Non-Operative Management of Knee Osteoarthritis Disability

Keywords

Aging; Disability; Management; Knee Joint Osteoarthritis; Outcomes.

Introduction

Osteoarthritis, the most common rheumatic disease, is a chronic non-fatal condition with significant individual, social and economic ramifications [1-3]. Principally due to localized disruptions in the articular cartilage tissue lining all freely moving joints of the body, osteoarthritis often causes varying degrees of painful mechanical dysfunction [2] that can severely impair an individual's ability to function physically without compromise [3]. Unfortunately, while useful in restoring function and ameliorating pain in severe cases of the disease, not all cases of osteoarthritis may be amenable to artificial joint-replacement surgery, especially if multiple joint sites are affected. Reducing osteoarthritic pain by means of analgesic medication and non-steroidal anti-inflammatory drugs, also frequently proves ineffective or harmful [2].

In seeking to assist people with osteoarthritis, who are frequently 60 years or older, to meet the challenges of daily life as optimally as possible, a wide array of adjunctive methods other than medications, or surgery that might reduce the pain and disability associated with osteoarthritis, and are cost effective, have consequently been advocated. Yet, while somewhat effective in selected cases, patients may report not being sufficiently educated about the disease and its treatment options, and prognosis [4]. Many too, may not employ or engage in any non-pharmacologic strategy even though these are recommended before surgical treatment options are considered [5]. With few definitive studies that have examined the application of personalized comprehensive evaluations followed by carefully construed and selected strategies on the disease outcome, both clinicians as well as patients may not feel confident in generalizing the idea of conservative treatments for treating osteoarthritis. Patients who are aware, may also vary widely even if they have the same diagnosis, thus careful tailoring of recommendations is indicated. Patients especially, may not be sufficiently enthused towards applying the principles of disease self-management [6] if their providers do not mention the importance of this approach.

Since there is increasing evidence that the rates of disability produced by osteoarthritis are not inevitable, but that lifestyles and behaviours have powerful influences as well, the objective of this brief was to review the chief characteristics of osteoarthritic joint disease, especially components of the disease that might be positively affected by one or more non-pharmacologic strategies, and to consider how knee osteoarthritis, the most common form of the disease, might be managed effectively by conservative nonpharmacologic approaches given that these are cost-effective and often successful [7]. Although directed towards a conservative prescription for the management of knee osteoarthritis, the most important causes of pain and physical disability in the community [8], the therapeutic rationale outlined should be applicable to other joint sites commonly affected by osteoarthritis.

To this end the PubMed, Scopus, and Web of Science data bases between 1990-2015 were examined using key words, osteoarthritis, knee joint, self-management, treatment. Although some work has been implemented to systematically review the research in this realm, most studies are somewhat flawed, focus on diverse topics, samples, and joint status, precluding any useful quantitative synthesis at the present time. The data extracted were hence categorized according to the disease itself, and those research data that could be used to address the perspective of self-management as a component of conservative and surgical interventions, rather than clinic based therapies.

Osteoarthritis

Osteoarthritis, often neglected as a serious health condition, produces an untold burden and costly outcome for adults of all ages, especially the elderly. Although the pathology of osteoarthritis, which entails the presence of focal or complete lesions of the articular cartilage lining of one or more joints, as well as various degrees of bone remodelling and exposure of underlying bone, is well established, and accumulated knowledge shows some of this disability is amenable to prevention or intervention, very few preventative efforts to counter these changes exist. One reason for this may be a failure of clinicians and others to carefully scrutinize the available current research, and to rely on historical myths that osteoarthritis is inevitable and irreversible, and that radiological joint changes equate to clinical osteoarthritis (See Box 1). Hence, both persons with the condition as well as their providers may simply believe the disease is inevitable, and that thoughts of reversing this condition are ‘heresy’. As a result, in addition to neglecting the idea that chondrocytes can respond favourably to optimal intracellular signals, other pathological features of the disease process such as various degrees of joint capsular and synovial membrane thickening, joint inflammation, ligament and tendon damage, and muscle pathology and atrophy, which may respond to targeted treatments, may go untreated and as a result may hasten chondrocyte cell death and ensuing joint destruction processes [9].

This is unfortunate because as a result of the above mentioned pathological changes and others, the hallmark symptomatic feature of osteoarthritic destruction, namely pain, may be unremitting and accompanied by extended periods of joint stiffness after rest, which may last longer than 30 minutes; the possible onset of diminished or excessive joint range of motion, joint tenderness, joint crepitus or ‘locking’ on motion, variable degrees of joint inflammation, and joint swelling [8]. There may also be a decline in joint stability and overall function, plus evidence of irreversible joint deformity and malalignment. Anxiety, depression, and impaired psychosocial functioning, along with a decreased selfimage are also frequent undesirable outcomes of osteoarthritis, as are impairments of general health, and vitality [10]. Consequently, although not usually fatal, the signs and symptoms of osteoarthritis may severely reduce the ability of an individual to carry out his or her normal activities of daily living without undue stress [11], and may limit work capacity and wage earnings quite considerably [12]. In the geriatric years, the disease may seriously compromise life quality [10] and the ability to live independently and carry out self-care activities [8].

On the other hand, results of some in vitro studies provide tentative evidence that the abnormal biochemically and biomechanically mediated cell-matrix interactions of osteoarthritic cartilage that usually result in an overall loss of its compressive stiffness and elasticity [13], may be part of an attempted reparative process [14]. In particular, because mechanical stimuli are essential for the growth and maintenance of cartilage and aberrant mechanical loading can lead to cartilage damage, it appears that careful mechanical manipulation of the cell micro-environment may arguably help to foster tissue reconstitution and reduce cartilage matrix damage attributable to the release of degradative enzymes by damaged cartilage cells [15]. This is supported by numerous loading studies ranging from immobilization to excessive weightbearing [16] and others that imply that excessive repetitive impacts or preventable mechanical insults might potentiate cartilage damage or render the bone beneath this tissue noncompliant [16].

In sum, osteoarthritis may not be inevitable, in all cases, and even when present may be amenable to amelioration if careful evaluations followed by carefully construed and timely treatment strategies are forthcoming.

Knee Osteoarthritis

The knee, a commonly involved joint affected by osteoarthritis [8], is a frequent source of functional disability and pain [17], especially in the elderly [18] and women who may have decreased survival rates [19]. Linked strongly with bone marrow lesions [20], and obesity in bilateral cases and knee injury in unilateral cases [21], the individual and collective socio-economic impact attributable to knee osteoarthritis is considerable [22].

As with osteoarthritis in general, knee osteoarthritis is commonly accompanied by one or more of the following disabling signs and symptoms: knee pain on motion, decreased knee range of motion, knee muscle weakness, knee joint swelling and inflammation, instability and deformity [23-27]. Also frequently evident are gait abnormalities [28], a diminished aerobic capacity [29], and limitations in function with respect to rising from a chair, stair climbing and squatting [30].

Contributing to these clinical problems may be several physical factors including abnormalities in the motor unit physiology of one or more of the knee extensor muscles. There may also be extensive knee extensor muscle pathology, a very high rate of knee extensor muscle protein degradation and related problems of impaired knee proprioception, knee muscle inhibition due to swelling, and postural instability [32-37] plus loss of functional independence [38].

Fortunately, there is evidence that most individuals with knee osteoarthritis can be treated reasonably successfully by sustained adherence to a well-designed conservative management program, including patient education, nutrition counselling, exercise instruction, and home and work modifications [7], especially if these interventions are implemented in the early phases of the disease [39]. Moreover, the degree of disability arising from knee osteoarthritis may not be inevitable if carefully construed efforts to minimize future joint insults, increase surrounding muscle strength and power, and reduce pain and inflammation are forthcoming.

Management Strategies

In light of the possibility that osteoarthritic cartilage repair processes may exist [40], non-pharmacological and non-operative interventions that carefully consider all possible pathogenic mechanisms that contribute to the disease, may merit investigation [41]. They may also be effective for reducing functional limitations and disability, the health factor of most concern to patients [42].

In particular, given that subnormal joint loading mechanisms strongly influences the osteoarthritis disease process [43], eliminating the most detrimental forces falling on the joint surface, as well as improving the ability of the surrounding tissues to absorb, distribute and respond to mechanical forces more physiologically, is likely to prove especially helpful, irrespective of causative mechanism [44]. Encouraging movements to optimize a healthy joint range of motion and facilitate joint nutrition might also be expected to similarly promote some degree of cartilage repair or reversal of cartilage catabolism, while relieving pain and enhancing quality of life, particularly during the early stages of the disease process [45].

Interventions in this respect might include a variety of joint protection and energy conservation strategies, exercise regimens, and the application of a variety of physical modalities that relieve pain and enhance muscle function and intermittent joint compression. Moreover, being active and productive, and keeping a healthy weight is likely to prove more useful than not.

To ascertain what might produce the most optimal result for an individual, the clinician can help by undertaking a thorough history and physical examination before ascertaining whether the intervention aim is to achieve: 1) a reduction in knee joint pain, knee muscle spasm and/or swelling, 2) an increase in knee mobility, stability, strength, endurance, proprioception, balance control and/or gait efficiency, and/or 3) optimal aerobic fitness or weight control. They can also conduct a mental health screening test to examine whether depression, anxiety, or stress are likely to be factors requiring additional intervention attention. Ascertaining the magnitude of the osteoarthritic condition, and the client’s general health status will also be helpful, along with other measures depicted in Box 2.

Treatment Approaches

Education

Regardless of the aim of any therapeutic strategy, because both helplessness and a lack of education appear to be highly important, potentially treatable factors in determining the extent of knee osteoarthritis disability [46], patient education is highly recommended [47]. In addition to explaining the general principles discussed previously, the educational component for knee osteoarthritis should address the need to balance rest with activity.

To effectively meet the goals and objectives of educating the patient about his or her condition, the selected approach developed in conjunction with input from the patient should help to: (a) promote adoption of any desirable or required novel behavior(s), (b) facilitate adherence and maintenance of the behavior(s); (c) prevent relapse of unhealthy behavior(s) [48]. Desirable educational interventions likely to be most effective are those that employ a skilled empathetic interventionist with a positive outlook, and the use of behavioral contracting, generalization training, and commitment strategies. Written exercise and/or nutrition instructions and others with diagrams understandable by both the patient and their significant others are especially important. Finally, to mitigate the impact of depression due to the disease chronicity, helping to build the patient’s confidence by enacting small achievable steps and appropriate feedback as outlined by self-efficacy theory [49], plus emotional support for both patients and caregivers has been recommended in educational programming [50].

Joint protection strategies

Although there is little empirical evidence to support the implementation of joint protection and energy conservation strategies for knee osteoarthritis [51], appliances such as canes [51] and unloader braces, and neoprene sleeves or splints may help to protect the joint from excessive stresses [52]. Such devices are particularly valuable in the presence of muscle weakness, malalignment and instability of the lower leg. Likewise, orthotic devices that facilitate or improve function by fostering the favorable application of biomechanical forces and hence the magnitude of joint stresses falling on the medial or lateral compartments, may be of benefit [53], as may the use of well-cushioned shoes [51]. Other modalities that may afford joint protection secondarily include interventions such as patellar taping [54] and insoles [55]. For overweight individuals, weight loss to reduce the impact loads at the knee and poor knee muscle function that can cause further joint damage may help slow the progression of knee osteoarthritis [56].

In addition to the previously mentioned strategies, educating the patient about the adverse impact of engaging in prolonged periods of standing, kneeling and squatting, walking at rapid speeds and engaging in sports or work activities that increase stress on the joint or involve jarring or unexpected movements, as well as fatiguing activities is recommended [53]. Avoiding the use of stairs and low chairs, showering instead of bathing, or using aids to minimize joint forces generated by these activities is also desirable. To minimize joint stress and conserve energy, a well-planned well-organized work space that facilitates use of efficient body mechanics and includes periods of rest coupled with periods of modest activity during the day is also advocated. However, completely unweighting the joint for example for exercise purposes may not prove effective in decreasing pain in the long term [57].

Physical modalities

Because of the strong possibility that muscle may be implicated in some aspects of the osteoarthritic disease process at the knee, physical interventions other than exercise that improve muscle function may prove beneficial. These include modalities that can be applied at home such as ice [58], heat [59], and electromyographic biofeedback-controlled exercise training that uses an audio or visual signal to provide feedback on the prevailing versus the desired muscle functional outcome, [60] and can reduce muscle spasm and pain. In addition, transcutaneous electrical stimulation treatments, that uses an electrical current and small electrodes attached to a portable transmitter to override pain signals in around the affected joint[s] can help to improve functional status, and for those who incur too much discomfort with active exercises electrical muscle stimulation may provide an appropriate alternative to this form of activity [61].

Exercises

Knee joint proprioception, muscle reflex activation, strength, and joint range of motion and stability, all compromised in knee osteoarthritis, may all be improved by carefully designed therapeutic exercises, such as strength training, range of motion exercises, stretching, and postural exercises [62, 63]. In turn improved muscle strength may also foster bone mineralization, cartilage repair [62], endorphin production [62], and central factors known to affect peripheral pain, such as anxiety [62, 64]. Other physiological benefits of therapeutic strengthening exercise for the osteoarthritic knee include increments in the tensile strength of the surrounding joint capsular, tendon and ligamentous tissues [17], improved post-exercise joint blood flow and cartilage nutrition [65], venous and lymphatic return [66] and synovial blood flow [67].

However, although most studies report a positive effect on pain or disability regardless of exercise protocol [68], recommendations for exercise may not be forthcoming, and thus patients may not find their condition is improving [69]. Others may not consider the importance of acknowledging osteoarthritic complications such as joint effusion, muscle pathology, instability, and fatigue [70] in detrimentally influencing the outcomes of any exercise prescription [71]. Many patients too may have high blood pressure, which may not be well controlled, and caution is hence advised in prescribing exercises to these individuals, without careful deliberation and instruction. Similarly, care must be taken to caution those with knee hypermobility or instability about the consequences of overstretching, and incurring fatigue.

To be effective, exercise prescriptions should also take into account the individual's personal needs, preferences and interests, as well as their psychosocial status, and perceived self-efficacy for undertaking exercises and for achieving successful outcomes as discussed by Kovar et al. [72]. Cross-training or exercising at various muscle lengths, speeds and intensity, may also allow exercises carried out to have both specific positive, as well as generalized benefits [67, 73]. Because compliance with exercise has been found to improve if exercise is perceived as recreational, the use of a warm pool or group exercises with musical accompaniment has been recommended [74].

In short, unlike medications which do not reverse the disease process [76], a significant proportion of cases with knee osteoarthritis studied to date are likely to show adequate symptom relief in response to one or more conservative therapeutic approaches such as weight loss, exercise, the use of physical modalities [77], efforts to optimize joint biomechanics [78], and self-efficacy [79]. In contrast, a lower life quality, and more rapid extensive pathology and disability is likely to ensue by failure to follow a long-term regime of joint protection, exercise, and weight control, regardless of whether or not pharmacolic and/or surgical strategies are indicateds.

Conclusion

Osteoarthritis, a common painful disabling disease, frequently affecting the knee joint, often thought to be untreatable, can be favourably impacted by a variety of conservative management approaches applied alone, or in combination, including, but not limited to, patient education, weight reduction, the appropriate application of assistive devices and orthotics, exercises to maximize muscle strength and endurance, joint range of motion and aerobic capacity, among others. That is, carefully tailored and personalized uni-or multicomponent approaches recommended in light of the extent of prevailing joint destruction, and the patient’s age, health status, beliefs, fears, anxieties, and general capabilities for self-management can potentially yield quite favorable rather than unfavourable disease outcomes [75, 98].

However, because pain relief that leads to excessive joint use could have adverse effects on damaged cartilage [80], a structure very sensitive to mechanical signals [81], enabling the patient’s understanding of all potential contributing factors to the prevailing structural damage and dysfunction, such as loading magnitude and frequency [81], is desirable in efforts to reduce their pain and prevent excess disability, while promoting independence, as well as life quality [82, 83] as outlined in Figure 1.

In particular, educating the patient to assert control over their disease, and that excessive fatigue can have a highly negative impact on the patient’s life [84] is as important as helping patients to pursue realistic treatment goals and expectations. In addition, efforts to avoid injury and/or excessive loading of an osteoarthritic knee, especially if a sensory deficit prevails [85] should be stressed. Making patients aware that their own self-management practices may not only benefit joint regeneration processes [86], but may minimize the degree of any associated inflammation [87-89], while improving their life quality, is also of great import in efforts to foster adoption and adherence of self-management recommendations as outlined by Smith et al. [6]. Finally, dispelling the myth that osteoarthritis is inevitable, and revealing the promising results of many current non-pharmacologic intervention studies when viewed independently [e.g. [7, 76]], along with their low risks of side-effects or long term health concerns, might provide patients as well as providers with a strong rationale for pursuing and adhering to such programs.

In this regard, given the failure of prevailing pharmacologic and surgical interventions to prevent disability in all cases, future research to investigate the long-term benefits of the various conservative intervention approaches that have shown promise to date or have been discussed in the related literature should be explored further [eg [90-97]]. As well, whether any of these recommended approaches can assist in efforts to improve cartilage regeneration efforts [86] and can minimize inflammation that can worsen structural damage [87], while improving the mechanical environment of the knee joint [57], also awaits further research.

However, as discussed by Roos and Arden [90] it is the present author’s view that to correct or attenuate osteoarthritic symptomology, efforts to examine exactly what is most appropriate as well as acceptable for the individual patient, followed by well construed education and provision of resources and prescriptive advice will markedly optimize adherence to-and persistence withthese regimes. It is also the author’s view that even if such an approach does not prevent the progression of the disease or reverse it, health status as a whole is likely to be more positively impacted than not by employing these aforementioned non pharmacologic self-management directives as outlined by Haung et al. [91], Anwere [92], Harris and Crawford [93].

As outlined by Walker [97], for many older people with knee osteoarthritis, the ability to engage or not engage in meaningful social actions and functional activities promises to be ably facilitated by the strategies discussed in here, including a holistic assessment and tailored interventions as outlined Box 2 and Figure 1. Other non-pharmacoligic approaches not discussed here that depend on more passive strategies or group activities among others, should also not be overlooked.

×

Figure

Close

Figure 1. Possible multipronged approaches that can offset knee osteoarthritis disability [7, 75, 96]