Hand / Wrist Injuries
Work-related musculoskeletal disorders of the upper extremities, including the hands and wrists, are quite common and occur in nearly all types of work situations. Each year, direct Workers' Compensation costs due to these types of injuries are over $2 billion, plus an additional $90 million in indirect costs.
The highest rate of disorder was found in industry workers whose jobs required them to repeat the same type of forceful motion throughout their work shift, such as food processors, automobile and electronics assemblers, carpenters, office data entry workers, cashiers, and garment workers.
Disorders that affect the hand, wrist and fingers are often seen in people in these types of positions. The disorders may develop gradually, resulting from repeated actions and the twisting and bending of the hand, wrist, and arms, combines with force.
The most common work-related injury to the hands and wrist is carpal tunnel syndrome, which occurs when the median nerve becomes entrapped by irritated and swollen tendons in the wrist pressing on the nerve as it passes through the wrist. Workers whose jobs demand repetitive movement — not necessarily forceful or strenuous movements — of the wrist, hand and arm are most at risk for developing carpal tunnel syndrome.
Other types of injuries and conditions commonly found in the wrist, hand, and fingers include:
- Hand-Arm Vibration Syndrome
- Raynaud's Syndrome
- DeQuervain's Disease
- Trigger Finger
Some of the risk factors identified as being associated with the likelihood of developing work related injuries, such as a repetitive stress injury include:
- Repetitive, forceful, or prolonged exertions of the hands
- Rapid hand and wrist movement
- Frequent or heavy lifting, pushing, pulling, or carrying heavy objects
- Prolonged awkward postures
- Low temperatures
Additional factors influencing the likelihood of developing a work-related problem include intensity, frequency and duration of the exposure to conditions listed above. These risk factors are also coupled with individual capacity to deal with the conditions, personal factors such as age and physical condition, as well as sociocultural and psychosocial factors.
Carpal Tunnel Syndrome
What is Carpal Tunnel Syndrome?
To understand what carpal tunnel syndrome is, it is first important to understand the basic anatomy of the wrist. The carpal tunnel is named from the 8 carpal bones in the wrist that form a tunnel like structure. This tunnel is filled with tendons that control the movement of the fingers. It is also a pathway for the median nerve to reach the sensory cells in the hand. Repetitive flexing and extending of the wrist can cause the protective sheaths of each tendon to thicken. Carpal tunnel syndrome results from pressure on the median nerve caused by these swollen tendon sheaths.
What are the Symptoms?
Carpal tunnel syndrome may first occur as painful tingling in the hands at night. The pain may be significant enough to disturb sleep. There may also be a feeling of uselessness in the fingers that is sometimes described as a swollen feeling, even though there is no apparent swelling. Symptoms may progress to the point where the hands feel tingly and painful during the day. There may also be a decreased ability and power to squeeze. There may be an inability to distinguished between hot and cold touch, and the hands may appear clumsy in performing simple tasks such as tying shoes or picking up small objects.
What Causes Carpal Tunnel Syndrome?
Swelling of the tendons in the carpal tunnel cause carpal tunnel syndrome, but there are many things that can cause the tendons to swell. This swelling can result from repetitive and forceful movement of the wrist. NIOSH indicates that job tasks involving highly repetitive manual acts, or necessitating wrist bending or other stressful wrist postures, are connected to the incidents of carpal tunnel syndrome and related problems. Using vibrating tools may also be a contributing factor. The common factor in most job associated cases of carpal tunnel syndrome, however, is repetitive use of small hand tools.
NIOSH focuses on relieving awkward wrist positions and repetitive hand movements, and reducing vibration from hand tools, in its efforts to control carpal tunnel syndrome. This could involve the redesign of tools or tool handles so the wrist is in a more natural position during use and modifying layouts of work stations. Other ways of preventing carpal tunnel syndrome could include altering the way certain tasks are performed, frequent rest breaks, and rotating workers into different tasks.
Treatment of carpal tunnel syndrome may include anti-inflammatory drugs and hand splinting to reduce tendon swelling in the carpal tunnel. Steroid injections are very helpful. Ultimately, surgery may also be necessary to release the compression on the median nerve.