What causes Carpal Tunnel Syndrome?
Carpal Tunnel Syndrome also known as CTS is a very frequent injury that occurs due to the reduction in size of the carpal tunnel. As the median nerve is more sensitive to the structures (9-flexor tendons) within the tunnel, the symptoms described are usually related to the narrowing or collapsing of the carpal tunnel thus resulting in nerve compression. By definition carpal tunnel syndrome is a neuropathy caused by compression of the median nerve within the carpal tunnel .
Carpal Tunnel Syndrome occurs when any injury significantly reduces the diameter of the carpal tunnel. Infection, fluid retention, tendinitis, tenosynovitis, tumor, edema, etc., but in most cases, a muscle imbalance is present, causing the carpal tunnel to collapse and narrow due to weak finger and wrist extensor /abductor muscles not being able to hold the carpal bones in their normal position. If any structure that passes though the carpal tunnel increases in size, or the diameter of the carpal tunnel decreases in size, the structures within the tunnel will be "crushed" between the bony structures and the transverse carpal ligament, resulting in painful symptoms.
What is the Carpal Tunnel?
Above the flexor retinaculum (transverse carpal ligament or carpal annular ligament) is an arc made by two rows of carpal bones and inserts on the lateral tubercles of the scaphoid and trapezoid and medial hamate, hamulus and pisiform (Moore, 2001). Within this arc, the carpal “tunnel” is formed through which the nine flexor tendons and median nerve pass, spreading to the thumb, index, middle and one-half of the ring finger, which allows for movement and feeling of these fingers on the anterior (front) side of the hand.
What are the structures that pass through the carpal tunnel?
- Four superficial flexor tendons of the fingers
- Four tendons of the deep flexor muscles
- One flexor tendon of the thumb
- Median nerve
Who is Most-Likely to Develop Carpal Tunnel Syndrome?
Seventy percent of patients are between 40 and 70 years of age and women are affected three to five times more than men. Usually women do more manual labor than men, which increases the likelihood of muscle imbalance development and the recurrent tendinitis of the superficial flexor tendons, the deep flexor tendons and the flexor tendon of the pollicis longus due to increased friction of these tendons and median nerve as they move back and forth within the narrowing carpal tunnel. (The greater the muscle imbalance, the smaller the carpal tunnel becomes. Once the extensor muscles are strengthened to support and hold the carpal bones in their correct anatomical positions, the carpal tunnel returns to its correct size, thus reducing the friction of the flexor tendons within the carpal tunnel, thus eliminating the friction, swelling and resulting pressure on the median nerve that is the underlying source for the development of carpal tunnel syndrome.)
What is the Difference between Carpal Tunnel Syndrome and Guyon’s Canal / Tunnel Syndrome?
~ Guyon’s Canal Syndromehas the same characteristics of Carpal Tunnel Syndrome, but the affected nerve is the ulnar nerve and the site of compression is the Guyon's canal or tunnel. The symptoms described for this syndrome should then be related to the ulnar nerve and result in numbness, tingling, paresthesia, pain, etc. that affect the ring and little finger. (Note: The cause of Guyon’s Syndrome is often the same as that of Carpal Tunnel Syndrome as described above.)
~ Carpal Tunnel Syndrome is compression of the median nerve at the wrist junction within the carpal tunnel. Symptoms of numbness, tingling, pain, waking up at night, paresthesia (pins and needles) are the main symptoms that affect the thumb, index, middle and sometimes one-half of the ring fingers. More severe symptoms may include cyanosis in the first three fingers, reduction in muscle strength and atrophy of the involved muscle tissues, especially the thenar eminence (base of thumb).
So be informed before you see your doctor as you may have symptoms of Guyon’s Syndrome which they may diagnose as carpal tunnel syndrome and perform surgery for a condition that is non-existent.
What Treatments are Available?
~ Drug Therapy: The complete B vitamins especially B6, and anti-inflammatory and pain medications to control symptoms and maintain nerve health and conduction.
~ Surgical Treatment: When no conservative treatment eliminates the condition, then surgery is often indicated. The most common surgery performed is the “closed” procedure and involves the dissection of the transverse carpal ligament to increase space for the flexor tendons and median nerve to operate in without impingement.
~ Flextend Orthosis: Exercise system that corrects muscle imbalances in the fingers, hand and elbow by opening the carpal tunnel and returning the area back to its normal condition with no known side effects.
~ Osteopathy: Realignment of bony structures to ensure they are positioned correctly for pain-free optimal function and performance.
~ Neural Mobilization: Involves the conservative treatment of nerve decompression, a variety of various neural mobilizing techniques and patient education. This form of therapy offers a fresh understanding and management strategies for common syndromes such as plantar fasciitis, tennis elbow, nerve root disorders, carpal tunnel syndromes and spinal pain."
~ Ergonomics: The science of designing the surrounding work environment to fit the user in order to reduce the level of stress to the body, which left “unchecked”, can often result in the onset of both short and long-term Repetitive Strain Injuries.
~ Electrotherapy: Electrotherapy is used for muscle/tendon rehabilitation, reducing muscle spasms, preventing / slowing muscle atrophy, increase localized circulation, maintaining and/or increasing range-of-motion (ROM), management of both chronic / acute pain, post surgical muscle stimuli to reduce onset of muscle atrophy and increase blood-flow/circulation and to reduce onset of improper levels of scar-tissue development, and in some cases, for the delivery of specific medications through the skin membrane.
~ Thermotherapy: Treatment that involves the use of heat to reduce muscle spasm, scar-tissue restrictions / adhesions, increase the range-of-motion (ROM) and elasticity of muscles/tendons and for the overall relief of chronic pain and of course should not be used during the first 72-hours of any injury resulting in the swelling / inflammation of tissues.
~ Phototherapy: This form of therapy is used for a huge number of disorders, even Carpal Tunnel and Trigger Finger. It is believed that the exposure to daylight or specific wavelengths of light using lasers, light-emitting diodes, fluorescent lamps or bright, full-spectrum lights that will result in increased circulation providing healing nutrients to the injured area. Although this form of therapy is proven to treat a variety of disorders such as depression, seasonal anxiety disorders, etc., its use for treating Repetitive Strain Injuries had not bee proven.
~ Pre-Habilitation: Balancing the length and strength of muscles in the hand, wrist and forearm in order to help stabilize the joints and open the carpal tunnel wider, therefore providing more room for the flexor tendons and median nerve to function without the risk of impingement.
At What Point Should Treatment options be Considered?
Sooner is better than later so don’t let the injury harbor itself for months or years before you address it. The effective result of the treatment depends largely on early diagnosis and conservative treatment. If you have carpal tunnel syndrome seek treatment immediately, you have great chances of success in its treatment.
How Can this Condition be Prevented?
- Prevention takes place mainly in reducing the amount of gripping, holding and grasping of objects; any motion that involves excessive flexion of the fingers and wrist.
Ergonomic measures can help reduce its onset so make sure your work station is set up for you, not someone else and always use good posture.
Osteopathy to improve all the mechanics of the upper and avoid overloads tendons.
~ Flextend stretches and exercises for the fingers and wrist to help counteract all of the finger and wrist flexion that is being performed all day and in every activity that we do, both at work and recreation.
What’s the Short and Long-Term Prognosis?
The prognosis depends largely on when symptoms began and the actual cause of Carpal Tunnel Syndrome. If it is a muscle imbalance, you perform corrective exercises to help re-align the wrist joint and open the carpal tunnel more, if it is because you are obese, then the subject needs to lose weight, if it is due to pregnancy that involves fluid retention and weight gain, symptoms usually disappear after the baby is born. It also comes down to when treatment is sought and implemented. The longer a person waits to treat this condition, the more likely it is that damage to the median nerve may occur.
How is Carpal Tunnel Syndrome Diagnosed?
The diagnosis is made based on symptoms, reports of the patient (anamnesis), Differential Diagnosis, Manual Tests, Neurological Tests and Complementary tests (especially electromyography).
What Type of Healthcare Professional Should I See?
To search for a clinical diagnosis is important. The EMG is relied on heavily for diagnosis of Carpal Tunnel Syndrome but the manual tests such as Phalens, Reverse Phalens, Tinel’s Sign and the Durken test. All of these manual tests diagnose the condition and are much cheaper and less painful than the EMG.
For functional diagnosis you should seek a physical therapist, chiropractor or osteopath for evaluation. The prescription of physical therapy should be based on the cause of symptoms and the treatment protocol should include the appropriate corrective extension and finger abduction exercises. If you are prescribed flexion exercises, find a new therapist as it is excessive flexion (gripping, grasping) that causes the disorder in most cases and they are having you perform motions that contribute to its further development.
The key to treating carpal tunnel syndrome is to perform therapy that assists in opening the carpal tunnel and any associated structures that may hinder the passage of the median nerve within the carpal tunnel, improve body mechanics and posture and balancing the muscles in the hand and forearm.
Good luck with your health and be aware of the onset of symptoms and seek medical attention sooner rather than later!
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