Essay: THE EFFECTS OF LOWER EXTREMITY FUNCTION ON QUALITY OF LIFE IN LOCAL OLDER ADULTS

1. Introduction:
Aging, even in healthy older adults, is accompanied by a reduction in muscle mass and muscle strength (Gallagher et al., 1997). The gradual loss of muscle strength (below a certain threshold) results in functional impairment. This may result in the need for assistance in the performance of daily activities and an increased risk of falling and non-vertebral fractures (Goodpaster et al., 2006). Therefore, the preservation of muscle strength in older adults is of major importance. Lower extremity function is the use of lower limbs and is imperative for mobility, lower extremity function can be assessed using various practical tests with the patient and is most commonly evaluated via a lower extremity functional scale. A practical non-invasive and cost-effective solution to keeping good lower extremity function is through a basic exercise program (Marsh et al., 2009). Mobility is the key to leading a high quality of life with independence, thus a diminished lower extremity function may result in the patient having more dependence on others and will affect their quality of life (Shimada et al., 2013). Quality of life, even at an older age is of high significance, and can be defined as the everyday lifestyle and well-being of an individual. Quality of life can be measured in many ways, although, using a short form 36 is valid and reliable whilst using very limited resources (Costanza et al., 2008).
2. Defining lower extremity function:
Lower extremity function, which may also be referred to as LEF, is the function which consists of the movement of the lower limbs. The bones, which are the base of LEF include; the pelvis, femur, patella, tibia, fibula and talus. LEF may be defined by the movement of the lower extremities, especially the muscles and tendons. There is a conflict of interest as to what physiological function is included in the lower extremities. Some may include only the area from the tibiofemoral joint to the talocrural joint, while others may include the region between the coxal joint and the talocrural joint. For a more extensive definition of lower extremity function, the following information will be based on the region between the coxal joint and the talocrural joint. The main muscles which may be involved in LEF include, muscles of the hip region; gluteus maximus, gluteus medius, gluteus minimus, and the tensor fascia latae. Muscles of the upper leg, gracilis, rectus femoris, sartorius, vastus intermedius, vastus lateralis and vastus medialis. Muscles of lower leg, gastrocnemius, tibalis anterior, tibalis posterior and soleus.
Tendons have a crucial role in extremity function as they attach important muscles together which then attach to the designated bone. The main tendons which may be involved in LEF include; quadriceps tendon, patella tendon, and the achilles tendon, which has a high structural importance especially in regards to LEF as it connects the soleus and gastrocnemius to the calcaneus allowing them to function at their highest capacity.
The spine and nervous system are very important in regards to LEF as this is the key way to a majority of functions in the body. The spinal tract is the main transmitter for spinal signals, thus the signals sent from the brain to the legs or the legs to the brain are sent through here. Mostly, the brain will send the initial movement signals and the legs will send the receptor occurrence signals. The two main nerves include the femoral nerve and the sciatic nerve; these nerves then will branch off into multiple other nerves for LEF (Noble et al., 1998).
2.1 How Lower Extremity Function is measured
Muscle strength and endurance are usually measured by isometric, isotonic and isokinetic methods, plus simple testing. A measurement of muscle function should consider special aim, cost, and safety. In this project, we will study in the leg muscle function of older adults so we should choose the suitable methods, a survey and simple methods are suitable to older adults a link the details you have written in the draft (Conable and Rosner, 2011).
The Lower Extremity Functional Scale, abbreviated LEFS, was developed to quantatively assess a person’s ability and comfort level in performing his or her daily living activities. Twenty activities from a list are evaluated and scored from ‘0’, being extremely difficult or impossible to perform, to ‘4’, being able to perform the activity with no difficulty at all. The activities range from doing housework, hobbies, walking short distances, putting on items of clothing, lifting groceries, to more demanding tasks such as walking several blocks or climbing many sets of stairs. Of course the ability or inability in performing these activities relates entirely to the lower limbs being the limiting factor due to pain, or lack of movement or other symptoms.
As there are twenty activities each with a maximum score of four, the highest LEFS from the evaluation will be 80 points, which represents 100% function present. Any score less than this will give a corresponding lower functional assessment. The formula is a simple one, percent of function equals score/80 times 100%.
As the person undergoing evaluation and subsequent treatment can be retested, a metric is available to monitor progress, and to set patient goals for the future as improvement occurs.
Due to the somewhat subjective nature of the questions, and variability in the patient’s answers, a change of at least 9 points in the total score is required to denote a measureable change in the LEFS, and hence the patient’s true status of whether or not improvement is being made as treatment progresses, or may signal the need for changes in treatment strategy (Binkley et al., 1999). It should be noted here that the LEFS is intended for the adult population with diagnosis of lower extremity function symptoms.
Although the LEFS is classed as the gold standard when measuring lower extremity function, this is mainly used in rehabilitation and clinical settings. In some situations the testing personnel may prefer to run simple testing such as; walking speed, balance and rising from a chair without assistance. These are simple tests which can be run in most settings such as nursing homes, health care facilities, research facilities, universities, and even within a patient’s home. All testing should be conducted and supervised by suitable personnel.
A walking speed test is conducted by asking the patient to walk from one location to another at their regular pace and timing the duration that it takes. The distance is approximately 5m (or preferred distance by conductor) and return (Studenski et al., 2003).
There are various balance tests which could be performed by the patient; these tests are usually timed. Such tests can include tandem stance performed in four stages; stage one involves the patient standing with their feet side by side, stage two involves the patient placing the big phalange of one foot against the instep of the opposite foot, stage three involves the patient standing with the phalanges of one foot touching heel of the opposite foot, stage four involves the patient to stand on one foot (Hile et al., 2012).
The raise from a chair test is very simple; the patient is asked to sit in a chair at standard height, unaided, thus only using their lower extremity function to rise. If the patient is unable to do this, they are then asked to perform the task whilst using their arms as aids. In some testing, the patient is asked to repeat this task five consecutive times, which is then timed to provide results (Hardy et al., 2010).
It is imperative to assess the test and the patient for a risk assessment, fit patients would be less hazardous. For example, it would be less hazardous for an older adult patient to perform a tandem stance, stages 1 ‘ 3 and not undertake stage 4 unless aided or if they feel confident in doing so. Whereas there would be very little risk asking a healthy adolescence to perform all of the above testings without assistance. It is sometimes useful to also test the body mass index of the patient, also known as BMI; as this may be impeding on their results (Reid et al., 2008). The measure of BMI is straightforward; a calculation is based on the height and weight of the patient. The standard Australian formula for this is weight (kg)/height squared (m).
3. Defining quality of life:
The concept of using quality of life, QOL abbreviated, as a measurement across various health disciplines is still relatively new. Although, with the increasing constructive outcomes of using the evaluation of QOL additional medical personnel and facilities are starting to incorporate this concept for patient evaluations. QOL is a measurement of the psychological and physical function of an individual. Ultimately an evaluation of QOL may help medical practitioners, support staff researchers and even family members to have a better understanding of the patient’s situation and may also monitor their progress (Dimen??s et al., 1990). Thus, leading to a better route of treatment or even early prevention.
3.1 Why is Quality of Life measured?
There are various applications which can warrant the assessment of QOL in a person, depending on the situation. One of the most common examples is the use of a QOL assessment when a patient is in coma, although the patient is still alive the QOL is minimal. Other common assessment patient’s may include; mentally impaired, older adults and physically impaired (Felce and Perry, 1995).
Psychological assessment can be taken out in various ways. Although a QOL assessment may be taken at the clinician’s request, which may help with further treatment (Ferreira et al., 2009).
When older adults reach the point in their life where they can no longer be fully independent, a QOL assessment is carried out to evaluate the appropriate measures to take. The results are then categorised, which helps health care workers decide if the patient requires in-house assistance, and to what extent, or if it is recommended they go into a care facility (Gerritsen et al., 2007).
As medical conditions can impact a patient’s life in multiple ways and can have a dramatic effect on how they live their lives. Most medically impaired patients often have a QOL assessment in their medical consultations (Verdugo et al., 2014).
3.2 How Quality of Life is measured
There are many ways that quality of life can be assessed, including but not restricted to; surveys, for example the short form 36, observation and personal interview. Although various researchers or practitioners may prefer the use of a combination of assessments dependant on the situation, by doing this it increases the reliability of the results (Costanza et al., 2008).
The short form 36, commonly known as the SF-36 is commonly used for evaluating quality of life through acquiring patient information in questionnaire form. It has proven to be a reliable and valid source for acquisition of patient information. Although it was designed to be used in adolescence through to older adults, it is more-so frequently used in assessments for older adults. The SF-36 is a short questionnaire that contains multi-scale questions to cover physical and psychological health which are two crucial elements of a patient’s life, each with four subcategories. Physical health is measured through; physical function, physical role, body pain and assumptions on their own general health. Psychological health is measured through; social function, emotional role, vitality and assumptions on their own mental health (Ware and Sherbourne, 1992).
Unlike a lot of medical evaluations, the SF-36 does not require to be taken in a doctor’s consultation or laboratory, nor does it require any supervision. The SF-36 can be issued to the patient for them to fill in via mail, electronic or telephone correspondence. Unfortunately, a problem that may arise with a patient filling in their survey independently may cause discretions in the answers.
It is common that a clinician or researcher may carry out an interview with the patient as well as have them complete the SF-36 otherwise they may just want to evaluate the patient’s quality of life by only conducting an interview. The interview gives an insightful view of the patient’s perception of what their life is while also observing the patient to an extent. Depending on the patient, situation and interviewer, the questions may vary. A personal interview is a reliable source of gathering information, but is best used when used in combination with other measures (van der Poel et al., 2013).
Observation is an older style technique which is used in various clinical settings, especially in regards to the psychological field. Observation includes monitoring a patient’s behaviour and actions in different scenarios and everyday living. This can be done via personal observation or even through surveillance cameras. Observation of a patient can be carried out in their place of residency or in a clinical setting. Although observation is a very reliable source of gathering information, it unfortunately takes up a lot of time and resources, as it has to be carried out over a lengthy period of time to attain the best results. Observation is rarely used to measure quality of life, unless the patient is unable to attend an interview or fill out a questionnaire (Edelman et al., 2005).
4. Why is lower extremity function and quality of life important in older adults?
As the general population ages, it becomes important for older adults to have a sense of worth and psychological well-being by continuing to participate in society and to be able to perform leisure activities, work, household chores, and care of self. The measure of lower extremity function is just one of several satisfaction and performance metrics which define the overall health status of the older adult. To this end, a lower extremity activity profile (LEAP) can be defined as a comprehensive measure of a patient’s perception of difficulty, in which the LEFS scale is one part of the responsiveness to rehabilitation. Self-paced walking sessions administered pre- and post- operatively, for example, in knee replacement patients, as part of this activity profile, demonstrated a correlated improvement with the LEFS score (Finch and Kennedy, 1995).
The lower extremity function (LEF) of older adults is important to treat and monitor. Neglecting to do so in the proper manner can lead to the causing of negative physical, social and mental results. Patients of low LEF need independence; they tend to rely mostly on others to help them with everyday activities that were once so simple for them, but now prove to be a difficult reoccurring challenge to them. Such negative results of having to rely on people include the patient preferring to stay at home and secluding themselves, rather than going out and being social like they once were; which can then lead to depression, thus a lower quality of life. Another negative result would be a patient not receiving physical activity and therapy. Without physical activity and therapy, patients are prone to permanently losing mobility. However, asking the proper questions can aid the patient. Asking whether or not walking ten steps or a city block proves to be difficult to them (if it once was not a difficult task), can aid in the proper care and aid that they are in need of (Shimada et al., 2013).
5. Actions that can be taken to improve lower extremity function in older adults:
There are various actions which can be taken to improve lower extremity function in older adults. Due to older adults having varied circumstances which can be health related, financially related and even living facilities, which can impede on the patient being able to take the required actions. Thus, these circumstances must be taken into consideration before suggesting required action for the patient. Unfortunately, several of the actions that may be required to improve a patient’s LEF such as surgery and/or pharmaceuticals or supplements may be unaffordable for some. In this scenario, simple non-invasive exercises are advised. Some patients may need to incorporate more than one action to successfully increase their LEF; this will depend on their current health status.
Ideally the paramount way to maintain and improve LEF is by introducing an exercise program, however exercise programs can vary. The exercise programs will depend on the patient’s situation, medical condition, finances and accommodation. Older adults that may be accommodated in multiple living quarters such as a nursing home or retirement villages may have group sessions available to them, the exercise program will be based on the group as a whole which unfortunately means the individual’s needs may not be meet unless they seek a one on one consultation (Marsh et al., 2009).
Due to various older adults not being able to improve their LEF because of physical impairments which may be altered, it would be advised that the patient sees their medical practitioner about a possible joint replacement or similar. For patients who have recently received a joint replacement or similar or are considering the previously mentioned are advised to seek a rehabilitation specialist after their operation before commencing an exercise program.
Calcium and vitamin D are a significant part of bone formation and strength. As the body ages bones start to become brittle, which may cause fractures or other bone deformities impacting LEF. There are now various supplements which can be taken to increase the intake of calcium and vitamin D, in some cases it may not repair the full extent of damage if it has already occurred but may be used as a preventative measure (Bischoff-Ferrari et al., 2004).
6. Discussion:
As the population is getting older and costs in health care systems are increasing to look after an increasing number of people, it makes sense to encourage and put into practice physical fitness and rehabilitation programs for seniors to allow them to continue to do most of the activities they engaged in while they were younger.
Medical advances have prolonged lifespan, and healthy lifestyles have begun to offset disability due to heart disease and diabetes, thus shifting the focus from preventing disease to maintaining mobility.
In particular the importance of lower extremity function to allow walking, climbing, and simply getting around from room to room in a home permits seniors to maintain their independence, and hence their quality of life. This has obvious psychological benefits on mental health as well. A person will feel more sense of worth when they have the strength, endurance and flexibility to look after themselves, and to do the things they enjoy doing (Oh et al., 2014).
To this end, it is necessary then to have some quantitative measure of mobility function with the goal to determine if there is a decline in mobility and to do something about it early on. Mobility description can be subjective to the patient, as decline can be gradual enough that the person may think things are normal, since mobility might have been at a reduced level for many years. Without appropriate physical activity or therapy present, this would lead to permanent mobility loss (Ganesh et al., 2011). Therefore testing, together with treatment and physical activity, provide the best strategy for tracking mobility issues and providing the greatest opportunity to maintain mobility at the highest level possible for the longest time.
The traditional metrics used by health care professionals has been the SF-36 as a measure of health, and in particular, the LEFS lower extremity function score. As has been outlined, this latter test metric provides a score rating between 0 and 80 points of mobility function, with a change of 9 points indicating the minimum discernable change, positively or negatively, with respect to a prior test scoring.
When there is a loss of mobility in older adults, there are important psychological, physical and social results. Dependency on others for going out to eat or for entertainment and shopping can lead to avoidance and staying at home. This can lead to depression and feelings of lower self-esteem, and the resultant sedentary behaviour then leads to physical diseases and further deterioration of mobility. It is therefore important to address the issue as soon as possible. For most people, this should and can be addressed by a family physician (Quadri et al., 2005).
Since family physicians are so busy with heart and lung problems, screening for mobility, especially using a LEFS test gets a low priority. Although many researchers have found that two simple questions that can be asked by family physicians and social workers can be used to determine mobility issues in seniors. These are, one, ‘Do you have difficulty in climbing ten steps or walking a city block’?, and two, ‘Have you changed the way in which you climb ten steps or walk a city block’?. After causes due to heart disease or respiratory issues are ruled out, answers to these questions become, in essence, a stripped down version of the LEFS score (Rosso et al., 2011). The great advantage of these two simple questions is that they take very little time and can be asked by any doctor. The importance of being able to do this in a simple way cannot be overstated.
7. Conclusion:
To summarise this assessment, it comes as a quick realisation that older adults have a reduction in muscle mass due to the fact that they are growing older and their bones are becoming weaker, which in turn affects their lower extremity function, thus the function of the lower limbs resulting in limited mobility if the problem is not addressed. It is also evident that in order to be deemed as healthy, older adults need to have a high quality of life. As the SF-36 can measure eight domains of a patient’s life predominantly from physical and psychological based question, this is why it is one of the most commonly used methods for determining quality of life.
When researching this topic, it has been noted that there is an increase in medical advances that have helped with treatments of various diseases that have an increased risk of affecting older adults, for example medical conditions such as osteoarthritis, diabetes, osteoporosis and cardiovascular disease. With these advancements they are prolonging the lives of older adults, although, sometimes where medical field has advanced with technology, devices and pharmaceuticals, the straight-forward solutions such as an exercise programs have become over looked. All areas of the patient’s situation should be explored and taken into consideration before making any decision on which way to progress with their health care. Through age progression the body and mind can become weak and vulnerable; this is why it is impeccable to monitor ones health as it progresses, this can be done by frequent checks with a medical professional.
After thorough investigation on this topic it has been noted there are multiple studies that focus on older adults or LEF or QOL as individual parameters. While, there are very few studies using QOL, LEF and older adults as combined parameters. Conducting research projects on such topics can lead to increasing the QOL of older adults and possibly decreasing the rate of depending older adults on the health care system, and possibly extending life expectancy while having a high QOL.
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