due to transient/temporary ‘pinching’ of nerves or blood vessels, persistent or recurrent episodes can point to serious health problems that need to be addressed–heart attack, stroke, multiple sclerosis and other serious disorders of the brain and spinal cord may also cause arm numbness. 

The different causes of arm numbness, associated symptoms, and appropriate treatments available will be covered in this article.

Causes of arm numbness

• Peripheral nerve compression or neuropathy:

Peripheral nerve compression is one of the most frequent causes of arm numbness. Numerous factors, including repetitive motions, poor posture, or sustained pressure on a nerve, can cause the nerves in the arms to become compressed or pinched. The median nerve in the wrist is compressed in a condition known as carpal tunnel syndrome, which results in tingling, numbness, and weakness in the hand and arm.

• Cervical radiculopathy:¹ 

When the roots of the nerves emerging from the the cervical (neck) spine are compressed or irritated, it can cause pain and numbness along the course of the nerve affected in the arms. Cervical radiculopathy the disruption of the neck spine nerve roots often results from bulging herniated discs, bone spurs, or degenerative changes in the cervical spine compressing, impinging on or inflaming the nerve roots. Symptoms are produced in a particular pattern of regions of the arm which correspond to the particular nerve root or roots affected– the level at which the nerve roots come out of the series of vertebra (spinal bones) in the neck, relate to the areas of the arm the nerves supply.

• Thoracic outlet syndrome (TOS):

The thoracic outlet is the space between the collarbone (clavicle) and the first rib. This narrow passageway is crowded with blood vessels, nerves and muscles.

In TOS, the blood vessels and/or the nerves forming a ‘junction box’ called the brachial plexus in this passageway, become compressed by other structures.² Poor posture, trauma, or anatomical variations in the musculoskeletal structures (such as an extra rib) may all contribute to this compression. Numbness, tingling, and weakness in one or both arms, especially in the upper limb, can result from TOS.

• Injury to the brachial plexus: 

The brachial plexus is a complex network of nerves like a junction box –nerves that come from various levels of the neck spine, merge and branch to supply the shoulder, arm, and hand, relaying incoming sensation and outgoing movement signals. Trauma, commonly sports and vehicle-related injuries, and complications during childbirth are among the  causes of brachial plexus injuries. Arm numbness can range from mild to complete loss of feeling, depending on the severity of the injury.

• Peripheral neuropathy: 

Diabetes, alcoholism, certain medications, infections (e.g., poliomyelitis, Lyme disease and leprosy), or autoimmune diseases are frequently the underlying cause ofr peripheral neuropathy, which is characterized by damage to the peripheral nerves . Tingling, numbness, and weakness in the arms and legs are just a few of the symptoms that it may produce.

• Raynaud’s phenomenon: 

In the condition known as Raynaud’s phenomenon the blood vessels in the fingers and toes overly constrict in response to cold weather or emotional stress. If the constriction is severe enough, the arms may also be affected, becoming numb and discoloured.³

• Cubital Tunnel Syndrome:

Cubital tunnel syndrome, is caused by compression or irritation of the ulnar nerve, which runs along the inside of the elbow through a tunnel formed of muscle, ligament and bone. Activities that involve repetitive elbow bending or prolonged pressure on the nerve (e.g., from leaning on the elbow a lot at the desk) can result in pain, numbness and tingling sensations in the hand, particularly in the ring and little fingers, which may extend to the forearm

•  Multiple sclerosis (MS):

MS is an autoimmune disease that attacks the central nervous system, causing damage to the myelin sheath that surrounds nerve fibres. As a result, nerve signals are disrupted, resulting in a variety of neurological symptoms which can include arm numbness.

Additional symptoms associated with arm numbnessDepending on the underlying cause, arm numbness symptoms can change. In addition to the loss of sensation, people may also experience:

• Arm tingling or "pins and needles" sensation
• A lack of strength or difficulty moving the arm
• A loss of grip strength in the hand
• Discolouration of the the affected arm 
• A sharp pain running down the neck or arm
• Swelling or inflammation in the affected area
• A decrease in fine motor and coordination skills i.e., clumsiness

Management and treatment for arm numbness

It is important to get checked out by a doctor if you frequently or persistently experience arm numbness. In addition to performing a thorough physical examination, your healthcare provider may also order additional diagnostic tests such as blood tests, nerve conduction studies, electromyography, and imaging such as X-rays and ultrasound. These tests assist in determining the precise reason for the arm numbness and direct appropriate management and treatment.  

Additionally, simple lifestyle changes and self-care measures may help to alleviate symptoms in some cases, depending on the underlying cause. On the other hand, medical intervention may be necessary in more severe or chronic conditions.

Among the treatment options are:

• Rest and lifestyle changes: 

In conditions such as cervical radiculopathy, TOS and peripheral nerve compressions, a factor in the development of the arm numbness may be repetitive strain injuries (RSIs), as well as muscular and structural imbalances and injury arising from chronic poor posture. In these instances, breaks from repetitive activities, rest, postural correction, stretching exercises, and the use of ergonomic tools can all help

• Physical therapy:

Physical therapy is useful in treating peripheral nerve compression and radicular nerve compression conditions, and thoracic outlet syndrome thereby  relieving their associated symptoms of arm numbness. Exercises that strengthen, stretch and rebalance the groups of muscles involved can be taught by physical therapists to remediate  nerve pressure, restore function and improve posture 

• Medications:

To treat pain and inflammation, doctors may prescribe over-the-counter painkillers or prescription drugs such as anti-inflammatories or nerve pain relievers⁴

• Corticosteroid injections: 

In cases of severe nerve compression or irritation, corticosteroid injections may be used to reduce swelling and inflammation  thereby relieving the pressure on the nerves that had resulted in arm numbness

• Treatment of underlying conditions: 

It is critical to treat and manage conditions such as diabetes, vitamin B12 deficiencies, autoimmune conditions, infections and vascular issues in order to improve peripheral neuropathy and relieve arm numbness

Prevention of arm numbness

It is possible to reduce the risk of developing arm numbness in some cases where its cause is responsive to lifestyle modifications that are under your control.⁵

Numerous factors, such as bad posture, repetitive motions, nerve compression, and underlying medical conditions, can lead to arm numbness which can be prevented or reduced by your actions– some practical steps to stop the causes of arm numbness include:

• Ensure your workspace is ergonomically designed, whether it is at home or the office. To support good posture and keep your wrists in a neutral position, adjust your chair, desk, and computer screen. Often you can request a work station assessment to help you with this. Regularly taking brief breaks to stretch and move around will also aid in easing arm tension, maintaining a good posture for the back and neck spine thereby reducing the risk of future potential problems and lowering your risk of experiencing arm numbness⁶
• Appropriate sleeping positions are very important because unhelpful ones can produce or exacerbate arm numbness. void sleeping with your arms under your head (including under your pillow) or body because this can lead to compression of nerves and/or blood vessels. Instead, sleep with your arms propped up on a pillow or by your sides to prevent nerve compression and maintain normal blood flow⁷
• Regular physical activity can improve circulation generally and lessen the likelihood of arm numbness. Concentrating  on strengthening the muscles in your arms and shoulders balancing the strength of the muscles between the shoulder blades against that of the pectoral muscles will help keep your shoulders back improving posture and head position, thereby reducing the risk of TOS and cervical radiculopathy. Also incorporate cardiovascular exercises to improve blood flow generally
• Avoid repetitive motions for long periods. The muscles and nerves in your arms can become irritated from repetitive motions such as  typing or using a mouse for long periods of time. Similarly, actions that require repeated flexing of the elbow under stress, such as lifting and pulling should be reduced. Stretching exercises canbe used frequently to relieve tension and prevent numbness
• Maintain a healthy height. Being overweight can irritate blood vessels and nerves, causing numbness in the arms. Eat a balanced diet and exercise regularly to reach and maintain a healthy weight
• Avoid wearing tight clothing and accessories, such as bracelets and watchbands, which can restrict blood flow and result in numbness in the arms. Choose comfortable, loose-fitting attire and accessories to avoid constriction of your arms
• Warm up before physical activity. Physical activity, particularly that involving repetitive arm motions, can cause muscle and nerve compression. Before engaging in such activities, warm-up exercises can help lower the danger of developing arm numbness as a consequence
• Maintain proper hydration. Maintaining healthy blood flow and avoiding nerve compression requires proper hydration. Make sure you consume enough water throughout the day
• To relieve unnecessary pressure on the nerves and blood vessels in your arms, maintain good posture while sitting, standing, and moving around
• Manage underlying medical conditions. Diabetes, carpal tunnel syndrome, and thoracic outlet syndrome are a few examples of conditions that can cause arm numbness. Effective management and treatment of these conditions can help prevent or reduce resultant arm numbness⁸

When should I see a doctor?

Sudden, unexplained left arm numbness requires immediate medical attention because it could be a symptom of a stroke or serious heart problem, so call emergency services.

However, there are many different things, from minor problems to more serious underlying conditions, that can cause arm numbness. When to see a doctor depends on a number of factors:

• The arm numbness might not be an urgent concern if it is transient and infrequent. It's best to speak with a healthcare provider if it persists or starts happening more frequently
• It is more urgent to see a doctor if the numbness is accompanied by other alarming symptoms like weakness, stiffness, pain, or tingling, or if it affects both arms
• It is advisable to see a doctor as soon as you can if the numbness is the result of an injury, particularly if there is swelling, bruising, or if you suspect a fracture

As a general rule, it is best to stay on the side of caution and schedule a visit with a healthcare provider if you are unsure of the cause of your arm numbness, if it is recurring or persistent, or if you are worried about other symptoms.

Summary

Arm numbness is a common symptom that can be caused by a variety of factors ranging from temporary and minor to more serious underlying health issues. Recognising the potential causes and symptoms is critical in determining the best treatment. If arm numbness persists or worsens, seek medical attention immediately to identify and treat any underlying conditions. Prompt treatment can help relieve symptoms, prevent further complications, and improve overall quality of life. Seek emergency medical attention if you experience sudden, unexplained left arm numbness because it could be a symptom of a stroke or a serious heart problem.