If you've ever woken up with a numb or tingling sensation in your arm or arm, you may immediately wonder how and why this happened. What does "fall asleep" mean for a part of the body? »Compression of the radial, ulnar, and median nerves while lying down can cause numbness, tingling, and weakness in the upper extremities.
Learn how sleeping positions can lead to conditions like Saturday night paralysis, honeymoon paralysis, and even carpal tunnel syndrome. Fortunately, there are several treatments that can provide relief.
A part of the body is often said to be "asleep" when it feels numb (with a noticeable lack of sensation) or tingling or tingling (sometimes called paresthesia). This sensation can cause pain or other discomfort, especially after recovery.
What causes these phenomena? Many people mistakenly believe that these symptoms are due to a temporary loss of blood flow to a limb, such as a foot or an arm. In fact, the cause is most likely due to compression of the nerve supplying the body part.
Often the blood supply (including arteries and veins) passes through the nerve, which is responsible for transmitting sensory information and activating muscle activity. In some cases, an interruption in the blood supply to the nerves can lead to deterioration, but usually the symptoms are due to pressure on the nerve itself.
The sensation of falling asleep in the arm is usually associated with nerve compression rather than restricted blood supply.
Nerves can be at increased risk of damage under certain conditions. This disorder can be generalized and cause dysfunction of several nerves. Damage to the nerves is also called neuropathy. Neuropathy can be isolated from multiple nerves or even from a single nerve.
The most common generalized nerve damage is peripheral neuropathy . The longest nerves in the body, which run to the feet and legs, are often affected.
Peripheral neuropathy can be caused by diabetes , hypothyroidism , vitamin B12 deficiency, chronic kidney disease, or exposure to heavy metals. Over time, the nerves can gradually become damaged, and this damage can be irreversible.
There are also genetic disorders that can predispose affected nerves to injury. One of these disorders is known as hereditary neuropathy with pressure paralysis (HNPP). This condition results in episodes of weakness and loss of sensation, often associated with compression of individual nerves.
It is an autosomal dominant disorder, so family history is very common. Victims report frequent problems of nerve damage from daily activities, including waking up with symptoms outside of sleep.
The brain's connection to the smallest nerves in the body follows established pathways, like a system of wires leading from a power plant to an electrical outlet. Unfortunately, there is the possibility of problems that could interrupt or destroy these connections.
In addition to the brain, and even the cervical spinal cord in the neck or the brachial plexus of nerves in the armpit, there are common places where the lines can descend. Specifically, the three main nerves in the hand or arm are:
Radial nerve: Saturday night or honeymoon paralysis
Radial nerve damage may or may not cause numbness or tingling, depending on where the compression or rupture occurs. There may be variable weakness. The cause of the injury can determine what type of blow to expect.
One of the most common injuries is called Saturday night paralysis. This occurs when the radial nerve is compressed in the area of the spiral groove of the humerus (bone in the shoulder above the elbow) .
It may be due to compression of the nerve against the bone when the arm is under prolonged pressure. This can happen if your hands are placed on a chair, for example during a drunken sleep, which is why its name is associated with the night of the week when you are most likely to drink excessively.
As a result, weakness in the extension of the fingers and wrists can occur, but in rare cases, the triceps is affected. There may be loss of sensation on the back of the thumb and the first fingers.
It is also possible to damage the radial nerve above. With honeymoon paralysis, the weight of the sleeping partner's head can squeeze the nerve closer to the shoulder.
Also, the use of crutches can damage the nerve in the armpit. In posterior interosseous syndrome, there is similar weakness in the extension of the fingers and wrists, but there is no loss of sensation.
Ulnar nerve: tennis or golfer's elbow
Inflammation or damage to the ulnar nerve , most commonly ulnar, leads to common overuse conditions, such as tennis or golfer's elbow (lateral and medial epicondylitis, respectively) .
Pressure on the ulnar nerve while sleeping can also cause the arm to fall asleep. In particular, prolonged or frequent exposure to a bent elbow on a hard surface (such as a table or chair) can compress a nerve. Constant flexing of the elbow during sleep can also contribute to the development of ulnar neuropathy.
When the ulnar nerve is pinched at or near the elbow joint, weakness of the internal muscles of the arm can lead to decreased grip strength.
It can also cause numbness and tingling in the fourth and fifth fingers (ring and little fingers) and the corresponding side of the hand (called the hypothenar eminence). Weakness of the long flexor muscles of these fingers may also develop.
Compression of the ulnar nerve at the wrist is also possible. In this case, the weakness is isolated to the inner muscles of the arm and the other muscles are not affected. Similar pain or numbness may occur in the elbow of the arm.
Median nerve: carpal tunnel syndrome
Carpal tunnel syndrome is the most common neuropathy that affects only one nerve. It includes damage to the median nerve , characterized by compression as it passes under the flexor retinaculum or transverse ligament of the wrist, the tough fibrous sheath of the wrist.
In this tunnel are the tendons that flex the fingers, the blood vessels and the median nerve. Inflammation or swelling in this passage can cause symptoms that affect the arm at night.
Nighttime pain, burning, tingling, or numbness may spread to the palmar surface of the thumb, index, and middle fingers. This can be noticed upon waking from sleep. Pain can also originate in the forearm. Symptoms are often made worse by overuse of the hand or wrist.
While it can affect both hands, it is usually strongest in the dominant hand. In advanced cases, weakness or atrophy of the abductor pollicis muscle may develop, which pulls the thumb toward the hand.
In addition to the predisposing factors for peripheral neuropathy described above, the median nerve is more likely to be damaged during pregnancy, obesity, rheumatoid arthritis, gout, and other conditions .
Approximately 3.5% of the population suffers from carpal tunnel syndrome.
Is it safe to fall asleep on your hand?
Regardless of the nerve involved, you may be wondering: Is it safe for your arm to fall asleep? Fortunately, if your hand falls asleep at night, the symptoms are likely to go away before you are fully awake during the day.
In fact, periodic compression of the peripheral nerves often occurs during sleep. They can cause temporary sensory symptoms or even arm or arm weakness. Many episodes are likely to go unnoticed as sleep resumes.
Recovery from the sleeping arm is quick and a further diagnosis of treatment is seldom required.
If symptoms persist into the early hours of the morning, consider further evaluation and treatment. You may need to see your PCP for a complete history and detailed physical exam.
Your healthcare provider can refer you to a neurologist if needed, and images of the anatomy of the neck, brachial plexus, or areas of possible compression, including computed tomography (CT) or magnetic resonance imaging (MRI) , may be tools.
A neuromuscular specialist can arrange electrical studies of the peripheral nerves, including nerve conduction studies (NCS) and electromyogram (EMG) .
If left untreated, neuropathy can lead to long-term damage with persistent numbness, tingling, and loss of muscle mass or function.
It is important that you have comfortable support for your upper limb during sleep. The wrist and elbow should not be flexed or extended for long periods of time while sleeping.
If it causes you discomfort while you are awake, you should probably avoid this position for long periods of time while sleeping. Most of the time, a person wakes up and recovers, but too much alcohol or sleeping pills can cause unnecessary disruption.
In addition to the importance of neutral hand, wrist, and arm position during sleep, further intervention may be required. These options include:
Most pressure injuries usually resolve in six to eight weeks. Possible humerus fractures should be ruled out, especially those that occurred unknowingly during imbriation, as the prognosis may be worse.
Resting and avoiding triggers (such as prolonged elbow flexion) can be very beneficial. In extreme cases, decompression surgery may be necessary at the impact site .
Wrist braces or splints, non-steroidal anti-inflammatory drugs (NSAIDs such as ibuprofen, naproxen, etc.), and topical injection of corticosteroids may be helpful .
When symptoms are more severe, such as loss of sensation or muscle atrophy, surgical release of the carpal tunnel can provide immediate relief. This may require consultation with a neurosurgeon or orthopedic surgeon.
Get the word of drug information
Fortunately, waking up at night with your hand asleep is generally harmless. Pressure on the radial, ulnar, or median nerves can come from lying down. Symptoms can disappear quickly upon waking and have no long-term effects.
If symptoms occur frequently or interfere with sleep, it may be time to speak with your doctor. Simple interventions, such as wrist restraints, can provide relief. In some cases, surgery may be the treatment of choice to ensure optimal resolution and function of these vital nerves.