Healed by the Light
04/08/18COLD LASERS IN PAIN MANAGEMENT
04/08/18Signs & Symptoms
Definition: Carpal tunnel syndrome is related to the compression of the median nerve of the wrist. This nerve is responsible for the sensitivity of the thumb and the 2 or 3 neighboring fingers. It is also the motor nerve that controls the muscles at the base of the thumb.
The carpal tunnel, formed by the transverse carpal ligament and the carpal bones. The "carpal tunnel" is in fact a tunnel formed behind by the 8 small bones of the wrist, which have the shape of a gutter; this gutter is closed in front by a very thick ligament, the "anterior annular carpal ligament".
Symptoms: It is initially expressed by tingling in the fingers, then by night pain in the hands. Subsequently, burning pain and paresthesias on the ventral surface of the hand and fingers with radiating pain in the forearm gradually appear. In addition, a decrease in the sensation of distribution of the median nerve and an atrophy of the muscles at the base of the thumb may occur.
Symptoms may range from minor to severe dysfunction. Moderate cases resolve with avoidance of factors. Once a pregnant woman gives birth, for example, the wrist swelling disappears and the symptoms of carpal tunnel syndrome diminish.
Often, the main complaint revolves around episodes of paresthesia and numbness of the hand in the evening. Symptoms may appear during activities such as driving or typing on a keyboard. The onset is insidious: patients describe tingling in the fingertips. Symptoms are often relieved by shaking or elevating the hand. Nocturnal numbness of the hand is present in 70% of cases; and pain with paresthesias is present in 40% of cases.
In addition to pain and paresthesia, there is a subjective sensation of invalidity in the fingers, clumsiness during activities requiring precision such as buttoning a blouse, writing, sewing, unscrewing a cork, turning keys or picking up small objects. Even light objects such as a coffee cup or clothing can be difficult to handle. Some patients may feel as if their hands are "swollen".
In severe cases, hand and wrist pain is described as burning, stabbing pains that may spread to the shoulder, neck, chest. Sensory loss radiates along the median nerve distribution accompanied by muscle weakness, slow nerve conduction through the carpal tunnel is characteristic.
Symptoms gradually intensify and severe cases may progress to muscle atrophy with sensory loss. The symptoms can make the patient disabled and prohibit certain simple tasks making daily life difficult. A long ignored disease can cause irrevocable damage.
It is a condition that predominates in women over fifty. The pain is typically located on the volar side of the first three fingers of the hand, but can affect the whole hand and even radiate to the front side of the forearm.
More than real pain, it is more often a question of tingling, of extremely annoying tingling. The nocturnal recrudescence of these pains is usual, waking up the patient at night, often at the same time. Certain gestures calm the pain, by shaking the hand or by letting it hang outside the bed.
Vasomotor disorders are frequent, with hypersudation or edema of the hand. Initially nocturnal, these painful phenomena persist during the day, thus handicapping the patient in everyday household activities. Bilateral forms are frequent, with a clear predominance of one side.
The examination may be normal, thus limiting the symptomatology to subjective phenomena; this is stage I. It can show the existence of objective sensory disturbances in the territory of the median, and particularly at the level of the pulp of the first three fingers; this is stage II. It can reveal the presence of motor disorders at the level of the opponent of the thumb, with readily amyotrophy of the thenar eminence; this is stage III.
How is it diagnosed?
Often, people who suffer from carpal tunnel syndrome seek medical attention. Part of the assessment for carpal tunnel syndrome includes a search for occupational risk factors. The assessment begins with a job analysis and requires a detailed description of all activities in a typical work day. The frequency, intensity, duration and regularity of each operation performed during the work are also taken into account. The diagnosis of carpal tunnel syndrome is confirmed by tests designed to identify damage to the median nerve.
Questionnaires
Which hand is most involved in work activities?
Is an accidental event the cause of the pain?
Questions about previous work activities: Work performed, duration in months, and factors involving the hand or upper limb?
Questions about hand/wrist activities: Frequency of movement and force required to flex, extend, or rotate wrists, apply pressure with fingers or palm, handle small objects, handle, pull, or push heavy objects, use vibrating or impact tools, other activities to be specified?
Questions about co-factors that increase musculoskeletal loading: Wearing work gloves, exposure to cold, and upper extremity abducted or flexed more than 60 degrees?
Questions about the organizational factors of the job: In the course of their work, does the person have to feed a machine tool at a regular rate; does the person work under time or production constraints; does the person have to pay a lot of attention; does the person perceive their work as monotonous; can they change their work pace; do they rotate to other jobs; are there other organizational factors that may have contributed to the problem? If so, what are they?
Questions about sports or domestic activities involving the hand or the wrist: Type of activities, number of hours per week and others?
Physical examination
Carpal tunnel syndrome should be diagnosed and treated promptly as it can be potentially irreversible if the median nerve is compressed for too long. A physical examination of the hands, arms, shoulders and neck can help determine if your symptoms are related to your daily activities or to an underlying disorder.
It is important before proceeding with the physical examination to take a good medical history and to document the various professional, sports, recreational or domestic activities that could have contributed to the appearance of this syndrome.
The symptoms are mainly sensory (paresthesias) affecting the first three fingers of the hand, but may also have a motor component. They are due to the compression of the median nerve at the carpal tunnel. Painful radiations affecting either the other fingers of the hand or the forearm may also accompany these symptoms. The patient may express the following symptoms:
- nocturnal paresthesias in the hand (numbness and tingling that usually disappears when the hand is shaken - Flick's sign)
- paresthesias occurring during activities involving the wrist and hand
- discomfort in the hand, wrist and forearm
- muscle weakness and clumsiness of the hand
The physical examination must include in addition to the wrist and the hand, the entire upper limb and the cervical region. The examination must include: observation and palpation, provocation tests, evaluation of tenderness and muscle strength. It may be supplemented by electrodiagnostic studies.
Observation and palpation
The upper limb: observe if there are deformities, signs of old fractures, tumors, osteoarthritis; examine the antalgic regions; compare the two members
Orthopedic and neurological tests
Your doctor of chiropractic may also do other specific orthopedic tests to try to replicate the symptoms of carpal tunnel syndrome. One of these tests is called Tinel's sign and involves tapping your finger lightly on the back side of your wrist to see if there is tingling or pain in your hand. Phalen's test is also useful. It involves bringing your wrist into maximum flexion and holding it there for some time. This maneuver can produce tingling or numbness in the fingers.
Challenge tests
There are two carpal tunnel provocation tests:
- the test for increasing intracarpal pressure (Phalen's test). Sign of Phalen - The patient places his hands back to back and bends his wrists for one minute. A tingling sensation in the fingers suggests a median nerve injury.
- the median nerve percussion test (Tinel's test). Sign of Tinel - The doctor lightly taps the median nerve at the wrist. A tingling sensation in one or more fingers suggests a median nerve injury.
Sensitivity tests
There are two categories of tests to assess sensitivity:
innervation density tests like;
- the discrimination test between two static points
- the needle prick test
and the tests of perception of the sensory threshold like;
- the Semmes-Weinstein monofilament test
- tests that evaluate the vibratory threshold.
Assessment of muscle strength
The following structures should be tested for strength:
- the hand as a whole
- the bidigitale (thumb-index) clamp
- the abductor brevis of the thumb
- the opposite of the thumb.
Radiology
Laboratory tests and X-rays may reveal the presence of diabetes, arthritis, fractures, and other causes that could cause pain in the wrists and hands.
X-rays usually show nothing abnormal unless there is an obvious change in bone structure due to old fractures or arthritic lesions. Blood tests are also normal, except in the presence of conditions that may be contributing to the problem, such as rheumatoid arthritis.
X-rays of the wrists and hands are not always necessary. It allows to detect a narrowing of the canal of post-traumatic osseous origin. On the other hand, X-rays of the cervical spine are sometimes requested to eliminate a compression upstream or associated with the wrist compression.
Electrodiagnosis
This test is usually performed in a specialized department. Sometimes electrodiagnostic tests, such as nerve conduction velocity, are used to help confirm the diagnosis. Electrodes are placed on the forearm and an electrical current is passed through them to determine how fast and to what extent the median nerve is transmitting nerve messages to the muscles, thus determining if the nerve has been damaged. Carpal tunnel syndrome will slow down the speed of these nerve impulses and point your doctor or chiropractor to this diagnosis. So, nerve conduction tests or an electromyography (EMG) help determine if the nerves and muscles in your arm and hand show the typical signs of carpal tunnel syndrome.
Electrodiagnostic studies are an essential adjunct to the examination. It confirms the presence of the syndrome and estimates the severity of sensory and motor damage.
Magnetic Resonance Imaging (MRI)
In the more complex forms, magnetic resonance imaging can be used in the event, in particular, of failure of a surgical intervention or atypical forms (forms on exertion or extrinsic compression). Magnetic resonance imaging (MRI) of the wrist finds indications in recurrences: It makes it possible to assess the appearance of the anterior annular ligament and the contents of the carpal tunnel.
Ultrasonography/ultrasound
Ultrasound can confirm tendon inflammation with a thickened tendon and a fluid layer encompassing the tendons.
Conclusion
The biological workup shows nothing special. A systematic search for diabetes, a frequent favouring factor, is necessary.
Differential diagnosis
When faced with sensory disorders of the hand that may resemble carpal tunnel syndrome, it is important to make a differential diagnosis.
Central nervous system disorders
- Transient cerebral ischemia
- Multiple sclerosis
Peripheral nervous system disorders
- cervical radiculopathy (C6, C7)
- thoracic outlet syndrome
- Raynaud's syndrome
- compression of the median nerve, for example by the pronator teres muscle in the forearm
- systemic diseases such as diabetes and alcoholism
- taking medication
- exposure to toxic substances such as lead, solvents, pesticides and plastics
Carpal tunnel syndrome is often difficult to diagnose. 25% patients with nerve disorders pose a problem of differential diagnosis (false positives) with other diseases such as Raynaud's phenomenon as well.
It is difficult to determine whether the primary cause is due to an occupational or medical problem, as many conditions, including obesity and other diseases, can contribute.
A positive diagnosis is suggested by the occupational history, confirmed by the presentation of appropriate symptoms, by physical examinations (Phalen's test, Tinel's sign) and confirmed by electromyogram or median nerve conduction defects, as well as by X-ray of the cervical spine.
The most common are C6-C7 nerve root disorders, thoracic spinal crossing syndrome and peripheral neuropathies; pronator syndrome (compression of the median nerve at the elbow) or anterior interosseous nerve syndrome.
The causes
Carpal tunnel syndrome is related either to a retraction of the anterior ligament (container), or more often to an increase in volume of the flexor tendons (synovitis or inflammation of the content).
This results in compression and progressive loss of conduction of the median nerve. In an ultimate stage, the chronic compression of the nerve can end up laminating it and destroying it completely, in an irreversible way.
There are multiple factors that favor the appearance of carpal tunnel syndrome: repeated trauma to the palmar surface of the wrist, bone anomalies protruding into the canal, hormonal changes in women, kidney dialysis, obesity (especially in young patients), etc. There also seems to be a genetic predisposition.
This syndrome is most often found in women.
In women, the cause is usually hormonal, which is why this syndrome is more common in pregnant women and women nearing menopause.
In humans, the cause is almost exclusively mechanical, typically, the worker frequently using a jackhammer or other vibrating tools.
The forms of carpal tunnel syndrome of occupational origin are numerous in Quebec. Injuries attributable to repetitive work or poor workstation design, such as carpal tunnel syndrome, have been recognized by the CSST, the courts and the Canadian Centre for Occupational Health and Safety.
It is more and more frequently observed in people working on a non-ergonomic computer workstation (keyboard, mouse, poorly adapted seat position...). In this case, it is sufficient to review the configuration of the workstation to remedy it.
Other causes are more rare: tenosynovitis, compression by the flexor muscles during rheumatoid arthritis, infectious causes, algodystrophies, amyloid deposits (during hemodialysis).
The syndrome is more common in diabetes, hypothyroidism, myeloma, sarcoidosis…
A significant number of carpal tunnel syndromes have no identified cause (idiopathic).
Some people have a narrower carpal tunnel than others, which makes median nerve entrapment more likely. In other cases, carpal tunnel syndrome can develop due to an injury to the wrist that causes the tunnel to become inflamed and the blood vessels supplying the median nerve to become compressed, an overactive pituitary gland, hypothyroidism, diabetes, inflammatory arthritis, mechanical problems in the wrist, poor work ergonomics, repeated use of vibrating hand tools, and fluid retention during pregnancy or menopause.
In addition, this syndrome may be associated with repetitive occupational trauma (CUMULATIVE TRAUMATIC DISORDERS); wrist trauma; AMYLOID NEUROPATHY; RHUMATOID ARTHRITIS; ACROMEGALIA; other diseases.
Its regression
When the carpal tunnel syndrome is related to a general pathology (e.g. diabetes), the treatment of this pathology is imperative in first intention and the regression of the symptoms will be of medium to long term.
Similarly, the syndrome occurring during pregnancy usually regresses after delivery without any intervention.
In other cases :
In stage I, where the symptoms are purely sensitive and subjective in nature, it is possible to be satisfied with immobilizing the hand and wrist with a brace, at least at night, with prescription of painkillers and/or anti-inflammatory drugs, but their action is most often very transient and in many cases will require more permanent therapeutic means, such as soft laser therapy or surgery in some cases.
If, however, you have recourse to local infiltrations of corticosteroids (cortisone, prednisone), be aware that in many cases, the symptom relief effect will only be temporary, temporarily reducing the inflammation of the nerve which is tight in the canal, that it is not recommended to inject more than three times during the yearReference 4 and that there are inherent risks with these injections, including the possibility of developing type II diabetes, even after a single injectionReference 123 .
In stages II and III, with objective sensory and motor disorders, the indication of a laser therapy The use of soft tissue is strongly recommended and the indication for surgery may be mandatory if no other treatment has succeeded in resolving the problem.
The results of surgery are on the whole excellent, provided that the nerve has not been damaged by prolonged compression and that the differential diagnosis has been made rigorously; ruling out other probable causes, including cervical radiculopathy (C6, C7) which may mimic symptoms of carpal tunnel syndrome. However, surgery has many disadvantages including loss of work due to convalescence, possible permanent scarring and the risks inherent in any surgery including infections.Reference 5 and side effects of anestheticsReference 6to name a few.
Before considering surgery, it would be beneficial to attempt to address this debilitating condition with soft laser therapy. It has no side effects and in many cases (84% of effectiveness)Reference 7, to completely relieve the symptoms of the carpal tunnel within more or less six weeks, and this, without having to be absent from work and suffer from the loss of income that accompanies it.