Musculoskeletal disorders (MSDs) are injuries or pain in the human musculoskeletal system, including the joints, ligaments, muscles, nerves, tendons, and structures that support limbs, neck and back. MSDs can arise from a sudden exertion (e.g., lifting a heavy object), or they can arise from making the same motions repeatedly repetitive strain, or from repeated exposure to force, vibration, or awkward posture. Injuries and pain in the musculoskeletal system caused by acute traumatic events like a car accident or fall are not considered musculoskeletal disorders. MSDs can affect many different parts of the body including upper and lower back, neck, shoulders and extremities (arms, legs, feet, and hands). Examples of MSDs include carpal tunnel syndrome, epicondylitis, tendinitis, back pain, tension neck syndrome, and hand-arm vibration syndrome.
|Carpal tunnel syndrome is a common musculoskeletal disorder, and is often treated with a splint.|
MSDs can arise from the interaction of physical factors with ergonomic, psychological, social, and occupational factors.
MSDs are caused by biomechanical load which is the force that must be applied to do tasks, the duration of the force applied, and the frequency with which tasks are performed. Activities involving heavy loads can result in acute injury, but most occupation-related MSDs are from motions that are repetitive, or from maintaining a static position. Even activities that do not require a lot of force can result in muscle damage if the activity is repeated often enough at short intervals. MSD risk factors involve doing tasks with heavy force, repetition, or maintaining a nonneutral posture. Of particular concern is the combination of heavy load with repetition. Although poor posture is often blamed for lower back pain, a systematic review of the literature failed to find a consistent connection.
People vary in their tendency to get MSDs. Gender is a factor, with women having a higher incidence of MSDs than men. Obesity is also a factor, with overweight individuals having a higher risk of some MSDs, specifically of the lower back.
There is a growing consensus that psychosocial factors are another cause of some MSDs. Some theories for this causal relationship found by many researchers include increased muscle tension, increased blood and fluid pressure, reduction of growth functions, pain sensitivity reduction, pupil dilation, body remaining at heightened state of sensitivity. Although there is no consensus at this time, some of the workplace stressors found to be associated with MSDs in the workplace include high job demands, low social support, and overall job strain. Researchers have consistently identified causal relationships between job dissatisfaction and MSDs. For example, improving job satisfaction can reduce 17-69 per cent of work-related back disorders and improving job control can reduce 37-84 per cent of work-related wrist disorders.
Because workers maintain the same posture over long work days and often several years, even natural postures like standing can lead to MSDs like low back pain. Postures which are less natural, such as twisting of or tension in the upper body, are typically contributors to the development of MSDs due to the unnatural biomechanical load of these postures. There is evidence that posture contributes to MSDs of the neck, shoulder, and back. Repeated motion is another risk factor for MSDs of occupational origin because workers can perform the same movements repeatedly over long periods of time (e.g. typing leading to carpal tunnel syndrome), which can wear on the joints and muscles involved in the motion in question. Workers doing repetitive motions at a high pace of work with little recovery time and workers with little to no control over the timing of motions (e.g. workers on assembly lines) are also prone to MSDs due to the motion of their work. Force needed to perform actions on the job can also be associated with higher MSD risk in workers, because movements which require more force can fatigue muscles quicker which can lead to injury and/or pain. Additionally, exposure to vibration (experienced by truck drivers or construction workers, for example) and extreme hot or cold temperatures can affect a worker's ability to judge force and strength, which can lead to development of MSDs. Vibration exposure is also associated with hand-arm vibration syndrome, which has symptoms of lack of blood circulation to the fingers, nerve compression, tingling, and/or numbness.
Assessment of MSDs is based on self-reports of symptoms and pain as well as physical examination by a doctor. Doctors rely on medical history, recreational and occupational hazards, intensity of pain, a physical exam to locate the source of the pain, and sometimes lab tests, X-rays, or an MRI Doctors look for specific criteria to diagnose each different musculoskeletal disorder, based on location, type, and intensity of pain, as well as what kind of restricted or painful movement a patient is experiencing. A popular measure of MSDs is the Nordic Questionnaire that has a picture of the body with various areas labeled and asks the individual to indicate in which areas they have experienced pain, and in which areas has the pain interfered with normal activity.
Prevention of MSDs relies upon identification of risk factors, either by self-report, observation on the job, or measurement of posture which could lead to MSDs. Once risk factors have been determined, there are several intervention methods which could be used to prevent the development of MSDs. The target of MSD prevention efforts is often the workplace in order to identify incidence rates of both disorders and exposure to unsafe conditions.
Groups who are at particular risk can be identified, and modifications to the physical and psychosocial environment can be made. Approaches to prevention in workplace settings include matching the person's physical abilities to the tasks, increasing the person's capabilities, changing how tasks are performed, or changing the tasks. Employers can also utilize engineering controls and administrative controls to prevent injury happening on the job. Implementation of engineering controls is the process of designing or redesigning the workplace to account for strengths, weaknesses, and needs of the working population- examples would be workstation layout changes to be more efficient or reducing bending over, or moving necessary tools within shorter reach of the worker's station. Employers may also utilize administrative controls like reducing number of hours in a certain position, limiting overtime, or including more breaks during shifts in order to reduce amount of time at risk for each worker.
Encouraging the use of proper ergonomics not only includes matching the physical ability of the worker with the correct job, but it deals with designing equipment that is correct for the task. Limiting heavy lifting, training, and reporting early signs of injury are examples that can prevent MSD. Employers can provide support for employees in order to prevent MSD in the workplace by involving the employees in planning, assessing, and developing standards of procedures that will support proper ergonomics and prevent injury.
One focus of ergonomic principles is maintaining neutral postures, which are postures in which muscles are at their normal length and able to generate the most force, while reducing stress and possible injury to muscles, tendons, nerves, and bones- therefore, in the workplace or in everyday life, it is ideal for muscles and joints to maintain neutral positions. Additionally, to prevent hand, wrist, and finger injuries, understanding when to use pinch grips (best for fine motor control and precise movements with low force) and power grips (best for high-force movements done repeatedly) is important for employees and general tasks outside the workplace. The choice of tools should match that of the proper grip and be conducive to neutral postures, which is important for employers to consider when purchasing equipment. In order to reduce injuries to the low back and spine, it is recommended to reduce weight and frequency of lifting cycles as well as decreasing the distance between the body and the load to reduce the torque force on the back for workers and individuals doing repeated lifting to avoid fatigue failure of the spine. The shape of objects being lifted should also be considered, especially by employers, because objects which are easier to grip, lift, and access present less stress on the spine and back muscles than objects which are awkwardly shaped and difficult to access.
The National Institute of Occupational Safety and Health (NIOSH) has published ergonomic recommendations for several industries, including construction, mining, agriculture, healthcare, and retail, among others.
MSDs are an increasing healthcare issue globally, being the second leading cause of disability. For example, in the U.S. there were more than 16 million strains and sprains treated in 2004, and the total cost for treating MSDs is estimated to be more than $125 billion per year. In 2006 approximately 14.3% of the Canadian population was living with a disability, with nearly half due to MSDs. Neck pain is one of the most common complaints, with about one fifth of adults worldwide reporting pain annually.
Most workplace MSD episodes involve multiple parts of the body. MSDs are the most frequent health complaint by European, United States and Asian Pacific workers. and the third leading reason for disability and early retirement in the U.S. The incidence rate for MSDs among the working population in 2014 was 31.9 newly diagnosed MSDs per 10,000 full-time workers. In 2014, the median days away from work due to MSDs was 13, and there were 10.4 cases per 10,000 full-time workers in which an MSD caused a worker to be away from work for 31 or more days. MSDs are widespread in many occupations, including those with heavy biomechanical load like construction and factory work, and those with lighter loads like office work. The transportation and warehousing industries have the highest incidence rate of musculoskeletal disorders, with an incidence rate of 89.9 cases per 10,000 full-time workers. Healthcare, manufacturing, agriculture, wholesale trade, retail, and recreation industries all have incidence rates above 35 per 10,000 full-time workers. For example, a national survey of U.S. nurses found that 38% reported an MSD in the prior year, mainly lower back injury. The neck and back are the most common sites of MSDs in workers, followed by the upper limbs and lower limbs. The Bureau of Labor Statistics reports that 31.8 new cases of MSDs per 10,000 full-time workers per year are due to overexertion, bodily reaction, or repetitive motions.
Following Maurice de Montmollin (philosopher and psychologist at the Sorbonne), the French distinguished generally two major trends in ergonomics:
Ergonomics focuses on the activity, which emphasizes understanding the work situation as a whole, the demand analysis and framework intervention and the distinction between prescribed work and real work. This school is mainly present in the Francophone countries, Brazil and another form in Scandinavia.
The ergonomics of the human factors, focusing on research results General (on the postures, rhythms, moods of work ...) and definition of standards. It is dominant in the United States and Japan.Computer-induced medical problems
Computer-induced health problems can be an umbrella term for the various problems a computer user can develop from prolonged and incorrect computer use. A computer user may experience many physical health problems from using computers extensively over a prolonged period of time in an inefficient manner. The computer user may have poor etiquette when using peripherals, for example incorrect posture. Reportedly, excessive use of electronic screen media can have ill effects on mental health related to mood, cognition, and behavior, even to the point of hallucination.Electronic pipettes
An electronic pipette is a particular air-displacement pipette where the manual movement of the piston is replaced by a compact motor powered by a battery and driven by an integrated microcontroller. The plunger present on the mechanical pipette, and that is typically pressed with the thumb of the user, is replaced by a button which triggers the movement of the electric motor.Epicondylitis
Epicondylitis is a type of musculoskeletal disorder that refers to an inflammation of an epicondyle. It is caused by repetitive motion. In athletes, it is linked to poor technique. Nonsurgical treatment is effective in approximately 95% of cases.Types include:
Lateral epicondylitis, also known as tennis elbow.
Medial epicondylitis, also known as golfer's elbow (Also thrower's elbow).Ergonomic hazard
Ergonomic hazards are physical conditions that may pose risk of injury to the musculoskeletal system, such as the muscles or ligaments of the lower back, tendons or nerves of the hands/wrists, or bones surrounding the knees, resulting in a musculoskeletal disorder (MSD). Ergonomic hazards include awkward postures, static postures, large forces, repetitive motion, or short intervals between activity. The risk of MSD is often magnified when multiple factors are present or when whole-body or hand/arm vibration, poor lighting, or poorly designed tools, equipment, or workstations produce additional negative interactions with the worker/user. Ergonomic hazards occur in both occupational and non-occupational settings such as in workshops, building sites, offices, home, school, or public spaces and facilities.German Shepherd
The German Shepherd (German: Deutscher Schäferhund, German pronunciation: [ˈʃɛːfɐˌhʊnt]) is a breed of medium to large-sized working dog that originated in Germany. In the English language, the breed's officially recognized name is German Shepherd Dog (sometimes abbreviated as GSD). The breed was officially known as the Alsatian in Britain until 1977 when its name was changed back to German Shepherd. Despite its primitive, wolf-like appearance the German Shepherd is a relatively modern breed of dog, with their origin dating to 1899. As part of the Herding Group, German Shepherds are working dogs developed originally for herding sheep. Since that time however, because of their strength, intelligence, trainability, and obedience, German Shepherds around the world are often the preferred breed for many types of work, including disability assistance, search-and-rescue, police and military roles, and acting. The German Shepherd is the second-most registered breed by the American Kennel Club and seventh-most registered breed by The Kennel Club in the United Kingdom.Human factors and ergonomics
Human factors and ergonomics (commonly referred to as human factors) is the application of psychological and physiological principles to the (engineering and) design of products, processes, and systems. The goal of human factors is to reduce human error, increase productivity, and enhance safety and comfort with a specific focus on the interaction between the human and the thing of interest. It is not simply changes or amendments to the work environment but encompasses theory, methods, data and principles all applied in the field of ergonomics.The field is a combination of numerous disciplines, such as psychology, sociology, engineering, biomechanics, industrial design, physiology, anthropometry, interaction design, visual design, user experience, and user interface design. In research, human factors employs the scientific method to study human behaviour so that the resultant data may be applied to the four primary goals. In essence, it is the study of designing equipment, devices and processes that fit the human body and its cognitive abilities. The two terms "human factors" and "ergonomics" are essentially synonymous.The International Ergonomics Association defines ergonomics or human factors as follows:
Ergonomics (or human factors) is the scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data and methods to design to optimize human well-being and overall system performance.
Human factors is employed to fulfill the goals of occupational health and safety and productivity. It is relevant in the design of such things as safe furniture and easy-to-use interfaces to machines and equipment.
Proper ergonomic design is necessary to prevent repetitive strain injuries and other musculoskeletal disorders, which can develop over time and can lead to long-term disability.
Human factors and ergonomics is concerned with the "fit" between the user, equipment, and environment or "fitting a job to a person". It accounts for the user's capabilities and limitations in seeking to ensure that tasks, functions, information, and the environment suit that user.
To assess the fit between a person and the used technology, human factors specialists or ergonomists consider the job (activity) being done and the demands on the user; the equipment used (its size, shape, and how appropriate it is for the task), and the information used (how it is presented, accessed, and changed). Ergonomics draws on many disciplines in its study of humans and their environments, including anthropometry, biomechanics, mechanical engineering, industrial engineering, industrial design, information design, kinesiology, physiology, cognitive psychology, industrial and organizational psychology, and space psychology.John Holmes Dingle
John Holmes Dingle (24 November 1908–15 September 1973) was an American physician and medical professor.Kyphoscoliosis
Kyphoscoliosis describes an abnormal curvature of the spine in both a coronal and sagittal plane. It is a combination of kyphosis and scoliosis. This musculoskeletal disorder often leads to other issues in patients, such as under-ventilation of lungs, pulmonary hypertension, difficulty in performing day-to-day activities, psychological issues emanating from anxiety about acceptance among peers, especially in young patients. It can also be seen in syringomyelia, Friedreich's ataxia, spina bifida, Kyphoscoliotic Ehlers-Danlos Syndrome (kEDS), and Duchenne muscular dystrophy due to asymmetric weakening of the paraspinal muscles.Long Island serial killer
The Long Island serial killer (also referred to as LISK, the Gilgo Beach Killer or the Craigslist Ripper) is an unidentified suspected serial killer who is believed to have murdered 10 to 16 people over a period of nearly 20 years, mostly women associated with prostitution, and left their bodies in areas on the South Shore of Long Island, New York.
The victims were found along the Ocean Parkway, near the remote beach towns of Gilgo and Oak Beach in Suffolk County, and the area of Jones Beach State Park in Nassau County. The remains of four victims were found in December 2010, while six more sets of remains were found in March and April 2011. Police believe the latest sets of remains predate the four bodies found in December 2010.On May 9, 2011, authorities surmised that two of the newest sets of remains might be the work of a second killer. On November 29, 2011, the police stated their belief that one person is responsible for all 10 deaths. They also had concluded that the case of Shannan Gilbert, an escort who went missing before the first set of bodies were found, was not related. "It is clear that the area in and around Gilgo Beach has been used to discard human remains for some period of time," said Suffolk County District Attorney Thomas Spota.Musculoskeletal injury
Musculoskeletal injury (MI, not to be confused with myocardial infarction) refers to damage of muscular or skeletal systems, which is usually due to a strenuous activity. In one study, roughly 25% of approximately 6300 adults received a musculoskeletal injury of some sort within 12 months—of which 83% were activity-related. MI spans into a large variety of medical specialties including orthopedic surgery (with diseases such as arthritis requiring surgery), sports medicine, emergency medicine (acute presentations of joint and muscular pain) and rheumatology (in rheumatological diseases that affect joints such as rheumatoid arthritis). In many cases, during the healing period after a musculoskeletal injury, a period in which the healing area will be completely immobile, a cast-induced muscle atrophy can occur. Routine sessions of physiotherapy after the cast is removed can help return strength in limp muscles or tendons. Alternately, there exist different methods of electrical stimulation of the immobile muscles which can be induced by a device placed underneath a cast, helping prevent atrophiesNeurofibromatosis type I
Neurofibromatosis type I (NF-1) is a complex multi-system human disorder caused by the mutation of a gene on chromosome 17 that is responsible for production of a protein called neurofibromin which is needed for normal function in many human cell types. NF-1 causes tumors along the nervous system which can grow anywhere on the body. NF-1 is one of the most common genetic disorders and is not limited to any person's race or sex. NF-1 is an autosomal dominant disorder which means that mutation or deletion of one copy (or allele) of the NF-1 gene is sufficient for the development of NF-1, although presentation varies widely. As of 2015, there are at least 100,000 people in the U.S. and about 15,000 people in the UK who have been diagnosed with NF. Common symptoms of NF-1 include brownish-red spots in the colored part of the eye called Lisch nodules, benign skin tumors called neurofibromas, and larger benign tumors of nerves called plexiform neurofibromas, scoliosis (curvature of the spine), learning disabilities, vision disorders, mental disabilities, multiple café au lait spots and epilepsy. NF-1 affected individuals also have a much higher rate of cancer and cardiovascular disease than the population in general.
NF-1 is a developmental syndrome caused by germline mutations in neurofibromin, a gene that is involved in the RAS pathway (RASopathy). Due to its rarity and to the fact that genetic diagnosis has been used only in recent years, in the past NF-1 was in some cases confused with Legius syndrome, another syndrome with vaguely similar symptoms, including cafe-au-lait spots.NF-1 is an age specific disease; most signs of NF-1 are visible after birth (during infancy), but many symptoms of NF-1 occur as the person ages and has hormonal changes. NF-1 was formerly known as von Recklinghausen disease, after the researcher (Friedrich Daniel von Recklinghausen) who first documented the disorder.The severity of NF-1 varies widely, and little is known about what causes a person to have a more severe or less severe case. Even within the same family (as there is a 50% chance that a parent will pass their condition to their offspring), levels of severity can vary enormously. However, 60% of people with NF-1 have mild cases, with few symptoms that have very little effect in their day-to-day lives. 20% of NF-1 patients have moderate cases, with several symptoms that have little more than cosmetic effects. The other 20% have severe cases with several symptoms that affect the person's quality of life. Even in this last group, symptoms are rarely life-threatening.Occupational safety and health
Occupational safety and health (OSH), also commonly referred to as occupational health and safety (OHS), occupational health, or workplace health and safety (WHS), is a multidisciplinary field concerned with the safety, health, and welfare of people at work. These terms also refer to the goals of this field, so their use in the sense of this article was originally an abbreviation of occupational safety and health program/department etc.
The goals of occupational safety and health programs include to foster a safe and healthy work environment. OSH may also protect co-workers, family members, employers, customers, and many others who might be affected by the workplace environment. In the United States, the term occupational health and safety is referred to as occupational health and occupational and non-occupational safety and includes safety for activities outside of work.In common-law jurisdictions, employers have a common law duty to take reasonable care of the safety of their employees. Statute law may in addition impose other general duties, introduce specific duties, and create government bodies with powers to regulate workplace safety issues: details of this vary from jurisdiction to jurisdiction.Repetitive strain injury
A repetitive strain injury (RSI), is a category of injuries "to the musculoskeletal and nervous systems that may be caused by repetitive tasks, forceful exertions, vibrations, mechanical compression, or sustained or awkward positions". Other common names include repetitive stress disorders, cumulative trauma disorders (CTDs), and overuse syndrome.Tarsal tunnel syndrome
Tarsal tunnel syndrome (TTS), also known as posterior tibial neuralgia, is a compression neuropathy and painful foot condition in which the tibial nerve is compressed as it travels through the tarsal tunnel. This tunnel is found along the inner leg behind the medial malleolus (bump on the inside of the ankle). The posterior tibial artery, tibial nerve, and tendons of the tibialis posterior, flexor digitorum longus, and flexor hallucis longus muscles travel in a bundle through the tarsal tunnel. Inside the tunnel, the nerve splits into three segments. One nerve (calcaneal) continues to the heel, the other two (medial and lateral plantar nerves) continue on to the bottom of the foot. The tarsal tunnel is delineated by bone on the inside and the flexor retinaculum on the outside.
Patients with TTS typically complain of numbness in the foot radiating to the big toe and the first three toes, pain, burning, electrical sensations, and tingling over the base of the foot and the heel. Depending on the area of entrapment, other areas can be affected. If the entrapment is high, the entire foot can be affected as varying branches of the tibial nerve can become involved. Ankle pain is also present in patients who have high level entrapments. Inflammation or swelling can occur within this tunnel for a number of reasons. The flexor retinaculum has a limited ability to stretch, so increased pressure will eventually cause compression on the nerve within the tunnel. As pressure increases on the nerves, the blood flow decreases. Nerves respond with altered sensations like tingling and numbness. Fluid collects in the foot when standing and walking and this makes the condition worse. As small muscles lose their nerve supply they can create a cramping feeling.Xiphoid process
The xiphoid process , or xiphisternum or metasternum, is a small cartilaginous process (extension) of the lower (inferior) part of the sternum, which is usually ossified in the adult human. It may also be referred to as the ensiform process. Both the Greek derived xiphoid and its Latin equivalent ensiform mean 'swordlike'.
Diseases of joints (M00–M19, 711–719)
(one joint /