What is Hand Nerve Compression Syndromes?
Nerve compression syndromes in the hand occur when a nerve is squeezed. This can cause various symptoms like pain, numbness, or weakness in the hand. Specifically, the three nerves that might be involved are the median, ulnar, and radial nerves. Each of these nerves has a specific pattern of areas in the hand they reach, which helps doctors identify which nerve is affected based on your symptoms.
The median nerve both receives and sends signals for sensation and movement. It originates from the side and middle cords of the brachial plexus—a network of nerves in the shoulder area. This nerve runs down the inner side of the arm, dives through the middle of the forearm, and enters the hand through the carpal tunnel—a narrow passageway in the wrist. It controls certain muscles in the forearm and hand, and senses touch in the thumb and first few fingers.
The ulnar nerve also sends and receives signals for sensation and movement. It starts from the ventral rami of the eighth cervical and first thoracic spinal nerves, which are in the neck and upper back area. This nerve runs down the arm alongside the artery, near the inner side of your elbow, and carries on down the forearm. It enters the hand lateral to the tendon of the forearm’s inner part and controls certain muscles in the forearm and hand. It senses touch in the little finger and part of the ring finger.
The radial nerve, which also carries both sensation and movement signals, starts from the ventral rami of the fifth cervical to first thoracic spinal nerves. This nerve travels along the back side of the upper arm, and towards the front of the elbow. It controls several muscles in the arm and forearm and senses touch on the back side of your arm and forearm, as well as the back of your hand and thumb, and part of your first few fingers.
Understanding these nerves and how they work helps doctors identify and treat nerve compression syndromes in the hand. By knowing which nerve is affected, we can provide the right treatment to relieve your symptoms.
What Causes Hand Nerve Compression Syndromes?
Various factors can cause syndromes that result from nerve compression. These include external pressure, abnormal body structures, and both local and systemic conditions. External forces such as leaning on a body part, or even pressure from medical equipment like splints or casts can squeeze the nerve, creating heightened or prolonged pressure.
Additionally, structural abnormalities in your body can promote nerve entrapment. For instance, growths or lumps like lipomas (fat tissue), fibromas (fibrous tissue), ganglion cysts (fluid-filled lumps), or hematomas (collection of clotted blood outside of a blood vessel) can add further pressure.
In some cases, local conditions such as osteoarthritis, rheumatoid arthritis, and gout can also play a role in nerve compression. Obesity, chronic inflammation, diabetes, underactive thyroid (hypothyroidism), swelling (peripheral edema), and pregnancy are systemic issues that can contribute to squeezing nerves as well.
All these factors lead to inflammation, which contributes to the symptoms related to nerve compression.
Risk Factors and Frequency for Hand Nerve Compression Syndromes
Carpal tunnel syndrome is a common condition where a nerve in the hand becomes compressed. In the United States, it affects 1 to 3 people in every 1000 each year, with approximately 50 people in every 1000 currently living with the condition. It is most common in women, who are ten times more likely to be affected than men. The risk increases with age and is associated with activities or jobs that involve repetitive actions with the hand or upper arm. Conditions that cause long-term inflammation, like diabetes or hypothyroidism, are also frequently linked to the development of this syndrome.
- Carpal tunnel syndrome is the most common and well-studied nerve compression condition for the hand.
- In the United States, it affects 1 to 3 people per 1000 each year, and about 50 in every 1000 people have this condition.
- Women are ten times more likely to have it than men.
- The risk of developing this condition increases with age.
- Jobs or activities that involve a lot of repetitive hand or upper arm movements increase the risk of developing this syndrome.
- Conditions that cause continuous inflammation, like diabetes or hypothyroidism, are often involved in the development of nerve compression.
Signs and Symptoms of Hand Nerve Compression Syndromes
Nerve compression syndromes can vary widely in terms of their symptoms, depending on which nerve is affected. It’s crucial for doctors to get a detailed description of a patient’s symptoms, including how long they have been experiencing them. A patient’s medical history can also provide important context, as conditions like autoimmune diseases, diabetes, heart disease, osteoarthritis, pregnancy, obesity, and hypothyroidism could all contribute to nerve compression symptoms. Physical exams are used to isolate nerve compressions, with a focus on spotting any anatomical factors like the presence of masses (like lipomas, fibromas, or ganglion cysts) or blood clots. The remainder of this article describes various nerve compression syndromes and their symptoms in more detail.
The carpal tunnel syndrome is a common type of nerve injury that occurs when there’s pressure on the median nerve in the hand and wrist. This can be caused by constant use of the hands or by conditions like obesity, diabetes, pregnancy, and hypothyroidism. Patients often describe sensations of numbness, pins and needles, and pain that becomes worse at night. The hand may feel weak and clumsy, making it difficult to grip and grasp objects. Through a physical examination, carpal tunnel syndrome can be distinguished from similar conditions like pronator syndrome and cervical radiculopathy. Sensory symptoms typically involve the thumb, index, long, and lateral halves of the ring finger.
- Tinel sign (the doctor gently taps on the median nerve at the carpal tunnel to elicit a shock-like sensation)
- Phalen test (the wrist is flexed for 60 seconds, positive result includes numbness or a pins and needles sensation in the median nerve distribution)
- Carpal tunnel compression test (if symptoms present when pressure is applied over the carpal tunnel for 30 seconds, it’s a positive result)
- Flick sign (when a patient wakes up with symptoms and instinctively shakes their hand to relief them, it’s a positive sign of carpal tunnel syndrome)
Note that these tests have varying levels of sensitivity and specificity – meaning that they are not 100% accurate.
Ulnar neuropathy, or ulnar tunnel syndrome, can occur due to various reasons such as the formation of a ganglion, lipoma, tumors, fractures of the carpal bones, and external pressures (like using a screwdriver, bicycle, or wheelchair). This type of neuropathy occurs when the ulnar nerve is compressed at three zones. Zone 1 and Zone 2 compressions can lead to motor and sensory symptoms while Zone 3 compression mainly causes sensory disturbances.
- Froment sign (patients try to hold a piece of paper between their index finger and thumb while the doctor attempts to pull it away; a positive sign is seen if the thumb hyperflexes)
- Wartenberg sign (the little finger is abducted due to weakness of the palmar interosseous muscle)
The last condition, known as Wartenberg syndrome or cheiralgia parestheica, is quite rare. It results from compression of the radial nerve at the hand and wrist and usually presents as pain, tingling, or paresthesias on the dorsal side (back) of the wrist, hand, and fingers. The pain is often provoked by wrist movements, especially repetitive wrist flexion and ulnar deviation (bending the wrist towards the little finger).
- Tinel sign (the doctor lightly taps over the course of the superficial branch of the radial nerve which causes pain and/or parethesias)
- Dellon test (performed with forceful hyperpronation of the forearm and ulnar flexion of the wrist, which leads to pain)
Note that all these tests help in diagnosis, but aren’t always definitive as several conditions can have similar symptoms.
Testing for Hand Nerve Compression Syndromes
When a doctor needs to check for nerve compression syndromes, there are several methods they might use to do so. Here are a few examples:
Electrodiagnostic studies, like electromyography and nerve conduction studies, help to show which nerve is affected and where it’s being affected along its path. These tests can be used as a reference point for future comparisons as the treatment progresses. It’s important to understand that having normal results on these tests doesn’t necessarily rule out nerve compression. Your doctor will need to consider your medical history and any physical symptoms you’re experiencing.
Plain X-rays can be useful if there’s a history of injury or if there’s a suspicion of a broken bone. X-rays can also help to identify cases of osteoarthritis, bony growths or spikes, and medical devices inserted into the body that might be compressing nerves.
Magnetic Resonance Imaging (MRI) can help in detecting fluid-filled sacs (ganglion cysts), enlargement of synovial or muscle tissue, fluid buildup (edema), and blood vessel disease, as well as changes in the nerve. MRIs also allow doctors to measure the space for the nerve and compare it to what’s considered normal.
Ultrasonography, or ultrasound, has become increasingly popular because it can measure the width and length of the nerve. It can also detect abnormalities that may be compressing the nerve. Ultrasounds can also check if there is local fluid buildup (edema). Moreover, ultrasound may help distinguish between different causes of wrist pain, such as tendonitis or osteoarthritis.
Blood tests do not specifically diagnose nerve compression; however, they may be needed for other health conditions that could either cause nerve compression or mimic their symptoms. These conditions include diabetes and hypothyroidism. Tests that evaluate fasting blood sugar, hemoglobin A1c, or thyroid function may be helpful in managing your overall health. Other conditions that could mimic symptoms of nerve compression include vitamin B12 or folate deficiency, vasculitides (a group of disorders characterized by inflammation of the blood vessels), and fibromyalgia (a condition causing pain, fatigue, and sleep problems).
Treatment Options for Hand Nerve Compression Syndromes
Treatment for nerve compression syndromes – conditions where a nerve is squeezed or compressed – can be divided into non-surgical and surgical methods.
Non-surgical treatment
Most of the time, you can manage nerve compression without needing surgery. First, it’s good to avoid using the affected limb too often, and to change any wrist movements that might be causing symptoms. You might need to adjust how you go about your daily activities or work duties. It’s also beneficial to lose weight and engage in aerobic activity as being overweight might lead to nerve compression.
Wearing wrist splints can also help as these can minimize movements that worsen symptoms. It’s often recommended to wear these splints at night or during activities that usually result in symptoms. However, it’s not usually suggested to wear them all day as this can cause the wrist to become stiff. The duration of wearing a wrist splint can vary, ranging from as short as one week to as long as twelve weeks.
Non-steroidal anti-inflammatory drugs can be used to lessen inflammation and alleviate symptoms. Physical therapy or hand therapy can also be beneficial as it helps release tightness in muscles and reduces swelling. In cases where the above treatments aren’t working, a corticosteroid injection could be an option. These injections not only help treat nerve compression syndromes but can also be used to confirm the diagnosis and predict whether or not surgery would be effective. Having one corticosteroid injection can moderately improve symptoms. For instance, one injection helped improve the symptoms of carpal tunnel syndrome (a common nerve compression syndrome) in 76% of patients after six weeks. However, the relief is often temporary, with only 22% of patients remaining symptom-free after a year.
It’s also important for you to receive treatment for any other medical conditions that could worsen or cause nerve-compression syndromes.
Surgical treatment
If non-operative treatments don’t work, surgical decompression could be a consideration. Non-operative treatments are usually attempted for at least three months before considering surgery. During surgical decompression, the surgeon identifies the affected nerve and frees it from any structures (like scar tissue or fascial bands) that might be compressing it. The surgeon might also remove any soft tissue masses pressing on the nerve. Surgery can be considered as the first choice of treatment when the nerve compression is caused by injury or medical devices placed in the body during previous surgeries.
What else can Hand Nerve Compression Syndromes be?
When doctors are evaluating issues with the hand and wrist, like nerve compression, they must think about several factors. Firstly, they need to look at things that could be causing problems further up the arm, not just in the hand and wrist. Also, they have to think about any structures in the area that might be contributing to the problem.
Here are some specific things they might consider in different situations:
When dealing with Carpal Tunnel Syndrome, they might check for these issues:
- An issue with the front bone in the forearm causing nerve compression
- Inflammation in the tendons that bend the fingers (flexor tendonitis)
- A condition causing pressure on the nerve in the forearm (pronator syndrome)
- Arthritis in the wrist
For all hand and wrist problems, they would generally also consider things like:
- Brachial plexopathy – a condition affecting nerves in the neck and shoulder
- Issues with the neck nerves or spinal cord (Cervical radiculopathy or myelopathy)
- Compartment syndrome – a painful and dangerous condition caused by pressure buildup from internal bleeding or swelling of tissues
- Bodywide pain and tenderness (Fibromyalgia)
- Nerve diseases like amyotrophic lateral sclerosis
- Pressure on nerves as they pass through the shoulder (thoracic outlet syndrome)
- Blood vessel inflammation and cold-induced narrowing of the arteries (Vasculitis and Raynaud phenomenon)
- Deficiency in crucial vitamins
When the concern is Ulnar Tunnel Syndrome, they might consider:
- Pressure on the ulnar nerve at the elbow (Cubital tunnel syndrome)
- Inflammation of wrist tendon (extensor carpi ulnaris tendonitis)
- Fracture of the hook of the hamate – a small bone in the wrist
- A tear in a piece of cartilage in the wrist joint (triangular fibrocartilage complex (TFCC) tear)
And, when they suspect Wartenberg’s syndrome, they may think about:
- Inflammation of the tendons in the thumb (De Quervain tenosynovitis)
- Intersection syndrome – an inflammation of the thumb side of the forearm
- Irritation or inflammation of a nerve in the forearm (Lateral antebrachial cutaneous nerve neuritis)
What to expect with Hand Nerve Compression Syndromes
Carpal tunnel syndrome often gets worse over time. However, the severity of the symptoms can vary from week to week. Those with a mild case of carpal tunnel syndrome often see improvements with non-invasive treatments. Interestingly, about 80% of patients experience a reduction in symptoms after receiving a corticosteroid injection, which helps to decrease inflammation. Despite this, only about 22% remain free of symptoms after a year. Also, if an injection doesn’t provide relief, it may indicate surgery won’t be as effective.
When it comes to surgery for carpal tunnel syndrome, successful outcomes vary between 70 and 90% in terms of alleviating symptoms a year post-surgery. The rate of persistent symptoms after surgery varies between 2 to 20% depending on how severe the condition was at the outset.
Next, we have ulnar tunnel syndrome, a rare nerve disorder. There isn’t much data about the outcomes of the treatment for this condition. Less severe cases can sometimes be managed with non-invasive treatments. However, surgery is typically the best option for severe cases, especially when there’s an identifiable mass or lesion causing pressure on the nerve. The results reported from a few case studies have been positive, but we need more large-scale comparison studies to know for sure.
Finally, there’s Wartenberg syndrome. Many patients’ symptoms resolve spontaneously, and around 71% of them report excellent results from non-invasive treatments. Surgical outcomes are more varied. One study reported up to 74% success rate, while another noted that 55% of patients operated on still had symptoms 3.5 years after the surgery.
Possible Complications When Diagnosed with Hand Nerve Compression Syndromes
Complications may arise from both non-surgical and surgical treatments. If not treated surgically, conditions may worsen, or muscles may shrink and stiffen. However, surgery can have its share of complications too. They might include unsuccessful or incomplete surgery, persistence or recurrence of symptoms, symptoms getting worse, accidental nerve damage, formation of nerve tumors, formation of blood clots, and damage to surrounding body parts.
Common complications:
- Progression of symptoms
- Muscle atrophy
- Stiffness
- Unsuccessful or incomplete surgery
- Persistent symptoms
- Recurrence of symptoms
- Worsening symptoms
- Accidental nerve injury
- Formation of nerve tumors
- Formation of blood clots
- Damage to nearby body parts
Preventing Hand Nerve Compression Syndromes
Hand conditions caused by nerve compression, which feel like a pinched nerve, can often be effectively managed with non-surgical approaches. It’s really important to address any other health issues that could be contributing to these symptoms. Once the healthcare team knows what’s causing the problem, they will guide the patient on how to adjust their activities and avoid unnecessary strain which could make their symptoms worse.
If the symptoms continue, even after taking these precautions or after non-surgical treatments, surgery is another option that might help the patients feel better. Added to this, there are also educational materials provided by health organizations that both doctors and patients can use to help improve the treatment results. This includes resources from professional associations like the American Academy of Orthopedic Surgeons and the American Academy of Neurology, that are known for their expertise and are trusted sources of information. Therefore, patients can also use these resources to learn more about their condition.
