A primary care approach to the management of Arthritis

Arthritis is a common condition seen frequently by family practitioners, and there are many types of arthritis. Management of arthritis depends largely on the specific type of arthritis that the patient suffers from. In this article, we will provide the primary care doctor with practical information for managing arthritis, focussing on the management of osteoarthritis and rheumatoid arthritis.


Introduction
The term 'arthritis' refers to the swelling of a joint or joints with associated limitation of movement, heat, pain or tenderness, which is caused by inflammation or degeneration of one or more joints. 1 It is a common cause of disability that impairs one's physical and mental well-being, thus being a major burden on healthcare and economic resources. 2 In the United States, the prevalence rate of self-reported arthritis is estimated to be about 59.4 million people, 3 and the condition is a leading cause of major disability in the United Kingdom. 4 There is a paucity of prevalence data in Africa. In South Africa, osteoarthritis is the most prevalent form of arthritis, with a prevalence rate of 55.1% in urban settings, and between 29.5% and 82.7% in adults over 65 years of age in rural settings. 5 Arthritis is the pathological feature in over 100 different chronic diseases involving the joints and connective tissues, with the most common forms being osteoarthritis, rheumatoid arthritis (RA) and ankylosing spondylitis. Less common forms of arthritis include systemic lupus erythematosus, scleroderma, psoriatic arthritis and gout. 6 The three major physiological categories of arthritis include inflammatory (rheumatoid), degenerative (osteoarthritis) and crystal-induced (gout) arthritis. The inflammatory arthritides can be further subdivided into RA (and related disorders) and connective tissue disorders. 7 Although arthritis may be monoarticular or polyarticular, all types may be monoarticular early in the pathological course. 7 Therefore, clinical information and imaging studies are crucial in differentiating between the different types of arthritides (Table 1).
When approaching musculoskeletal pain, differentiating between articular and non-articular or diffuse pain narrows the differential, and this is based on history and examination ( Figure 1). Articular pain in comparison to non-articular pain is more diffuse and present in both active and passive movements, while non-articular pain is usually localised to the affected structure (e.g. muscle, tendon, bursa, fascia, nerve or bone) and usually limits active rather than passive movements. In non-articular pain joint crepitus, deformity or instability is absent but muscle weakness and wasting may be present. 8,9,10 Damage to the cartilage causes the tissues within the joint to become active, altering its structure, resulting in pain, stiffness and restricted range of movement. Osteophytes develop at the edge of the joint while the synovium thickens and fluid accumulation causes swelling ( Figure 2). 13

Symptoms and signs
The main symptoms of osteoarthritis are pain and sometimes stiffness in the affected joints. The pain tends to be worse when the joint is moved or at the end of the day. Stiffness occurs at rest and usually improves with activity. 15 The swelling may be hard and knobbly, which is caused by the growth of extra bone, or it may be soft, which may be caused by the thickening of the synovium and extra fluid inside the joint capsule. 16 Crepitus is a common sign of osteoarthritis. Muscle wasting around a joint is a late feature.

Diagnosis
The diagnosis of osteoarthritis is predominantly clinical based on a good history and physical examination. Plain radiological procedures may confirm diagnosis or rule out other medical conditions. 17  1: Approach to musculoskeletal pain. 8,9,10 https://www.safpj.co.za Open Access

Management
The management of osteoarthritis encompasses both pharmacological and non-pharmacological options involving the patient in decision-making that incorporates adherence and self-management.
Key non-pharmacological interventions include arthritis education, land-based exercise programmes and weight reduction. Optional non-pharmacological interventions include heat therapy, manipulation and massage, transelectrical nerve stimulation (TENS) and water-based exercises. These can be tried according to patient preferences and stopped if found to be ineffective. 18 The popularity of paracetamol has decreased with new studies questioning the safety profile in comparison to the minimal efficacy it produces. 19 However, it is reasonable to trial paracetamol at a dose of up to 3 g/day and discontinue if no response is achieved.
Topical and oral non-steroidal anti-inflammatory drugs (NSAIDS) form the backbone of pharmacological interventions for osteoarthritis. While all NSAIDS share similar efficacy, individual sensitivities may differ. In principle, the lowest dose should be used for the shortest period of time to achieve a clinical response to balance the risk of long-term use.
Comorbid conditions should be factored in when prescribing NSAIDS as they are cardiotoxic, nephrotoxic and cause peptic ulceration. 20 The conditions for co-prescribing NSAIDS with a PPI and using a selective COX-2 inhibitor are outlined in Figure 3.
Opioids provide marginal efficacy for joint pain but carry a serious risk of abuse, tramadol can be used in certain instances, while other opioids in general should be avoided. Intra-articular steroids are of significant benefit during an acute flare for short-term pain relief. However, repeated injections may result in rapid cartilage loss with no long-term benefit and hence judicious use is warranted. 21 Figure 4 compares four international guidelines for osteoarthritis management of the knee. The American College of Rheumatology (ACR) published guidelines in 2012 for knee, hand and hip osteoarthritis. 18 The American Academy of Orthopaedic Surgeons (AAOS) in 2013 laid out guidelines for non-surgical management of osteoarthritis of the knee. 22   https://www.safpj.co.za Open Access

Rheumatoid arthritis
Rheumatoid arthritis is a systemic autoimmune condition, which causes pain, swelling and stiffness of multiple joints of the body. 25 Tiredness, lack of energy, weight loss, fever, sweating and dry eyes may manifest with systemic involvement. Clinical features are outlined in Table 1.
Autoimmunity and overall systemic and articular inflammation are responsible for the destructive progression of the disease. 26 Joint capsule instability results as the surrounding joint ligaments become weakened and stretched ( Figure 5). 27

Diagnosis
Assessment of the patient is based on clinical history and physical examination. The pain of arthritis is the factor that causes patients to frequently seek healthcare. Characteristics such as location, quantity, intensity, nature and the course of pain can assist diagnosis. Other symptoms of arthritis include stiffness, limited motion, fatigue, weakness and swollen joints. The latter can be assessed by inspection or by direct palpation of the joint. A count of the number of swollen joints provides an indication of the amount of inflamed tissue. Use of diaries could prove a useful adjunct to traditional methods of pain assessment (e.g. visual analogue scales) and can incorporate ratings of stiffness, fatigue and mood. 27 Early diagnosis and initiation of treatment or referral to a physician is key in the prevention of severe disability and the loss of quality of life. 27 A joint working group of the ACR and the European League against Rheumatism (EULAR) developed updated criteria to assist in making diagnoses earlier (Table 2). 26 Application of these criteria provides a score of 0-10, with a score of 6 or more out of 10 being indicative of the presence of definite RA.
General laboratory tests can help determine whether arthritis and its treatment have affected major body systems. A full blood count may reveal the presence of anaemia of chronic disease, a common feature of arthritis. Neutropenia is often associated with severe RA. Liver function tests and viral serology are essential prior to commencement of treatment. 26 In RA, 80% of patients will test positive for rheumatoid factor. Positive rheumatoid factor and anti-citrullinated peptide antibody tests are associated with increased disease severity, the development of erosions, extra-articular manifestation and greater disability. Levels of acute phase reactants (e.g. C-reactive protein and erythrocyte sedimentation rate) are used to monitor disease activity. 23,25 Radiography, or X-rays, is helpful both diagnostically and in monitoring the disease progression.

Management of rheumatoid arthritis
The management of RA has changed dramatically over the past 30 years. 28 The fundamental principles revolve around   https://www.safpj.co.za Open Access disease control within 3-6 months, with the goal being remission or a low disease activity state. 28 The 2016 update of the EULAR recommendations is based on recent evidence in the area of RA management. 29 The principles explain the importance of early referral to a rheumatologist (or family physician or internal medicine consultant in settings with restricted access, such as the South African district health system) so that targeted therapy can be initiated based on the principles of monitoring disease activity and shared decision-making.
The recommended target is to reach a state of sustained remission or low disease activity using standardised scoring systems like the disease activity 28 joint score (DAS28). Methotrexate (MTX) is the initial drug of choice if not contraindicated. It is a conventional synthetic diseasemodifying antirheumatic drug (csDMARD). A trial period of 3 to 6 months is the goal before treatment is adjusted according to the degree of improvement.
A second-line drug like another csDMARD (e.g. leflunomide or sulphasalazine) may be added in the presence of poor prognostic factors. Biological drugs (e.g. etanercept) may be added to csDMARDS until remission before the former is weaned off and then the latter.
Biologicals should be co-prescribed with a csDMARD in most cases. It is not advisable to combine two biologicals. Once remission is obtained, first wean off the biological and then the csDMARD.
A multidisciplinary approach through networking with allied health disciplines like physiotherapy, occupational therapy, podiatry and dietetics is essential to reach goalorientated targets. 8 Patient education directed at strengthening social and emotional support to enhance self-management of pain and disability as well as adherence to health recommendations is essential. 25

Summary
The basic management for some of the other common arthritis is detailed in Table 3.

Conclusion
While arthritis is common and the differential diagnosis is broad, having a well-rounded approach and holistically managing a patient, including timely referral for the inflammatory forms of arthritis, will result in better patient outcomes, better quality of life and decreased morbidity.