The Rising Risk of Upper Extremity Musculoskeletal Disorders (MSD) or Cumulative Tauma Disorders (CTD)
Note : This article is done based on references listed to share some basic points on Upper Extremity MSD/CTDs and encourage the undertaking of preventive measures. There are extensive amounts of references on this for more details, however to obtain proper diagnosis, prevention and recovery of MSD/CTDs, please seek medical attention.
Most of us suffer some form of CTD/MSD (single or combination of disorders) as a result of some predisposing factors that we are unaware of. It develops as we age and as we are exposed to more and more risk factors. ASEANS (including Malaysians) mostly experience long working hours and practice inappropriate ergonomics and this is why cases of CTD/MSD are increasing.
1. What is CTD / MSD
Definition : disorders of the nerves, muscles, tendons & bones that are caused, precipitated or aggravated by repeated exertions or movements of the body. These are occupational-related and also caused/aggravated by living factors. Two main categories :
i. cervicobrachial disorders – myofascial pain disorders, thoracic outlet syndrome (TOC), cervical spondylosis
ii. nerve compression syndromes – eg. carpal tunnel syndrome is the most common compression neuropathy in the upper extremity– caused by repetitive wrist flexion and extension with the fingers flexed, affecting the wrist & hand
Single or a combination of disorders may exist in patients and one CTD/MSDs may affect the other. Patients who understand the pathogenesis of their condition, understand the rehabilitation and prevention issues.
1.1 Cause and Factors
Ergonomics (the study of work & workplace) blends human characteristics with the living & working environment, revealing that sedentary nature of work, inappropriate work station, mechanical stress, nutritional inadequacies, metabolic & endocrine dysfunctions, chronic infection, insufficient physical exercise causes or enhanced risk of CTD/MSD.
This means how we perform work – work posture at work station/computer, sleeping posture, carrying things, using tools – heavy/vibration, long-term sitting posture without break & exercise, driving posture & car ergonomics. Job stress (anxiety & tension) & the repetitive nature of many tasks in modern industry are leading to CTDs not to mention job frustration. Physical factors mainly force, repetition, vibration, posture/ergonomics, cold temperature heightens risk for most disorders along with the predisposing factors that are likely to cause or aggravate signs/symptoms. Being overweight or obese is a serious risk factor that not only increases your risk for all health problems but also CTD / MSD. Women are at higher risk in most cases (mainly those with underlying factors) – congenital reasons, hormonal problems (including thyroid problems), bone formation/shape, vasculature etc.
1.2 Treatment and Rehabilitation – based on specific injury/disorder & whichever appropriate based on patient’s condition
These are performed with medical advise upon proper diagnosis of the condition. It’s recommended by experts to seek second opinion if necessary. Usually some or all of these are required :-
Surgery in some situations and/or Injection / Anti-inflammatory Drugs Physical therapy – stretching programme / therapeutic exercises (yoga, swimming, etc), heat/ice, ultrasound, electrical stimulation, massage Occupational therapy – appropriate work station and work posture (ergonomics) to reduce of stress loads on the neck & shoulders, posture strengthening, sufficient break and exercise, use of personal protective equipment/support tools (PPE) eg splints and back support/brace etc.
1.3 Motivation for Rehabilitation/Recovery
Motivation is required for the recovery (i.e. rehabilitation) of function. Desire to get well often influences the ability to get well. Motivation for recovery may not have direct effect on how the patient react to this disorder. It may effect his attitude and lifestyle – And lifestyle is what rehabilitation is all about.Most patients are motivated to get well and most of them wish to be rehabilitated once they understand what rehabilitation means. They are many who don’t want to go back to work or who are deterred by factors that impede the rehabilitation efforts by the healthcare. However, if the patient plays a passive role, if he expects recovery will be granted to him, if he is disinterested or uninformed, then surely all attempts to rehabilitate him will fail.
2.0 Carpal Tunnel Syndrome (CTS) & Thoracic Outlet Syndrome (TOC)
Hands have a special significance in that their function is so complex & they are related to earning a living. The proper function of hands are required to enable us to touch, feel, hug, caress, lift, grip, hold things, eat, bath and carry out other dialy routine activities. Your ability to feel or touch your family or loved ones, and to perform daily activities comfortably is affected when you have CTD/MSDs. In most CTD/MSDs, hand is the upper extremity affected most.
CTS affects the wrist and hands and is the most common compression neuropathy in the upper extremity – caused by repetitive wrist flexion and extension with the fingers flexed.
Sign & symptoms of CTS – strain/stiffness, pain, numbness/loss of sensation, tingling sensation, heaviness, temperature changes. Predisposing factors for carpal tunnel syndrome (CTS) are inflammatory, trauma, neoplasias, deposition of biosynthetic product, abnormal vasculature, and other system conditions. Women are at higher risk as the size of their carpal are much smaller than men. Physical factors that heighten risk : force (pressing keyboard hard, or hard keyboards), repetition (continuous typing and clicking), vibration (car and other vibrating tools, or equipment with insufficient vibration control), posture/ergonomics (improper seating/seat design, workstation & seat height in relative to each other etc, angle/postion of computer in relation to the individual’s posture), cold temperature. Cold temperature harms the dexterity of fingers/hand, can cause numbness
Risky postures that should be avoided :-
Long-term sitting, standing or repetitious shoulder & scapular motion Improper posture of the back & neck / improper seating affect the position of the wrist and the hand, thus causing strain and repetitive trauma injuries (RTI) to the wrist, hands, back, neck, shoulder. This can lead to nerve compression syndrome and TOC. The forward head, rounded shoulder posture is a predisposing factor in the development of Thoracic Outlet Syndrome (TOC) which usually co-exists with CTS in some individuals. Sitting with legs crossed under the other and leaning on one elbow while using computer, as this eliminates ergonomic support & enhance the likehood of MSD/CTD. Hanging the hand on the top of a car steering wheel for a prolonged time.
3.0 Measures for Prevention and Rehabilitation of CTD / MSD
Refer to DOSH guidelines on seating and using VDU and other references at the end of this article mainly ‘carpal tunnel syndrome exercises’ and’ physical activity for everyone’ for prevention of CTD/MSD
Practice good posture and working habits. Rest in between work – exercise between work eg after every 30 min of using the computer take break for at least 20 min . Exercise regularly 
erform 3-5 hrs a week of moderate-intensity aerobic exercise OR 2-3 hrs a week of vigorous-intensity aerobic exercise And muscle-strenghthening exercise – twice a week. Prevent from being overweight and obese.
4.0 Conclusion
As a conclusion, I intend to share my advice to the community and the public/private sector employers.
- I pledge to the public and private sector as well as every individual to take necessary measures to prevent and control MSD/CTD to be able to fulfill our rising personal, family, social and health needs.
- Create posts for psychologist/occupational therapist at public/private workplace similar to those in the developed countries to provide advice/care on occupational health risks thus enabling healthy working habits, stress management and healthy lifestyle.
The right knowledge, attitude and practice is the key to prevention and control of health problems. So don’t wait, start now!
References :
DOSH Malaysia Guidelines for Seating At Work, 2002
DOSH Malaysia Guidelines for Working with VDUs, 2003
Occupational Hand & Upper Extremity Injuries & Diseases, Edition by Mordon L Kasdan, M.D., FACS.
Carpal Tunnel Syndrome Factsheet : National Institute of Neurological Disorders and Stroke (NINDS) www.ninds.nih.gov/disorders/carpal_tunnel/detail_carpal_tunnel.htm