Knee pain is one of the most common work-related musculoskeletal disorders in Singapore. According to a study done by the Osteoarthritis Research Society International, 25.7% of Singaporeans above the age of 50 years old are diagnosed with knee osteoarthritis. This has shown a significant increase from the mid-1990s to 2000s. The number of patients diagnosed with knee osteoarthritis has increased more than 10% (from 14.3% to 25.7%) in just 5 years. A local cross-sectional study on knee pain in an outpatient clinic found that 63% of them are manual workers and 25% are non-manual workers. Another cohort study has shown that people working in the food and beverage industry have the highest age-standardized cumulative salary-adjusted incidence rate of symptomatic knee osteoarthritis. Cross-sectional studies done on construction workers have also shown a high prevalence of knee pain at 54%. The knee is the most commonly injured joint in any individual. Compared to other joints, the extreme range of movement, load bearing, and functional alignment up to the ankle makes the knee especially vulnerable to damage. It is often subjected to high forces. These forces are repetitive in high frequency and the duration is long. Knee pain can be caused by many reasons. Some common examples are osteoarthritis, ligament sprain or tears, and meniscus injuries. Symptoms can range from pain, swelling, and stiffness to total disability. High levels of pain commonly occur at night or during changes in the weather. The pain and disability can cause restrictions in an individual’s ability to walk and climb stairs, and thereby limit their activities that can lead to an unhealthy and sedentary lifestyle. In severe conditions of total disability, surgeries such as knee arthroplasty might be needed.
Overview of Knee Pain in Singaporean Workers
Knee pain in a worker affects his productivity and work. There would be an increased amount of taking MC or medical leave, which would shorten the time of production for that person. This injury also forces the injured worker to change his or her job to a lower-paying or less skilled one. This, in turn, results in a loss of income for a family and a consequence of an increase in the percentage of households underneath the poverty line. It also affects the mental well-being of that person. A study has shown that workers feel less satisfied with their current job after suffering from a work-related injury.
Singapore is a densely populated city, with more than 5 million in population. The traffic is massive at most times, causing people to travel long distances to get to their workplace. Wearing high heels to be more presentable in the office environment can also pose a risk for knee pain. All these contribute to knee pain and injury, which amounts to 149 per 1000 people in 2007, according to statistics from the Ministry of Manpower. This rate is 36% higher than the average in the world. The disparity and rate of work-related knee injuries weigh heavily on profitable employment and production aimed by the companies in knee pain Singapore. So, it is considered a major issue to address in order to prevent loss of productivity and job amputation for such injured workers.
Importance of Occupational Therapy for Knee Pain Management
Occupational therapists (OTs) are skilled at directly and indirectly addressing the occupational performance needs of clients. As the strongest evidence supporting the effectiveness of OT is through addressing environmental and occupation-based needs, OT intervention is highly relevant to the working populations. The aim of this paper is to explore the current strategies employed by OTs to manage knee pain in Singaporean workers. Due to the multifaceted nature of knee pain and limited published literature specific to the Singaporean working population, this paper will draw on a range of literature related to the pathophysiology of knee pain and evidence of OT intervention with relevance to client-centered practice. This will provide an understanding of the issues involved in managing knee pain for OTs and indicate directions for future research that will support evidence-based practice. OT intervention has been reported to be effective in treating knee pain and its outcomes for various populations. A study reported a randomized controlled trial with relatively strong methodology that supports the effectiveness of weight-bearing exercise on pain and functional performance for people with medial tibiofemoral knee OA, which are common symptoms of knee pain. The exercises were delivered by a physiotherapist or occupational therapist and focused on improving the individual’s ability to spend prolonged periods of time on their feet, thus suitable for application to a working population. This is further supported by a study which concluded that the more closely interventions match patient preferences and provide a sense of mastery, the better the results achieved in the management of chronic diseases. This is a practice-based concept for occupational therapists and is often what makes OT intervention effective, however patient preferences and specific issues related to pain are varied and an understanding of the most effective strategies is required. OTs have an ability to apply therapeutic exercises and provide education on self-management for knee pain, however a key strategy which complements these interventions and may be more effective is addressing issues related to work. This may involve advice or modification of a specific task, work simplification, joint protection, or changes to the work environment. The effectiveness of such strategies is relative to individual patients and OTs require a strong understanding of their clients’ occupations and the specific issues they wish to address. Measures of implementing such strategies and their direct effect to manage knee pain require further research specific to the nature of knee pain in today’s working populations. This paper will also explore the implications of knee pain on work for Singaporean workers, thus providing a more specific understanding of the occupational performance issues involved.
Strategies for Preventing Knee Pain
An ergonomic modification is a change to the work environment, equipment or work process which seeks to reduce discomfort or strain in an employee. In relation to knee pain or injuries, ergonomic workplace modifications should seek to reduce the amount of load placed on the knee during work activities. For call center workers, this might involve a headset to reduce the need for standing, or sit-to-stand workstations for office workers. For more manual type work, it might involve the use of equipment to reduce the load on the knee when lifting or carrying heavy items. An individual with knee pain or injuries may benefit from reducing the amount of time spent on their feet. Employers should strive to find alternative work activities for these employees which do not exacerbate their knee condition, while not disadvantaging the employee.
Employees and employers can employ various strategies to prevent knee pain and injuries at the workplace. Some of these are similar to the treatment techniques for knee pain and injury, and there is evidence to support their effectiveness. While it will be impossible to prevent all injuries from occurring, it is realistic to expect a reduction in the number and severity of knee injuries with successful implementation of these prevention strategies. We can reduce the prevalence of knee pain and injuries in the workplace, and potentially slow the progression of osteoarthritis in the knee, a condition which often follows people with knee pain and injuries.
Ergonomic Workplace Modifications
If the individual has a physically demanding job, it may be difficult to offload the work tasks from the knee. An occupational therapist would work towards changing the way the job is done, such as reducing the amount of weight lifted and carried. This may involve providing assistance from other coworkers, changing the equipment used to perform the task, or changing the process in how the task is completed. For example, an employee working in construction as a bricklayer was finding it difficult to lift and carry heavy packs of bricks up ladders and over uneven ground. This was resulting in increased pain and swelling in his knee, as well as frequent episodes of giving way in the knee. A strategy to offload this task was to have another worker carry the bricks and only go up the ladders when the bricks were in position to be laid. An alternative process was to use lighter bricks and stack them on a trolley to be pushed along level ground to the work site. By implementing these strategies, the load on the individual’s knee was greatly reduced.
In the workplace, many tasks require the individual to be on their feet constantly. In an industrial setting, this may involve prolonged periods of standing or walking, and in office settings, it may involve sitting for extended periods. Due to the workload, the diminished capacity positions may go unnoticed for a period of time and result in an overuse injury. Ergonomic modifications to the workplace can help individuals with knee pain to take stress off the knee and allow healing, as well as prevent further injury. An ergonomic assessment by an occupational therapist would involve consideration of the demands of the job tasks in relation to the health problem, observation of the individual in the work setting, and recommendations on how to change the work environment or the way the job is done.
Proper Body Mechanics and Posture
When sitting: – Sit all the way back in the seat. Use a back support if your chair is too deep. – Distribute body weight equally on both hips. – Keep your knees at hip level or slightly higher. – Keep feet flat on the floor.
When standing: – Keep your head up and shoulders straight and squared. – Pull your stomach in. – Keep your feet pointing straight ahead. – Maintain the hollow in your low back. – Make sure you are putting equal weight on both feet.
Proper body mechanics and posture are especially important in preventing knee pain. Adopting and maintaining good posture will help distribute the load carried by the knee joint and reduce unnecessary stress placed on the muscles and ligaments. Proper body mechanics, which means moving your body in a way to prevent injury to any part of the body, will help reduce the risk of sudden twists or movements that can cause knee injuries.
Regular Exercise and Stretching
Aquatic exercises are particularly beneficial for patients with knee pain. The buoyancy of water reduces the compressive forces acting on the knee, and the viscosity of water provides resistance for strength training. It is often easier and less painful for patients to perform exercises in the water, so they are more likely to comply with the exercise regimen. This is important because the long-term adherence to exercise is an important factor in its effect on knee pain. Static cycling and cycling on a fixed base bike are also effective ways of maintaining quadriceps muscle strength at a pain-free level of the knee. High-resistance and low-repetition cycling focusing on the down-stroke of the pedal has been shown to increase quadriceps muscle strength without causing aggravation to the patellofemoral joint. This is important for individuals with patellofemoral pain syndrome who may aggravate their symptoms with higher resistance cycling up hills or on the road.
Poor muscle strength and flexibility contribute to the development of knee pain. The muscles of the thigh act as dynamic stabilizers of the knee joint during movement and ambulation. Weakness of the quadriceps muscle is significantly linked to the incidence of osteoarthritis in the knee. The hamstring muscles also play an important role in the stabilization of the knee joint, and tightness in this muscle group may also be related to increased knee pain. Regular exercises to maintain strength and flexibility of the quadriceps and hamstrings, as well as the muscles of the lower leg, are important in preventing knee pain. These exercises should be performed in a pain-free range of motion and should not increase knee pain during or after the exercise.
Occupational Therapy Interventions for Knee Pain
Occupational therapists aim to reduce knee pain by minimizing the stress placed on the knee during daily activities. Therapists achieve this by educating the patient on the use of pain management techniques, assistive devices, and activity modification. Studies report that the best pain management technique is exercise. This improves the strength and coordination of the knee, reducing the daily functional impact of knee OA. Exercise also has a systemic effect, improving the patient’s overall well-being. Other pain management techniques include weight management and the use of thermal modalities. Weight management has been found to significantly reduce the risk of developing symptomatic knee OA in older obese persons. A loss of 11 pounds can cut the risk of OA in the women studied by half. Thermal modalities work to control and relieve pain. A cold pack can reduce pain and muscle spasm. Heat helps to relax tensed muscles and improve the blood flow to the knee. Although drug therapies and orthotics are not within the scope of occupational therapy, therapists should be aware of these management techniques and keep the patient informed.
Pain Management Techniques
Transcutaneous Electrical Nerve Stimulation (TENS) has been recognized as an effective method for pain relief. TENS relieves pain by sending low voltage electrical impulses to selected nerve pathways in the area of the pain. This suppresses the pain signals sent to the brain from the spinal cord, thus altering the pain sensation. The client will feel a tingling sensation under the electrodes and may experience an increase in pain a few hours later or the following day. This is known as rebound pain, and it should be monitored by the occupational therapist to determine the effectiveness of TENS. The duration and frequency of TENS should be agreed upon to prevent dependency and promote client involvement in their own treatment. This should always be done under the guidance of a therapist and should not be performed over the heart, on the head and neck, internally, on areas of skin irritation, or over a malignancy.
Occupational therapists use a variety of pain management techniques for clients experiencing knee pain. These interventions are based on the client’s presentation and individual factors. One of the methods of managing pain is to use thermal therapy. This can be achieved through superficial heat or cold. Heat can be administered through hot packs or warm whirlpool, while cold can be administered through ice massage or cold packs. Contrary to popular belief, the choice of either heat or cold therapy is not dependent on the nature of the injury. A general rule of thumb is to use heat for chronic conditions to help ease stiffness, and cold for acute trauma to relieve pain or inflammation. Heat and cold are safe and cost-effective agents that can be taught to the client for self-administration.
Assistive Devices and Equipment
A particularly important device for these clients would be a height-adjustable chair or a chair stool. This is due to the nature of their jobs in which they are required to alternate between sitting and standing tasks (e.g. a factory worker moving between workbench and machinery or an assembly line worker). A chair stool would enable a worker to continue tasks that would normally be done standing and can be a good motivational aid by preventing the client from avoiding standing tasks which may worsen their knee pain.
Common assistive devices include: a cane to reduce the stress on the affected lower limb, special cushions on chairs to increase comfort and reduce pain, knee braces to provide stability and reduce pain in unstable knee joints, and custom-made insoles to correct any misalignments in the feet or relieve pain in the feet or legs. Any use of these devices will also be used in conjunction with education on how to enhance their effectiveness to promote safety and ensure that the client is using the most suitable device. For example, teaching a client how to correctly size a cane and which hand to hold it in accordance with a lower limb injury or providing education on various types of knee braces and their indications.
Assistive devices are tools that aid a person in completing a task, whereas assistive equipment is the context in which the device is used to enable function. Both devices and equipment will be used in this case to enable the clients to continue working with knee pain in a safe and comfortable environment. This will help to prevent the pain from worsening and to reduce the risk of further injury. It is of particular importance in this case to enable the clients to continue working due to the fact that work is the main contributor to the onset of knee pain in this population, and many days off work have already been taken post knee injury in attempts to rehabilitate. This has resulted in decreased income and a negative financial impact for the clients.
Activity Modification and Adaptation
Sitting causes twice the pressure on the back of the knee cap compared to standing. Kneeling causes even higher pressure on the knee cap. People with painful knees usually prefer not to kneel and may actively avoid kneeling as it causes pain. If kneeling is necessary for work or social activities, then it is useful to find an alternative kneeling position. Padding the knee with a foam pad or cushion reduces the pressure on the knee cap compared to direct kneeling on the ground. A half-kneeling position, where one foot is on the ground and the other knee is supported by the other foot, can also reduce the load on the knee compared to full kneeling. This is the usual preference for older people and people with knee problems. Consider using these alternative positions for gardening, floor-level domestic tasks, or during sports activities that involve kneeling.
If you are unable to avoid a painful activity, there are strategies to reduce the stress on your knee joint. These strategies can be employed to produce longer-term benefits for your knee problem. They can reduce the risk of aggravating or accelerating your condition and may also prevent the development of associated problems in other parts of the body. It is useful to compare the loads on the knee during different activities to help in understanding how the activities can be modified to reduce the stress on the knee joint.
Rehabilitation and Recovery for Knee Pain
Exercise therapy should aim to alleviate pain, restore normal patellofemoral joint and muscle function, improve strength and coordination of the leg muscles, and increase the flexibility of the hamstrings and the iliotibial band. Eight weeks of exercise-based rehabilitation can improve both short-term and long-term recovery for patellofemoral pain. These improvements will directly correlate with a reduction in the amount of time off work and reduced future episodes of knee pain.
The initial management strategy of knee pain is non-operative and conservative in nature. The initial therapeutic exercise approach is directed at addressing the impairments and functional limitations identified in the examination. Exercise is the most effective way to rehabilitate a knee that has patellofemoral pain. Recent reviews have supported the use of exercise therapy in the management of patellofemoral pain. Exercise therapy has been shown to provide greater improvements in pain and function than non-exercise intervention. There is also good evidence that exercise therapy is more beneficial than arthroscopic lavage or placebo surgery for knee osteoarthritis. This literature supports the use of exercise-based rehabilitation for knee pain of various pathologies. The next section provides a guideline for how to prescribe therapeutic exercise for knee pain.
Physical Therapy Exercises
Range of motion often refers to the amount of movement that a person can move their knee in various locations. With a thesis patient, it will be hard to move due to the pain, and also higher degrees of inflammation will make the joint become stiff. When the joint becomes stiff, the muscles become weak and the nerves become painful. The main aim is to relax the muscle contracture and relieve the pain. The early ROM exercise needs to be easy so that it will not stress the patient and can be tolerated by the patient. The exercise can be done by letting the patient lay supine without the pillow. Then let gravity straighten the knee. This position needs to be held for 5 minutes. Then the patients can slowly bend their knee until comfortable. This position, the patient needs to hold for 10 seconds. These two exercises need to be done 2-3 times a day. The next exercise is quadriceps setting. This isometric exercise will maintain muscle strength. In simple terms, isometric exercise means muscle contraction without the movement of the joint. This exercise is very easy and can be done anywhere and anytime. The patient needs to start sitting with knee support. Then he or she needs to press the affected knee downward to the floor while straightening the knee and hold that position for 10 seconds. This exercise needs to be done 10 times every session and do the session 2-3 times a day. The next exercise is the ankle pump. This exercise will help maintain the blood circulation surrounding the knee. When this exercise is done, the blood will act like a natural repair to repair the injury. The ankle pump exercise is moving the ankle up and down, 15 times every 5-10 minutes.
Patients with the thesis disease will be feeling terrible that they need to stay away from movement and work for a long run. They need our support so that they still have faith that they will recover soon and their disease can be cured. The Physical Therapy only has one goal, and that is to help the patients get back to normal condition as soon as possible. An exercise-based approach is the best method and strongly recommended to treat knee pain patients, and it is also safe and less expensive. There are a few exercises that can be done to try to relieve the pain.
Gradual Return to Work Program
Involving the employer in managing and facilitating a functional progression back to work is essential. It provides early identification of any workplace factors that may hinder recovery and an opportunity to modify these. It also ensures good communication between all parties involved, which is the key to a successful return to work. Scheduling a meeting to discuss the employer’s expectations and the worker’s restrictions and/or limitations will help in developing a plan. The discussion should also include planning for and monitoring the worker’s progress. This may involve a graduated increase in hours and/or duties and a specified timeframe for a review of the plan. This is the usual procedure for a worker undergoing a functional progression as a result of a work injury, however notable it should be highlighted that this is also effective for workers rehabilitating from a knee injury. Step-down programs that involve a physically demanding job can also be simulated in a therapy environment. For example, a carpenter may have a program to simulate work tasks to match the demands of his job, often starting with simpler tasks such as data entry to gradually increase the demands before returning to his original job. This process may require 3-4 weeks with up to 3 sessions per week. Any simulation programs must be monitored and reviewed constantly to ensure the knee symptoms do not worsen. A tracking tool to monitor progress such as the example shown in Table 1 is useful to ensure everyone is on the same page.
4.3 Psychosocial Support and Coping Strategies
Patients with higher perceived social support from medical professionals, significant others, and physical therapists present with better adherence and clinical outcomes. Hence, it is important for the patient to know that healthcare professionals have a genuine concern for their recovery. This sets the foundation for the therapeutic relationship, which in itself is a vehicle for treatment and has been shown to be a positive predictor in clinical outcomes in a variety of different conditions. A qualitative study on the interaction between patients and physical therapists showed 5 components to the therapeutic relationship: the patient as an individual, positive regard, an explanation focused on patient understanding, agreement on goals and tasks in therapy, and development of an interpersonal bond. It is important for the PT to remember the patient’s pre-injury roles in various social situations and to consider those as goals throughout the rehabilitation process.
Many occupational knee injuries or those which occurred due to wear and tear over time do not require surgery. In such cases, psychosocial factors play a more important role in the recovery process. One of the main issues is the change of self-identity and loss of the ‘worker’ role and financial stability. This can result in further mental health issues such as depression and anxiety. Hence, it is important to maintain the injured worker’s self-esteem and morale. This can be done through emotional and instrumental social support from family, friends, employer, and colleagues.