What is it?
Carpal tunnel syndrome (CTS) occurs when the median nerve is compressed as it travels through the carpal tunnel of the wrist. The carpal tunnel is the space between the forearm and wrist bones where the median nerve travels through; space holds its shape by the bone structure and the transverse carpal ligament.
When the carpal tunnel space is comprised by inflammation, compression, or a traumatic injury, the median nerve is compressed. Over time with repeated or sustained compression, symptoms of pain, numbness, and tingling appear in the hand because the nerve is irritated. Typically, CTS symptoms occur in the palm, thumb, index, and middle fingers.
To understand how compression of the median nerve happens, a basic understanding of the wrist anatomy is important. The forearm has two bones, ulna and radius, which meet up with the carpus bones, also known as the wrist. This juncture is where the carpal tunnel exists. The ulna is the largest of the pair of forearm bones. The top of the ulna is felt on the inside of the elbow. It runs down the forearm and ends at the wrist on the medial side (pinky finger).
The radius is smaller in size and starts on the outside of the elbow and runs down to the lateral side (thumb side) of the wrist. Despite the radius being overall smaller than the ulna, it does have the largest surface area of the two bones at the wrist.
Within each of our wrists, we have eight bones. These bones form two rows, the proximal and distal rows. The four proximal bones are the closest to the ulna and radius; the four bones in the distal row are closest to the metacarpal (hand) bones.
Ligaments are tough fibrous tissue connecting bones together to form a joint. The wrist has a large ligament called the transverse carpal ligament which runs perpendicular to the carpal space. The main goal of the transverse carpal ligament holds the wrist bones together, keep them compact. It just so happens the transverse ligament and bones within wrist form an opening, or tunnel, where the median nerve travels.
Within the hand, there are three main nerves: ulnar, radial, and median. The ulnar nerve affects the palm, little, and ring fingers. The radial nerve affects the backside of the hand. The median nerve, which is the culprit for CTS, affects the palm, thumb, index and middle fingers.
The carpal tunnel space within the wrist is narrow, about the size of the width of your thumb. With repetitive movements or sustained compression, this narrow space may swell. When swelling occurs, the median nerve is compressed and cannot appropriately communicate to the hand, which means numbness, tingling, and weakness settles in. Interestingly, women tend to have smaller wrists, therefore, are more susceptible to CTS.
A few basis CTS facts:
- Affects 1% of the American population, but occurs in about 5% of the American workforce.
- Number one cause for lost work days; almost half of CTS sufferers miss on average +31 working days
- $1 billion spent annually on direct medical costs for treatment of CTS
- Women are more likely than men to suffer from CTS
What causes carpal tunnel syndrome?
Multiple factors play a key role into why someone may develop carpal tunnel syndrome. Beyond trauma and repetitive motion, there are also a few health conditions that may attribute to the cause of CTS:
- Chronic kidney insufficiency
- Cyst or tumor
- Hereditary (e.g. structure of wrist is smaller)
- Hormone changes (e.g. menopause)
- Medications (e.g. steroids)
- Overactive pituitary gland (controls hormones)
There are also, of course, other causes for CTS, and they are:
- Bone fracture
- Compression of wrist (e.g. resting wrists on hard surface when keying)
- Exposure to repetitive or sustained vibration (e.g. hand tools)
- Poor mechanics of the wrist and forearm
- Sprain (ligament injury)
There are some jobs at higher risk for the cause of CTS development. The list below are a few examples of high-risk jobs and is not meant to be all-encompassing:
- Construction laborers
Those who suffer from carpal tunnel syndrome start off with mild wrist pain or aching. The thumb, index and middle fingers may ache, or they may have a tingling sensation. At this early stage, people report if they “shake it off” the symptoms go away.
As CTS progresses, the pain is more noticeable. In can feel like a deep ache or sharp pain within the wrist. The pain, tingling, and numbness tend to be worse at night, which is because of hand and wrist movements act like a pumping mechanism to keep the swelling down within the area. However, once we stop our activities, the swelling settles in as well the nerve and surrounding tissue become over irritated.
More advanced CTS causes weakness and numbness in hand. Often people will report a weak grip where they can’t open jars and the drop items all the time.
How is carpal tunnel syndrome diagnosed?
Carpal tunnel syndrome symptoms are clear, weakness, tingling, numbness and pain in the palm, thumb, and middle finger. If you have pain in the ring or little finger, that is the ulnar nerve and not related to CTS.
A health care professional, like a physical therapist (PT) or occupational therapist (OT), can complete an examination. First, your PT or OT will complete a full evaluation including reviewing your medical history, gathering information about the onset of symptoms, and completing a full physical evaluation.
The physical exam will include strength testing related to your grip and forearm muscles. Your PT or OT will also check out your neck strength and range of motion as this is where the three main nerves originate from in hands. In addition to checking muscle strength, he or she will assess your reflexes and sensory system.
Once the evaluation is complete, your PT or OT will establish a treatment plan with you. Together you will set goals, as well your PT or OT will provide you a prognosis with realistic expectations of conservative treatment.
In rare cases, if the PT or OT believes there are other medical conditions causing CTS, he or she will refer you to your physician. A battery of tests may be performed by your physician to rule out other serious medical causes. Diagnostic testing may include:
- X-Ray-rule out fractures, dislocations, and arthritis
- MRI (magnetic resonance imaging)-rule out other circulatory issues within the tunnel; confirm narrowed tunnel space
- Blood tests-rule out other underlying causes such rheumatoid arthritis or thyroid issues
- Nerve testing-determine the severity of nerve damage
When diagnosed and treated early, CTS responds well to conservative care like PT or OT. In PT or OT, the goal is to reduce the swelling, manage the symptoms, and return you to functional activities.
Swelling may be managed by cold treatment or ultrasound. For those who wake-up in the morning with your wrists curled in, night splints help prevent wrist flexion which is a big culprit to narrowing the carpal tunnel space. Your PT or OT will also instruction you on proper mechanics of the head, neck, shoulders, and hands. Addressing the body mechanics of the kinetic chain is critical to long-term success.
Along with inflammation management, wrist positioning, and body posture, addressing the cause of the symptoms is important too. Your PT or OT may make equipment recommendations for work to reduce compression and irritation of the wrist. Some recommendations may include wearing anti-vibration gloves, a gel wrist pad at the keyboard, or even teaching you how to take proper stretching breaks.
In the most severe cases of CTS, an injection may be needed to help reduce the localized inflammation and symptoms. An injection alone is never recommended as it is a band aid to the cause. PT or OT in conjunction with the injection treatment is highly recommended to maximize long-term results.
If CTS is advanced and non-responsive to rehabilitation or an injection, surgery may be indicated. With CTS, the surgeon cuts the transverse ligament to open the space and alleviate the compression on the median nerve.
Carpal tunnel release surgery is minimally invasive; however, there is still a recovery period. Most will need help with basic household chores and daily activities for two weeks. PT or OT is recommended after surgery to help with the safe progression of strengthening the area and returning to functional activities. The average peak recovery time from surgery is approximately 10-months post-surgery.
Early intervention to CTS symptoms is found to be successful. The sooner you address your symptoms, the more likely conservative care will work for you. As a consumer of health care, you have a choice in finding the right provider for you. Do your homework and search for a health care provider, like a physical therapist, with excellent outcomes, great customer reviews, and can provide you the care you need for a reasonable cost.
In most states, you can be seen by a PT first, without a physician’s order. To determine if your state has direct access, please visit the American Physical Therapy Association’s website Physical Therapy Direct Access By State.
To get started with conservative care today, you can find a highly qualified PT or OT in your area. There are many qualified PTs and OTs, so to find one near you, please click on Find A Clinic. This link will help you find a PT or OT that has top national rankings for treating CTS.