Varsha Gandhi, Debbie Brown and Esther Williamson
Low back pain is common amongst older adults (usually considered to be people over 65 years of age). Nearly one third of older adults reported bothersome back pain in the last month, more often than hip or knee pain.1 Older people, as compared to younger people, report less benign or mild back pain as they get older and experience more back pain that is severe or disabling, interfering with life and restricting social and physical function.2 Back pain in older adults is strongly associated with immobility, disability, frailty and falls.3,4
The population is ageing. In 2010, there were 10 million people in the UK over 65 years old. It has been predicted that there will be 5½ million more elderly people in 20 years’ time with the number expected to almost double to around 19 million by 2050. As the population ages the burden on the healthcare system is expected to grow. Back pain may appear to be of low priority compared to other heath conditions. However, it is probable that effective treatment of back pain in later life could yield substantial benefit in relieving or preventing loss of mobility, disability, and potentially frailty and falls. Despite this, the management of back pain is often ignored or not prioritized by both patients and clinicians. When examining the back pain literature, most clinical trials exclude older people,5 and it may not be appropriate to extrapolate findings from younger populations to older patients. In old age, there are well-recognized pathologies (such as neurogenic claudication arising from lumbar spinal stenosis). Some interventions used in younger people appear substantially less effective in older people, e.g., Cognitive Behavioural Approaches.6 There are unique challenges to managing back pain in older people. The impact of co-morbidities has to be considered, as do medication interactions and side effects. Older patients also commonly have the additional challenges of physical changes, including reduced muscle strength and reduced fitness, which are exacerbated by pain and inactivity. In addition, beliefs held by patients, the general public, and clinicians about pain and aging are barriers to accessing or engaging with potentially helpful treatments such as exercise or increasing physical activity. For example, there is a common view amongst patients that pain is simply a normal part of ageing and nothing can be done. This attitude may prevent patients from seeking appropriate care. Similarly, there is evidence that clinicians are less likely to recommend pain clinics for older people, expect poorer outcomes for older people and may be inclined not to encourage physical activity.
In order to manage back pain effectively in older people, clinicians need to have an understanding of these issues. This chapter will provide an overview of important concepts related to ageing including frailty, sarcopenia, falls and the impact of comorbidities, and their relationships with lower back pain (LBP). We will also examine the current evidence base available to guide patient management and provide recommendations for the rehabilitation of older adults with back pain.
CONDITIONS ASSOCIATED WITH BACK PAIN IN OLDER ADULTS
There are several conditions associated with back pain in older adults, such as osteoarthritis (OA) and spinal stenosis. OA is a disease of articular cartilage loss, bony hypertrophy and synovial thickening that can affect the facet joints of the lumbar spine.7 Degenerative changes are the result of an imbalance between the synthesis and degradation of the matrix of articular cartilage. It is commonly associated with disc degeneration and loss of disc height, which results in redistribution of load within the spine. These changes are common in older adults, but there is a poor correlation with symptoms and some authors suggest these changes should be viewed as normal ageing.7 These degenerative changes may be more important when features such as bony spurs start to encroach on neural or vascular structures as occurs in spinal stenosis.
Lumbar spinal stenosis is an anatomical or functional reduction in the anterior-posterior and transverse diameters of the spinal canal. A bulging intervertebral disc, posteriorly, thickened ligamentum flavum and hypertrophied facet joints can combine to produce a reduction in the cross-sectional area of the spinal canal.8 Symptoms are thought to arise when the stenosis or narrowing of the canal is sufficient to cause compression of the contents of the canal, particularly the neural and vascular structures. This results in vascular compromise to the vessels supplying the cauda equina as well as pressure on the nerve root complex. There is an important dynamic component to spinal stenosis. In a normal spine, the cross-sectional area of the spinal canal increases when moving from extension to flexion and during axial distraction. With spinal stenosis, there is a 12-30% reduction in the cross-sectional area of the spinal canal when moving from flexion to extension,8 which may account for the typical presentation of patients. The site of compression may be central, lateral or a combination of the two. Symptoms arising from spinal stenosis are also referred to as neurogenic claudication.9 A common presentation is pain or other discomfort that radiates from the back into one or both lower extremities, which is provoked or worsened by standing and walking (activities involving lumbar extension) and is relieved by sitting or bending (lumbar flexion). In addition to pain, leg symptoms can include fatigue, heaviness, weakness and/or paraesthesia, and patients can also suffer from nocturnal cramps and neurogenic bladder symptoms.9
Up to 47% of individuals aged between 60-69 years will have radiological evidence of spinal canal narrowing. However, the correlation between radiographic findings and clinical findings is poor.10 Symptomatic spinal stenosis or neurogenic claudication is less common but is estimated to affect between 10 and 14% of adults over 70 years of age.10 Spinal stenosis is the most common reason for spinal surgery in those over 65.
THE IMPACT OF BACK PAIN IN OLDER ADULTS
Back pain is a common reason for visiting a General Practitioner (GP). Approximately 8% of patients over 50 years of age that are registered with a primary care practice consult their GP with back pain each year. It is estimated that 70% of people over 70 with back pain reported visiting their GP at least once over the previous year and 60% of those aged 60-70 with back pain also consulted their GP. Amongst a cohort of over 5000 older adults consulting their GP with back pain, as many as 75% reported on-going back pain 12 months after their initial consultation.11
Pain can considerably impact on the ability of older adults to carry out their everyday tasks. Mobility problems, poor grip strength, slower gait and difficulty performing activities of daily living have all been found to be more common in older people with pain (including back pain) than those without pain.1-4 Older people with back pain have significantly lower health-related quality of life than the general population.
Low back pain is a potential threat to people being able to maintain their functional independence. Older people with back pain are at greater risk of falling. Neurogenic claudication will particularly affect a person’s ability to walk.12 The burden of illness associated with neurogenic claudication has been estimated to be similar to or higher than the burden associated with diabetes, heart disease, arthritis or stroke. These findings suggest that neurogenic claudication is a condition that can lead to substantial disability and health costs in older people.
Living with long-term pain will impact on psychological well-being. Depression is widespread amongst older adults living with severe low back pain. Depression is associated with the onset of back pain and the persistence of activity-restricting back pain in older adults. People with neurogenic claudication develop fear-related avoidance of activity, which contributes further to disability. Greater fear-avoidance beliefs are associated with slower gait and less functional independence in older adults with back pain.
RISK FACTORS FOR PERSISTENT LOW BACK PAIN IN OLDER ADULTS
Identifying risk factors for persistent low back pain in older adults will help to identify patients who may benefit from more intensive interventions, and help identify potentially modifiable treatment targets. Research in this area is limited, but factors associated with persistent low back pain in older adults have been identified.13
These include a range of factors across different domains:
- Demographic (female, older age, lower education level)
- Clinical presentation of back pain (greater baseline pain and disability, longer duration of symptoms, a diagnosis of lumbar spinal stenosis; comorbid pain conditions)
- Psychosocial (lower expectations of recovery, symptoms of depression and anxiety)
- General health (worse baseline health status, a greater number of comorbid health conditions, diagnosis of arthritis, a history of falls, smoking)
Many of these risk factors are similar in younger people with back pain, but some stand out as being particularly relevant to older adults. These include a history of falls and presence of comorbidity. Depression has already been highlighted as a common problem for older adults with back pain. These issues will be discussed further as we consider the impact of ageing on managing back pain in older adults. Diagnosis of spinal stenosis is also associated with poorer outcomes in older adults. We will discuss the current evidence for the rehabilitation of older adults with spinal stenosis and recommendations for improving management.
IS REHABILITATION EFFECTIVE FOR OLDER ADULTS WITH BACK PAIN?
Recent guidelines from NICE and the American College of Physicians do not separate recommendations for younger and older adults with back pain. A possible reason for this is that there is limited research specifically focusing on the management of older adults with back pain. Paeck et al. reported on the age of participants in studies of people with back pain.5 They found that the mean age of participants was 43 years of age and that the maximum tended to be around 65 years of age. There had been no significant change to this over the 20 year period they studied. Treatments, which have been tested on younger adults, may be effective in older people, but this cannot be automatically assumed as some interventions have been shown to be less beneficial in older adults. For example, a cognitive behavioral approach to treating back pain was shown overall to be effective, however, older adults did not respond as well as younger participants. 6
Exercise is recommended for managing back pain and there is limited evidence that it is effective for older adults. A variety of exercise approaches (strength training, endurance training, mixed exercise, Tai-Chi) appear to be helpful for older adults with back pain with improvements in short term outcomes including function and pain.14 Another form of exercise, Pilates, in addition to passive physical therapy has been shown to reduce pain and disability compared to passive physical therapy alone in post-menopausal women at 12 months follow up.15 However, one approach cannot be recommended over another and there is a lack of high quality trials with long term follow up on which to base recommendations.
There is little research into other types of rehabilitation approaches for older adults with back pain, resulting in insufficient information upon which to make firm clinical recommendations.
There is uncertainty around the benefits of both rehabilitation and surgical treatments for patients with neurogenic claudication. Many patients with neurogenic claudication will have surgery, but its effectiveness is unclear, and it exposes people to risk of complications including wound infection and cardiorespiratory problems. As comorbidities increase surgical risk, older people are often at higher risk than younger people. Surgery is also expensive. A course of active physiotherapy is recommended prior to surgery.16 There is a theoretical basis for recommending rehabilitation for patients with neurogenic claudication. Experts hypothesise that stretching and mobilising the spine can relieve pressure on spinal nerves and blood vessels, and aerobic exercises will improve circulation within spinal blood vessels alleviating ischaemic changes. These types of treatments are reflected in physiotherapy practice within the UK. The most common treatments for neurogenic claudication are advice/education and exercise therapy.17 Most commonly used exercises were trunk flexion exercises, muscle stability exercises and general fitness exercises. Over half the physiotherapists also routinely prescribed or suggested a walking aid for these patients. However, this approach is not supported by high quality evidence. All recent systematic literature reviews agree there is an absence of high quality trials to make recommendations about rehabilitation approaches for patients with neurogenic claudication and that more research is needed. Research studies to date have focused predominantly on altering the mechanics of spinal stenosis (such as with flexion exercises) with little regard to the psychological impact of pain or aging on participants. We will discuss the impact of ageing in the next section.
When considering rehabilitation strategies for older adults with back pain, the impact of ageing must be taken into account. This section provides a brief overview of concepts related to ageing.
Back pain does not occur in isolation. As a person gets older they are more likely to experience other health problems as well as back pain. For example, older patients presenting to primary care often have hypertension and back pain, and people with diabetes are more likely to report back pain. Depression is also a common comorbidity for people who experience chronic pain. Depressive symptoms are linked to persistence and severity of LBP in older people. People with neurogenic claudication suffer from more comorbidities than the general population including higher rates of arthritis, migraines, hypertension and incontinence. The management of back pain is often ignored or not prioritised by both patients and clinicians against a backdrop of other health conditions.18
The presence of comorbidities can make dealing with back pain more difficult. Many older adults with back pain also report other pain problems. If a person’s mobility is limited by symptoms such as knee or hip pain this can make it more difficult to follow advice to exercise and to be physically active in order to manage back pain. Patients may also be taking multiple medications (polypharmacy). Comorbidity and polypharmacy are closely linked, and polypharmacy can bring its own problems, such as drug interactions and side-effects that are more likely when many drugs are being taken.
Some older patients will have cognitive impairment or dementia. This can make the assessment of back pain more difficult, but there are pain scales for use with people with these conditions. It is important that older adults are not excluded from rehabilitation if they do present with cognitive impairment or dementia and that referrals to other appropriate services are made as well as providing management for their back pain.
Frailty and Sarcopenia
Frailty is a state of reduced physiological reserves, which leads to a person being more susceptible to adverse outcomes after an apparently minor illness or event, and is typically associated with older age. The concept of frailty includes muscle weakness (sarcopenia), slow walking speed and low levels of physical activity in its definition. Frailty and pain often co-exist in older people.
Sarcopenia is the loss of strength and muscle mass with increasing age and is an important component of frailty. Figure 11-1 shows how muscle mass and strength change over the life span and demonstrates why maintaining muscle strength is vitally important. The rate of decline of strength as a person gets older will depend upon genetics, disease and lifestyle factors.19,20 When sarcopenia is accompanied by reduced levels of physical activity, which may happen when a person has back pain, the loss of muscle and strength is accelerated. Exercise and physical activity are generally accepted to be the most important factors that contribute to maintaining muscle strength in older age, hence the rate of decline varies between people. There is a threshold of muscle mass and strength below which physical activities become very difficult or impossible; for example, a critical mass of muscle in the hip and knee extensors is needed in order to rise from a chair. As muscle mass and strength decline, levels of disability increase.
A strong body of evidence supports the hypothesis that strength training and aerobic conditioning can reverse some of the age-associated loss in physiological systems, increase the functional reserve and, in some situations, restore functional ability and reduce falls. At the moment strength training exercise is the most effective treatment for targeting sarcopenia and the subsequent loss of function associated with frailty.21
Approximately 30% of people over 65 years of age fall each year. Falls are associated with loss of independence and functional decline and contribute to the need for nursing home care in older adults. Risk factors for falling include gait and balance impairments, foot disorders, visual problems, syncope and cardiac rhythm abnormalities, polypharmacy and certain types of medication, comorbidity, and environmental hazards. Back pain is an independent risk factor for falls in the older population. The position of the centre of gravity is altered in patients with degenerative spinal conditions such as lumbar spinal stenosis. This sagittal plane imbalance has been associated with higher risk of falls in the older adult.22
Beliefs and Perspectives
Beliefs held by patients and health care professionals about pain and ageing are barriers to accessing or engaging with potentially helpful treatments.18 Some older adults believe that back pain is an inevitable part of ageing and nothing can be done.
Exercise and staying physically active are standard advice for people suffering from back pain, but it may not be easy to engage older adults in such activities. Some older people still believe that physical activity is unnecessary or even potentially harmful. Others recognize the benefits of physical activity but report a range of barriers to physical activity participation. Some older adults with chronic pain justify reducing activity levels in order to prevent pain exacerbations and the subsequent need for health-care intervention and hence preserve their autonomy. Such restrictions may be perceived as normal in older age but will contribute to the development of disability and loss of mobility.
Understanding what older adults want from back pain treatment is important. Generally, active independence is the key concern of older people. Older adults seek treatment for neurogenic claudication rated pain and limitations in function as the two biggest problems related to lumbar spinal stenosis.17 Their priorities for treatment are pain reduction and re-engagement in meaningful activities. It is important that treatment programmes reflect the priorities and preferences of patients. Older adults were questioned about the type of exercise programs they would prefer to participate in. Their preferences were home-based, no cost and guaranteed a considerable improvement in function. Fun, enjoyment, social interaction and short-term functional gains were major motivators to taking part in exercise. Barriers identified included doubts about being able to exercise or value of exercise, but these barriers were usually dispelled once people started exercising.23 Older adults seeking care for neurogenic claudication preferred a combination of one-to-one and group treatment.
REHABILITATION FOR OLDER ADULTS WITH BACK PAIN – RECOMMENDATIONS
For older adults with back pain, rehabilitation needs to be holistic and person-centred. Management strategies should take into account a patient’s general health and physical condition, their lifestyle, priorities and preferences for treatment, and their beliefs about pain, activity and ageing. Exercises may need to be tailored to accommodate comorbidities.
Promote Engagement with Rehabilitation
Clinicians should consider how to encourage their patients to engage with rehabilitation. Integral to this will be exploring priorities and preferences for treatment; thoughts and beliefs about pain, physical activity, exercise and ageing; and addressing barriers to participation. There may be a need to convince older adults that time and effort invested in managing their back pain will be worthwhile. Clinicians need to understand what is important to patients; for example, if their main concern is walking, does rehabilitation specifically address this? Improvements in outcomes such as pain or muscle strength do not necessarily translate to improvements in walking.
One consideration is the burden that rehabilitation places on a patient. Clinicians should aim to minimize burden to maximize adherence. This can be achieved by ensuring that a home exercise program is not too onerous, for example, 3-4 exercises at a maximum. Or, how many sessions does a patient need to attend? Can the patient attend group sessions or a combination of group and one-to-one sessions? Group sessions can offer several advantages, including the opportunity for social contact with peers, sharing age-related concerns with others, and a chance to give and receive feedback. Can a review be done over the telephone to minimize travel? Some patients may be carers for a family member, and this may limit their ability to attend for treatment. Transport and parking are common problems faced by older people attending hospital appointments.
An understanding of effective behavioral change strategies for use with older adults is important. The key behaviors we want to engender are participation in prescribed exercises and a sustained increase in physical activity. Clinicians should utilize behavioral change techniques that have been shown to be successful at improving self-efficacy and increasing physical activity in older adults. These include:
- Education on the positive and negative effects of physical activity
- Modeling, e.g., copying role models
- Assisting patients to plan where and when to perform their exercises
- Setting progressive tasks
- Promoting self-monitoring
- Motivational interviewing
- Barrier identification and problem solving
- Providing feedback on performance
Pain management strategies should also be utilized. This can include the use of goal setting and pacing to increase physical activity. Goals should be realistic and related to activities that are important to patients and that they enjoy. It may be necessary to target fear avoidance beliefs to address concerns about being active with pain. Educating patients about the meaning of pain and removing the threat value of pain can help patients overcome barrier to engagement with exercise or physical activity.
Build Muscle Strength and Power
At the moment strength training exercise is the most effective treatment to combat loss of muscle strength, declining function and frailty. Leg-extensor power is recognized as a critical determinant of mobility for older adults. Strength training can be done using traditional progressive resistance training approaches or it could focus on muscle power (moving a load at speed). Muscle power has been shown to have a stronger relationship with functional tests compared to muscle strength which is traditionally targeted in rehabilitation programs.24 Rehabilitation programs that incorporate power training have had superior outcomes compared to more traditional approaches. Many clinicians may not have considered including power training as part of a rehabilitation programme for older adults with back pain. However, including power training may be a way to optimize outcomes and can be incorporated into a simple exercise program.
It is important to ensure that a sufficient dose is achieved when prescribing an exercise program. The American College of Sports Medicine (ACSM) guidelines call for progressive resistance exercise to be performed on two or more non-consecutive days per week for the whole body at a moderate to vigorous level that allows 8-12 repetitions and involves exercises for all major muscle groups (8-10 exercises involving 8-12 reps each). Recent discussions have centered on how many older people find current recommendations unachievable. Patient adherence to exercise programmes is vital for their success and adherence is likely to be better with a less demanding program. Literature suggests a focus on the lower limbs to improve function. 22 Suitable exercises include sit to stand or knee extension exercises in sitting. It has been recommended that progressive resistance training, which incorporates power training once or twice per week with a single set of each exercise using even as few as one or two different exercises, may be enough to have functional gains in a frail, deconditioned population.
Ensuring that patients are working at a sufficient intensity to achieve improvements in strength and power is essential. In line with the ACSM guidelines, patients need to work at a moderate to vigorous level. Taking a pragmatic approach, we suggest starting patients at a moderate level of exercise, and this can be monitored using the Borg Rating of Perceived Exertion (RPE) Scale (Table 11-1). The Borg scale is a valid and reliable measure of exertion in resistance exercise. The patient is asked to rate their effort during an exercise using the scale. To ensure they are working at a moderate intensity, they should rate their effort as RPE 3-4. Weights may be needed to achieve the required intensity. You would aim to progress their exercises to a level of RPE 5-6 by increasing the load or adding speed to the exercise as a patient’s capacity to exercise improves. Adaptions may need to be made in response to symptoms, but this is a general guide. The number of sets and repetitions will depend on the individual patient, but we suggest starting with one set of 8-12 repetitions and building up gradually dependant on the patient’s ability and their likelihood of adhering with the prescribed program.
|Doing the exercise feels easy.
|Feels like you could just keep going with no effort.
|You are starting to feel like you are making an effort.
|You are definitely making an effort. It is feeling hard. You are starting to feel tired. You will be glad when it is over.
|You are feeling the strain.
|You are possibly feeling pain or discomfort.
|You want to stop the exercise immediately.
Restore Range of Movement
If patients present with impairments in range of movement then this can be targeted through range of movement exercises. This may be particularly important in patients with neurogenic claudication.
Restoring lumbar spine flexion for this patient group will allow the patient to do effective flexion exercises aimed at increasing the foraminal cross-sectional area to relieve pain and improve haemodynamics.8 Flexion exercises are commonly used as a pain relieving strategy for patients with neurogenic claudication.
A common impairment in older adults is loss of hip extension range of movement (ROM) during static testing and during walking.7,8 Loss of hip extension has been linked to increased risk of falling in older people.13 In patients with neurogenic claudication it has been hypothesised that loss of hip extension ROM results in an increased anterior pelvic tilt and greater lumbar extension during walking. The aim of restoring hip extension is to reduce the amount of lumbar spine extension needed to be in an upright position, therefore reducing spinal canal compromise as well as addressing age related changes. Age related changes to hip ROM can be mitigated to some degree through physical activity such as walking.17 Stretching programs targeting the hip flexor muscles can increase hip extension even in frail older people and improve gait parameters.24 This is potentially important in patients with neurogenic claudication as this should reduce the degree of lumbar extension required during standing and walking to maintain an upright position.
Interventions to improve balance often incorporate strength training so increasing muscle strength and power will potentially improve a patient’s balance.24 Gait, balance, co-ordination and functional tasks are also effective in improving balance in older people. The ACSM guidelines do not make specific recommendations regarding frequency, intensity or type of balance exercises for older people, but they do recommend activities that gradually reduce base of support, dynamic movements that perturb the center of gravity or stress postural muscle groups, and activities with reduced sensory input (e.g. standing with eyes closed). Including a balance exercise as part of rehabilitation should be considered. Along with exercise interventions, walking aid assessments should be carried out where necessary to ensure patient safety.
Aerobic exercise can reverse the decline in cardiovascular fitness associated with ageing or immobility and this is an important treatment target as better cardiovascular fitness is associated with lower risk of mortality.2
Vascular compromise contributes to symptoms in lumbar spinal stenosis. Aerobic training is thought to benefit patients with neurogenic claudication as it may help to improve vascularity of the spinal structures.17 There is little research evidence to support this but walking programs targeting aerobic fitness have been used to improve haemodynamic in patients with peripheral artery disease who experience vascular claudication. If patients with neurogenic claudication also have an element of vascular compromise then aerobic training may be of benefit. Patients with neurogenic claudication may also present with concomitant peripheral arterial disease.
Aerobic training is recommended for patients with neurogenic claudication to improve cardiovascular fitness, potentially improving the blood supply to the small vessels in the spine that are impacted by spinal stenosis and also to help treat concomitant peripheral arterial disease.16 In addition, patients with neurogenic claudication commonly report comorbidities such as hypertension and diabetes for which regular aerobic exercise is recommended.25
PEARLS AND PITFALLS
- Back pain is not a normal part of ageing, and it can be addressed.
- Managing back pain more effectively has the potential to impact on a range of health outcomes and not just the back pain.
- Rehabilitation should be holistic and integrative, address broader issues related to ageing and pain, and not be limited to the back.
- Rehabilitation should take into account patient preferences and priorities.
- Clinicians need to understand behavioral change strategies and facilitate their patients to take part in regular exercise and physical activity. This may involve addressing unhelpful beliefs about ageing and pain.
- Arthritis Research UK National Primary Care Centre. Musculoskeletal Matters. Keele:Keele University, 2010.
- Borg G. Borg's Perceived Exertion and Pain Scales. Champaign, IL: Human Kinetics, 1998.
- Kreiner DS, Shaffer WO, Baisden JL, et al. An evidence-based clinical guideline for the diagnosis and treatment of degenerative lumbar spinal stenosis (update). Spine J. 2013;13(7):734-743.
- Michie S, Rumsey N, Fussell A, et al. Improving health: changing behaviour. NHS health trainer handbook. Department of Health Publications (Best Practice Guidance: Gateway Ref 9721). Bristol:University of West of England, 2008.
- NICE. Low back pain and sciatica in over 16s. QS155. London: National Institute for Health and Care Excellence; 2017.
- Pescatello LS, Arena R, Riebe D, Paul D. ACSM’s Guidelines for Exercise Testing and Prescription. 9th ed. Philadelphia, PA: Thompson Wolters Kluwer/Lippincott Williams & Wilkins; 2014.
- Qaseem A ,Wilt TJ, McLean RM, et al. Noninvasive treatments for acute, subacute, and chronic low back pain: a clinical practice guideline from the American College of Physicians. Ann Intern Med. 2017;166(7):514-530.
- Zaina F, Tomkins-Lane C, Carragee E, Negrini S. Surgical versus non-surgical treatment for lumbar spinal stenosis. Spine (Phila Pa 1976). 2016;41(14):E857-68.
- Patel KV, Guralnik JM, Dansie EJ, Turk DC. Prevalence and impact of pain among older adults in the United States: findings from the 2011 National Health and Aging Trends Study. Pain. 2013; 154(12):2649-2657.
- Macfarlane GJ, Beasley M, Jones EA, et al. The prevalence and management of low back pain across adulthood: results from a population-based cross-sectional study (the MUSICIAN study). Pain. 2012;153(1):27-32.
- Shega JW, Dale W, Andrew M, Paice J, Rockwood K, Weiner DK. Persistent pain and frailty: a case for homeostenosis. J Am Geriatr Soc. 2012; 60(1):113-117.
- Makris UE, Fraenkel L, Han L, Leo-Summers, Gill TM. Restricting back pain and subsequent mobility disability in community-living older persons. J Am Geriatr Soc. 2014; 62(11):2142-2147.
- Paeck T, Ferreira ML, Sun C, Lin CW, Tiedemann A, Maher CG. Are older adults missing from low back pain clinical trials? A systematic review and meta-analysis. Arthritis Care Res (Hoboken). 2014;66(8):1220-1226.
- Underwood M, Mistry D, Lall R, Lamb S. Predicting response to a cognitive-behavioral approach to treating low back pain: secondary analysis of the BeST data set. Arthritis Care Res (Hoboken) 2011;63(9):1271-1279.
- Gellhorn AC, Katz JN, Suri P. Osteoarthritis of the spine: the facet joints. Nat Rev Rheumatol 2013;9(4):216-224.
- Schönström N, Lindahl S, Willén J, Hansson T. Dynamic changes in the dimensions of the lumbar spinal canal: an experimental study in vitro. J Orthop Res. 1989;7(1):115-121.
- Suri P, Rainville J, Kalichman L, Katz JN. Does this older adult with lower extremity pain have the clinical syndrome of lumbar spinal stenosis? JAMA. 2010;304(23):2628-2636.
- Boden SD, Davis DO, Dina TS, Patronas NJ, Wiesel SW. Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. A prospective investigation. J Bone Joint Surg Am. 1990;72(3):403-408.
- Rundell SD, Sherman KJ, Heagerty PJ, Mock CN, Jarvik JG. The clinical course of pain and function in older adults with a new primary care visit for back pain. J Am Geriatr Soc. 2015;63(3):524-530.
- Wong AY, Karppinen J, Samartzis D. Low back pain in older adults: risk factors, management options and future directions. Scoliosis Spinal Disord. 2017;12:14.
- Rundell SD, Sherman KJ, Heagerty PJ, et al. Predictors of persistent disability and back pain in older adults with a new episode of care for back pain. Pain Med. 2017;18(6):1049-1062.
- Kong LJ, Lauche R, Klose P, et al. Tai Chi for chronic pain conditions: a systematic review and meta-analysis of randomized controlled trials. Sci Rep. 2016;29:6:25325.
- Cruz-Diaz D, Martinez-Amat A, Osuna-Perez MC, De la Torre-Cruz MJ, Hita-Contreras F. Short- and long-term effects of a six-week clinical Pilates program in addition to physical therapy on postmenopausal women with chronic low back pain: a randomized controlled trial. Disabil Rehabil. 2016;38(13):1300-1308.
- Genevay S, Atlas SJ. Lumbar Spinal Stenosis. Best Pract Res Clin Rheumatol. 2010;24(2):253-265.
- Backstrom KM, Whitman JM, Flynn TW. Lumbar spinal stenosis-diagnosis and management of the aging spine. Man Ther. 2011;16(4):308-317.
- Makris UE, Higashi RT, Marks EG, et al. Ageism, negative attitudes, and competing co-morbidities--why older adults may not seek care for restricting back pain: a qualitative study. BMC Geriatr. 2015;8:15-39.
- Sayer AA, Syddall H, Martin H, Patel H, Baylis D, Cooper C. The developmental origins of sarcopenia. J Nutr Health Aging. 2008;12(7):427-432.
- Venturelli M, Schena F, Richardson RS. The role of exercise capacity in the health and longevity of centenarians. Maturitas 2012;73(2):115-120.
- Liu CJ, Latham NK. Progressive resistance strength training for improving physical function in older adults. Cochrane Database Syst Rev. 2009;(3):Cd002759.
- Kim HJ, Chun HJ, Han CD, et al. The risk assessment of a fall in patients with lumbar spinal stenosis. Spine. 2011;36(9):E88–592.
- Franco MR, Tong A, Howard K, et al. Older people's perspectives on participation in physical activity: a systematic review and thematic synthesis of qualitative literature. Br J Sports Med. 2015;49(19):1268-1276.
- Byrne C, Faure C, Keene DJ, Lamb SE. Ageing, muscle power and physical function: a systematic review and implications for pragmatic training interventions. Sports Med. 2016;46(9):1311-1332.
- Battié MC, Jones CA, Schopflocher DP, Hu RW. Health-related quality of life and comorbidities associated with lumbar spinal stenosis. Spine J. 2012;12(3):189-195.