Carpal Tunnel: What Causes It?

Ever heard of carpal tunnel syndrome? Chances are, you probably have, and maybe you’ve even wondered, what causes carpal tunnel? You’re not alone; it’s incredibly common, affecting everyone from office workers to some of your favorite celebrities.

But what exactly leads to carpal tunnel syndrome? Let’s dive into what’s really going on behind the scenes in your wrist and why this condition is more common than you might think.

What is the carpal tunnel?

The “carpal tunnel” is a narrow passageway in your wrist, made up of bones and a stout ligament that the median nerve (and your finger flexor tendons) passes through.

 

The “syndrome” of Carpal tunnel syndrome is the numbness and tingling (or pins and needles) in your fingertips, and occasionally hand pain, which occurs mainly at night time. It is a condition that originates with the median nerve in your wrist, which runs from your shoulder to your hand. It's for this reason that the medical term is called "median nerve entrapment". 

When this tunnel gets too crowded (usually because of swelling or inflammation), your nerve gets squeezed, the blood flow decreases, and that’s when the trouble starts. Numbness, tingling, and pain in your hand and fingers are all telltale signs. 

It’s not just a little discomfort; it can get in the way of your daily activities. Typing, driving, holding a coffee cup, or even sleeping can become a challenge. So, while it might start as a slight annoyance, carpal tunnel syndrome can turn into a major hassle if left unchecked.

What are the symptoms of carpal tunnel?

So, how do you suspect that you even have carpal tunnel? The first indicator is always the symptoms. The most common ones are:

• Numbness and Tingling: This usually starts in the thumb, index, middle, and part of the ring finger, making it feel like your hand “falls asleep” more often than not. The pinky is not involved, although it is not always easy for a patient to realize this.
• Pain: You might experience sharp or burning pain in your wrist and hand, sometimes extending up to your elbow. Carpal tunnel pain is usually not felt from the neck moving towards the hand. In addition, the thenar muscles in the base of the thumb, on the palm of your hand may also ache.
• Weakness: Dropping objects or struggling with grip strength can become common as your hand and thumb muscles weaken.
• Swelling Sensation: Even if there’s no visible swelling, your fingers may feel swollen or puffy. Some patients even say their fingers feel cold.
• Worsening Symptoms at Night and Driving: Symptoms often intensify at night and driving due to the position of the wrist. This can disrupt sleep and cause you to wake up needing to shake out your hand.

If you’re experiencing some of these symptoms, combined with exposure to common causes, you might be suffering from carpal tunnel syndrome.

What causes carpal tunnel?

Median nerve entrapment can be caused by a combination of activities, risk factors, and even your occupation.

Some of the most common causes are:

• Prolonged Wrist Positioning: Holding your wrist in awkward positions for extended periods, like when driving or sleeping, can put pressure on the median nerve. The two most common activities are sleeping (in the fetal position with your wrist flexed and the back of your hand next to your face) as well as driving (with your wrist extended all the way). These extreme positions pinch the nerve, decrease blood flow, and then numbness and tingling starts. Do this long enough and the nerve starts to get irritated and covered in inflammation which starts to crush the nerve even without extreme positioning.
• Repetitive Hand Movements: Activities like typing, using a mouse, or texting are big culprits. Modern technology, with its constant demand for keyboard and smartphone use, has made this condition more prevalent. However, the exact way these repetitive movements cause carpal tunnel are not well understood as some activities cause worse symptoms than others. The cause-and-effect with repetitive movements is not always clear-cut.
• Professions at Risk: Jobs that require repetitive hand use, like assembly line work can cause this. Vibrating instruments, like an orbital sander and an impact driver, are known causes of carpal tunnel syndrome. Musicians and hairdressers also commonly suffer from carpal tunnel due to repetitive hand and wrist positioning.
• Health Conditions: Conditions like diabetes, rheumatoid arthritis, and obesity increase the risk by causing inflammation or restricting blood flow to the median nerve. Amyloidosis (protein deposition) can also contribute to the development of carpal tunnel syndrome.
• Gender and Age: Women and older adults are more likely to develop carpal tunnel, possibly due to smaller carpal tunnels or hormonal changes.

So, if you have both the symptoms and are exposed to one of the risks, chances are that it’s actually carpal tunnel. If knowing what causes carpal tunnel isn’t enough, there’s one more way to tell if you have carpal tunnel syndrome - testing.

Carpal tunnel syndrome tests

There are actually a few tests you can conduct to see if you really have carpal tunnel syndrome.

One of the most common tests is called the Phalen’s test. It’s super simple: you just press the backs of your hands together with your fingers pointing down like you’re doing a reverse prayer. Hold this position for about a minute. If you start feeling that familiar tingling, numbness, or pain in your fingers, that is a positive test for carpal tunnel syndrome.

Another test doctors use is the Tinel’s sign. This one involves your doctor tapping lightly over the median nerve at your wrist. If it sends a little electric shock sensation down your fingers, that’s another clue.

These tests are quick, non-invasive, and give doctors a pretty good idea of what’s going on. If you’re experiencing symptoms, they might be your first step toward getting some relief!

What is the treatment for carpal tunnel syndrome?

 “Carpal tunnel syndrome is the most common condition I treat as a hand surgeon. I customize the treatment based on the patient’s severity and interests. For some, it is an annoyance which can dissipate with conservative care; however, others need surgery to lessen the chance of permanent nerve damage.” - Dr. Christian Zaino

When it comes to treating carpal tunnel syndrome, most people start with conservative methods. These are the go-to options before thinking about anything more serious. The best 3 treatments are splinting, steroid injections, and surgery.

Wrist splints are often recommended, especially at night, to keep your wrist in a neutral position and relieve pressure on the median nerve. So, you cannot longer pinch your nerve during your fetal position sleep.

Over-the-counter pain relievers like ibuprofen can help reduce inflammation and ease discomfort. However, the success with this method is minimal.

Some people also find relief with steroid injections, which can reduce swelling and improve symptoms temporarily. This is usually very helpful, but may not solve the problem. Besides treating the patient, success with a steroid injection can confirm the diagnosis (sometimes things aren’t clear) and it gives a good prognosis for how well surgery may or may not help you.

And let’s not forget lifestyle changes—taking breaks from repetitive tasks, stretching your hands, and adjusting your workstation can make a big difference. Limit use of vibrating instruments too.

But sometimes, conservative treatments just don’t cut it. That’s when carpal tunnel surgery might come into play. Surgery is usually considered if you’ve been dealing with severe symptoms for a while and they’re affecting your daily life.

The procedure, called carpal tunnel release, involves cutting the ligament that forms the roof of the carpal tunnel to relieve pressure on the median nerve. It’s a relatively simple surgery with a good success rate, but like any surgery, it comes with recovery time and some risks. Most people find significant relief after surgery, especially if their symptoms are severe.

Wrap up

So, what is carpal tunnel?

It’s a hand condition that can be incredibly painful and restrictive. Worst of all, it’s becoming more and more common due to the exposure to modern technology and the hand movements it requires (not to mention the incredible repetitiveness of these motions).

Therefore, learning how to recognize and treat carpal tunnel may become an essential life skill in the modern era.

Learn more about the causes of carpal tunnel syndrome and discover your treatment options at the Orthopedic Institute of NJ today!