Carpal Tunnel Syndrome

Carpal tunnel syndrome is caused by pressure on a nerve in your wrist. This most commonly causes tingling, numbness, pain, and weakness in your hand. Carpal tunnel syndrome can sometimes get better on its own. But there are also treatments that can help.

What is carpal tunnel syndrome?

• Carpal tunnel syndrome is when a nerve, called the median nerve, in your wrist, becomes compressed (squeezed). This nerve controls the feeling in your thumb, index, middle, and ring fingers. It also controls muscles in your thumb. When it’s compressed, it leads to the symptoms of numbness, tingling, pain, and weakness.
• Your median nerve runs through a narrow channel in your wrist called the carpal tunnel. The channel is formed from your wrist bones and a tough band of tissue known as the transverse carpal ligament, which is on the top. Anything that reduces the space or increases the pressure in your carpal tunnel can cause carpal tunnel syndrome.
• Carpal tunnel syndrome affects people of all ages but is more common over the age of 50. Women are more likely to develop it than men.

?The parts of this tunnel include:

Carpal bones:

• These bones make up the bottom and sides of the tunnel. They are formed in a semi-circle.

Ligament:

• At the top of the tunnel, the ligament is a strong tissue that holds the tunnel together.

Inside the tunnel are the median nerve and tendons.

Median nerve:

• This nerve provides feeling to most of the fingers in the hand (except the little finger). It also adds strength to the base of the thumb and index finger.

Tendons:

• Rope-like structures and tendons connect muscles in the forearm to the bones in the hand. They allow the fingers and thumb to bend

Does carpal tunnel syndrome only happen to office workers or factory workers?

No. Many people with carpal tunnel syndrome have never done office work or worked on an assembly line. It affects people who use their wrists and hands repeatedly at work and at play. Anyone can get carpel tunnel syndrome, but it is unusual before age 20. The chance of getting carpal tunnel syndrome increases with age.

Who is at risk for carpal tunnel syndrome?

People at risk for carpal tunnel syndrome are those who do activities or jobs that involve repetitive finger use. Motions that can place people at risk of developing carpal tunnel syndrome include:

• High-force (hammering).
• Long-term use.
• Extreme wrist motions.
• Vibration.

Many other factors can also contribute to the development of carpal tunnel syndrome. These factors can include:

• Heredity (smaller carpal tunnels can run in families).
• Pregnancy.
• Hemodialysis (a process where the blood is filtered).
• Wrist fracture and dislocation.
• Hand or wrist deformity.
• Arthritic diseases such as?rheumatoid arthritis?and?gout.
• Thyroid gland hormone imbalance (hypothyroidism).
• Diabetes.
• Alcoholism.
• A mass (tumor) in the carpal tunnel.
• Older age.
• Amyloid deposits (an abnormal protein).

Carpal tunnel syndrome is also more common in women than in men.

SYMPTOMS AND CAUSES

Carpal tunnel syndrome is caused when the space (the carpal tunnel) in the wrist narrows. This presses down on the median nerve and tendons (located inside the carpal tunnel), making them swell, which cuts off sensation in the fingers and hand.

Causes of carpal tunnel syndrome

Carpal tunnel syndrome is caused by the compression of a nerve in your wrist called the median nerve. There are lots of reasons why this may happen and it’s often difficult to identify one specific cause. It’s likely to be due to several factors. The following can make you more likely to develop it:

• being overweight
• having certain other health conditions including?diabetes?or an?underactive thyroid
• pregnancy – this may be due to the associated hormonal changes and fluid retention
• injury to your wrist such as a wrist fracture
• doing repeated activities that put your wrist in an unnatural position – either very flexed or extended (bent either forwards or backward)
• some inflammatory conditions such as?rheumatoid arthritis
• a tumor or growth which might press on your nerve or make your carpal tunnel narrower

Symptoms of carpal tunnel syndrome

Carpal tunnel symptoms tend to affect your thumb and fingers (apart from your little finger). Symptoms include:

• numbness
• a tingling feeling or pins and needles
• weakness and finding it difficult to grip
• pain or a burning feeling

You can have carpal tunnel symptoms in both hands or just one. It can start to affect your whole hand and may also spread up your arm. Your symptoms may be mild at first, but they may gradually get worse. You can get carpal tunnel symptoms at any time but they’re often worse at night and may wake you up. Certain activities may also trigger your symptoms during the day.

Your carpal tunnel syndrome symptoms may feel better if you shake your wrist or change its position.

If you have any of these symptoms, contact your GP for advice.

How often is hand pain caused by carpal tunnel syndrome?

While carpal tunnel syndrome is a common condition, it has a different set of symptoms from many other sources of hand pain. There are actually several similar conditions that cause hand pain. These include:

• De Quervain’s tendinosis: A condition where swelling (inflammation) affects the wrist and base of the thumb. In this condition, you will feel pain when you make a fist and simulate shaking someone’s hand.
• Trigger finger: This condition causes soreness at the base of the finger or thumb. A trigger finger also causes pain, locking (or catching), and stiffness when bending the fingers and thumb.

• Arthritis: This is a general term for many conditions that cause stiffness and swelling in your joints. Arthritis can impact many joints in your body and ranges from causing small amounts of discomfort to breaking down the joint over time (osteoarthritis?is one type of degenerative arthritis).

Diagnosis of carpal tunnel syndrome

First, your doctor will discuss your symptoms, and medical history and examine you. Next, tests are performed, which may include:

• Tinel’s sign: In this test, the physician taps over the median nerve at the wrist to see if it produces a tingling sensation in the fingers.
• Wrist flexion test (or Phalen test): In this test, the patient rests his or her elbows on a table and allows the wrist to fall forward freely. Individuals with carpal tunnel syndrome will experience numbness and tingling in the fingers within 60 seconds. The more quickly symptoms appear, the more severe the carpal tunnel syndrome.
• X-rays:?X-rays of the wrist?may be ordered if there is limited wrist motion or evidence of arthritis or trauma.
• Electromyography (EMG)?and nerve conduction studies: These studies determine how well the median nerve itself is working and how well it controls muscle movement.

How is carpal tunnel syndrome treated?

Carpal tunnel syndrome can be treated in two ways: non-surgically or with surgery. There are pros and cons to both approaches. Typically, non-surgical treatments are used for less severe cases and allow you to continue with daily activities without interruption. Surgical treatments can help in more severe cases and have very positive outcomes.

Non-surgical treatments

Non-surgical treatments are usually tried first. Treatment begins by:

• Wearing a wrist splint at night.
• Taking?nonsteroidal anti-inflammatory drugs, such as ibuprofen.
• Cortisone injections.

Other treatments focus on ways to change your environment to decrease symptoms. This is often seen in the workplace, where you can make modifications to help with carpal tunnel. These changes might include:

• Raising or lowering your chair.
• Moving your computer keyboard.
• Changing your hand/wrist position while doing activities.
• Using recommended splints, exercises, and heat treatments from a hand therapist.

Surgical treatments

Surgery is recommended when carpal tunnel syndrome does not respond to non-surgical treatments or has already become severe. The goal of surgery is to increase the size of the tunnel in order to decrease the pressure on the nerves and tendons that pass through the space. This is done by cutting (releasing) the ligament that covers the carpal tunnel at the base of the palm. This ligament is called the transverse carpal ligament.

If you have surgery, you can expect to:

• Have an outpatient procedure where you will be awake, but have?local anesthesia?(pain-numbing medication). In some cases, your doctor may offer an IV (directly into the vein) anesthetic. This option allows you to take a brief nap and wake up after the procedure is finished. This is not a general anesthetic, like what is used in surgery. Instead, your healthcare team will monitor you during the procedure (called monitored anesthetic care, or MAC). This is also used for procedures like a colonoscopy.
• Be in brief discomfort for about 24 to 72 hours after surgery. People usually experience complete nighttime symptom relief quickly—even the night after surgery.
• Have your stitches removed 10 to 14 days after surgery. Hand and wrist use for everyday activities is gradually restored by using specific exercise programs.
• Be unable to do heavier activities with the affected hand for about four to six weeks. Recovery times can vary depending on your age, general health, the severity of carpal tunnel syndrome, and how long you had symptoms. You will continue to gain strength and sensation in the following year after surgery.
• Have relief from most carpal tunnel syndrome symptoms.

Self-help for carpal tunnel syndrome

There may be things you can do to manage your symptoms. If there are particular activities that seem to trigger your symptoms, try to avoid these if you can. It may help if you change the way you do these actions or reduce how often you do them. If you’re overweight,?losing any excess weight?may help to reduce your symptoms.

If you find your symptoms are worse at work, talk to your manager or occupational health department if you have one. They may be able to help with modifications to your workplace or a temporary change to your duties. For example, they may be able to give you a different style of keyboard or provide you with some wrist rests that can help.

Treatment of carpal tunnel syndrome

You don’t always need treatment for carpal tunnel syndrome. For some people, the symptoms improve on their own within about six months. This is more likely if you’re under 30, and especially if your symptoms are due to pregnancy.

Treating any underlying condition such as arthritis may improve your carpal tunnel symptoms.

Wrist splints for carpal tunnel syndrome

Wrist splints can help to keep your wrist straight and reduce pressure on your compressed nerve. This can help with night-time symptoms in particular. Your doctor will usually advise you to wear wrist splints at night for at least six weeks. You can also wear splints during the day, but you may find that they get in the way as you go about your daily routines.

You can buy a wrist splint online or from a pharmacy.

Steroid injections for carpal tunnel syndrome

Your GP may offer you a steroid injection into your carpal tunnel to help relieve your pain. You may be able to have this at your GP surgery or they may need to refer you to a specialist for the treatment.

Steroid injections work well for many people but it can take a few weeks to get the full effects. They don’t work for everyone. They can also wear off after a while and your symptoms may come back. If your symptoms do return, you may be able to have a repeat injection but it’s not always effective.

Carpal tunnel surgery

If your symptoms are severe or other treatments haven’t worked, your GP may refer you to a hand specialist or local musculoskeletal service. They will assess you to see if carpal tunnel surgery (also called?carpal tunnel release surgery) would be an option.

Carpal tunnel surgery is usually carried out as a day case, under?local anesthesia. This means you’ll have the procedure and go home on the same day. The area will be numb so you don’t feel any pain. The procedure involves dividing the ligament in your wrist that forms part of your carpal tunnel. This will relieve pressure on your median nerve. It’s generally very effective and has a high success rate. Up to nine in 10 people find that their symptoms improve. As with all surgery, there are some risks involved. There’s also a chance that your symptoms may come back after surgery. It’s important to talk this over with your doctor before you decide whether or not surgery is the right choice for you.

Other carpal tunnel syndrome treatments

Exercise therapy

Some people find that hand and wrist exercises can help with carpal tunnel syndrome symptoms. If you see a?physiotherapist, they may recommend some of these exercises. Some are simple exercises to improve the strength and flexibility in your wrist. Others, known as nerve glide exercises, specifically aim to help your trapped nerve move more freely. There isn’t much good evidence to show that these exercises help though. You shouldn’t do any activity that makes your symptoms worse.

Complementary therapies

Some people find acupuncture helps to relieve the symptoms of carpal tunnel syndrome. But there’s not enough evidence to say for sure that it works.

Some people also find that yoga helps to relieve pain associated with carpal tunnel syndrome. But again, more research is needed to know for sure.

If you decide to try complementary therapy, check that your therapist is registered with a recognized organization.

Can carpal tunnel syndrome return?

Yes. Although carpal tunnel can get better by itself or may go away with treatment, it’s possible for symptoms to come back again. Steroid injections may only work for a limited time. And symptoms may also come back after surgery. Talk to your doctor if your symptoms have come back again. They may suggest further investigations and other treatments.

Why is carpal tunnel syndrome worse at night?

At night, you’re more likely to bend your wrist without realising. This increases the pressure on your nerve as it passes through your carpal tunnel, leading to more symptoms. This is why wearing a splint at night is one of the first things that’s usually advised. A splint will keep your wrist in a neutral position, so you can’t bend it.

Do I have carpal tunnel syndrome or arthritis?

Both osteoarthritis and carpal tunnel syndrome can cause symptoms in your hand and wrist. It’s common to have both carpal tunnel syndrome and osteoarthritis. But with osteoarthritis, you’re more likely to have painful, swollen or stiff joints around your wrist. Pain and swelling will just be in the affected joint. You may notice grating, cracking or popping sensations around your wrist when you move it. You may also find it difficult to grip things or to lift heavy objects.

Carpal tunnel syndrome is more likely to cause a tingling sensation around your hand. You won’t usually be able to see any physical signs. And the discomfort won’t be in such a specific area as when you have osteoarthritis. For more information about carpal tunnel symptoms, see our section on symptoms above.

A note from Dr.Shady Abdel Mohsen?

Carpal tunnel syndrome

INTRODUCTION

• Carpal tunnel syndrome is one of the most common peripheral neuropathies. It affects mainly middle-aged women due to compression of the median nerve in the carpal tunnel
• The risk of CTS is high in occupations involving exposure to high pressure, high force, repetitive work, and vibrating tools
• The acute form is relatively uncommon and is due to a rapid and sustained rise of pressure in the carpal tunnel. This is most commonly associated with a fracture of the radius
• The chronic form is much more common and symptoms can persist for months to years Carpal tunnel syndrome is common in pregnant women

AETIOLOGY

A. Local causes

• ?Inflammatory: e.g. tenosynovitis, Histoplasma fungal infection, hypertrophic synovium
• Trauma: e.g. Colles' fracture, dislocation of one of the carpal bones
• Tumors: e.g. Haemangioma, cyst, ganglion, lipoma, neuroma, etc.
• Anatomical anomalies: e.g. thickened transverse carpal ligament, bony abnormalities, abnormal muscle bellies, persistent median artery, etc.

B. Regional causes

• Osteoarthritis
• Rheumatoid arthritis
• Amyloidosis
• Gout

C. Systemic causes

• Diabetes
• Obesity
• Hypothyroidism
• Pregnancy
• Menopause
• Systemic lupus erythematosus
• Scleroderma
• Dermatomyositis
• Renal failure
• Long-term hemodialysis
• Acromegaly
• Multiple myeloma
• Sarcoidosis
• Leukaemia
• Alcoholism
• Haemophilia

PATHOPHYSIOLOGY

The most popular ones are mechanical compression, micro-vascular insufficiency, and vibration theories.

CLINICAL FEATURES

The most common symptom is burning pain associated with tingling and numbness in the distribution of the median nerve distal to the wrist. The portion of the hand involved is classically the thumb, index and middle fingers, and radial half of the ring finger.?

SIGNS

• Tinel's sign & Phalen's test
• Pressure provocation test

DIAGNOSIS

• The nerve conduction studies (NCS) measure the sensory and motor nerve conduction velocity in the median nerve at the level of the wrist

TREATMENT

• The various non-surgical methods include: the use of a hand brace, splinting of the wrist, ultrasonic therapy, laser therapy, oral steroids, non-steroid anti-inflammatory drugs (NSAIDs), oral vitamin B6, local injection of corticosteroids
• Surgery consists of the division of the transverse carpal ligament. This reduces the pressure on the median nerve by increasing the space in the carpal tunnel. Surgery is indicated in almost all patients with moderate to severe CTS
• ?The gold standard test is nerve conduction studies
• The diagnosis of CTS should be based on history, physical examination, and results of electrophysiological studies
• The patient with mild symptoms of CTS can be managed with conservative treatment, particularly local injection of steroids. However, in moderate to severe cases, surgery is the only treatment that provides a cure

Surgery

• The basic principle of surgery is to increase the volume of the carpal tunnel by dividing the transverse carpal ligament to release the pressure on the median nerve
• Surgery consists of a division of the transverse carpal ligament. This reduces the pressure on the median nerve by increasing the space in the carpal tunnel. Surgery is indicated in almost all patients with moderate to severe CTS. An absolute indication for CT release (CTR) is muscular atrophy Two different types of surgical approaches are in use for the treatment of CTS; open and endoscopic release. Open CTR (OCTR) is the traditional option and still the recommended method of surgical treatment for idiopathic CTS. It was first performed by Herbert Galloway in 1924, though since then several modifications have been made to refine it. The classic OCTR uses a curved longitudinal inter-thenar incision, approximately 4 to 5 cm in length. It involves the opening of subcutaneous tissue, superficial fascia, transverse carpal ligament, and 2 to 3 cm of distal forearm fascia under direct vision. The canal was also inspected for mass lesions and anatomical abnormalities.

• The well-recognized early complications are the incomplete release of TCL, neuropraxia or injury to the median or ulnar nerve, inadvertent entry to Guyon's canal (the tunnel between the pisiform and hamate bone and the ligament connecting both bones), injury to the palmar cutaneous or recurrent motor branch of the median nerve and injury to the superficial palmar arch or ulnar artery. These complications are rare as surgery is performed under direct vision. The late complications are scar tenderness, loss of grip strength, pillar pain, and rarely reflex sympathetic dystrophy and bowstringing of flexor tendons. Pillar pain is a frequent complication of both open and endoscopic release procedures
• As in other fields of surgery, less invasive techniques have been introduced into carpal tunnel surgery to facilitate earlier return to work and reduce post-operative pain and the first endoscopic carpal tunnel release was performed by Okutsu and his colleagues in Japan in 1987. Since its introduction, several modifications of the technique have been described in the literature. There are several endoscopic approaches but the underlying principle is the same; to release the transverse carpal ligament. ECTR techniques can be broadly divided into single-portal and dual-portal techniques depending on the number of ports used to access the carpal tunnel. The two most commonly used techniques are the single-portal technique described by Agee?and the two-portal technique described by Chow. It is beyond the scope of this review to go into detail about each technique. The reported success rates for surgical treatment range from 70 to 90%

CONCLUSIONS

• Surgery is the only treatment that provides a cure in moderate to severe cases. Apart from early recovery and return to work there is no difference in the early and late complications and the outcome between open and endoscopic surgical decompression.

REFERENCES:

1.?Eversmann WW., Jr . Entrapment and compression neuropathies. In: Green DP, editor.?Operative hand surgery vol 2.?New York: Churchill Livingstone; 1993.

pp. 1341–85.

Blanc PD, Faucett J, Kennedy JJ, Cisternas M, Yelin E. Self-reported carpal tunnel syndrome: predictors of work disability from the National Health Interview Survey Occupational Health Supplement.?Am J Ind Med.?1996;30(3):362–8.?