Top Tips: Joint Pain

Dr Louise Warburton Offers 10 Top Tips on the Diagnosis and Management of Joint Pain in Primary Care

Around 17–30% of GP appointments in the UK are for musculoskeletal problems;¹ demand is growing, with £141 million spent annually on GP consultations for back pain.² Inevitably, any GP or primary care healthcare practitioner is going to come across a patient experiencing joint pain. This article focuses on how to assess, diagnose, and manage joint pain in primary care. 

1. Take a Good History

The first step in any assessment is to take a good history from the patient. Anecdotally, more than 80% of the diagnosis can be reached by careful questioning alone. Since the COVID-19 outbreak and the increasing use of video and telephone assessment, this history-taking is even more important as physical assessment is often impossible. Ask the patient:

• how long has the pain been present?
• how did the pain start?
• was it insidious, or sudden and due to an injury?
• how does the pain affect you? (Elicit ideas, concerns, and expectations [ICE].)

2. Find Out Exactly Where the Pain is Experienced

A lot of people will describe pain in their arms or legs, and do not actually mean ‘joint pain’. It is very important to assess whether the joints are actually the cause of pain: pain within a joint and swelling indicates the possibility of inflammatory arthritis. Aching in muscles, and tenderness to touch in the skin, is more likely to indicate a chronic pain state or fibromyalgia.

Patients with fibromyalgia experience abnormal pain sensations such as dysaesthesia, an abnormal and unpleasant sensation in the skin. There is heightened sensation of touch, and the sensation is unpleasant; a patient may describe standing under the shower and finding the water stream painful. This indicates that they have either experienced an area of denervation and the nerve is recovering and producing dysaesthesia, or if widespread, could indicate a pain syndrome such as fibromyalgia.³

Another sensory abnormality in fibromyalgia and chronic pain states is ‘hypervigilance’, which contributes to sensory overload. The brain becomes overly sensitive to stimuli such as sounds, bright lights, touch, and painful sensations; these states of hyper-arousal are exhausting for the patient and contribute to the fatigue experienced.^4,5

3. Determine the Exact Anatomical Location of the Problem

Pain can be referred: pain in the arm may actually be caused by a problem in the neck, such as a prolapsed disc, and this would be a radiculopathy. Pain felt in the leg can be referred from the spine (for example, sciatica).

Referred pain is often felt in the dermatomal distribution of the nerve which is being compromised: arm pain felt because of a C6/7 disc prolapse is felt in the C6/7 dermatome in the thumb and radial side of the hand. It is therefore important to establish whether the pain is due to a local problem or is referred.

4. Ask What Time of Day is Worse for the Pain

Inflammatory pain, such as that due to rheumatoid arthritis (RA) or other types of inflammatory arthritis, will be worse in the morning after sleep and after a period of inactivity. It is normally thought that 30 minutes or more of early morning stiffness is significant and indicates an inflammatory cause. A few minutes of pain and stiffness is common in degenerative causes of joint pain such as osteoarthritis (OA).

5. Ask About Joint Swelling and Tenderness

Has the patient had any definite joint swelling? Vague descriptions of fingers feeling swollen or fat are probably not significant. Sometimes a patient will have taken photos of their swollen joints on their mobile phones, and this can be very useful.

Does your patient have palpable joint swelling or tenderness, especially in the hands or feet? This is probably significant if present and indicates synovitis; see metacarpal squeeze tests.⁶

In RA, the inflammation is usually symmetrical and starts in the small joints of the hands and feet. As mentioned above, early morning stiffness is a feature; if this lasts more than 30 minutes it is thought to be significant. Lesser degrees of stiffness are seen in degenerative conditions such as OA.

For further information, refer to the Royal College of General Practitioners’ (RCGP) e-learning suite, where Versus Arthritis and RCGP have published a Core skills in musculoskeletal care e-learning package.⁷

6. Be Alert to Joint Pain that Suggests an Inflammatory Cause

NICE Quality Standard 33,⁸ based on guidance in NICE Guideline 100,⁹ recommends in statement 1 that: ‘Adults with suspected persistent synovitis affecting more than 1 joint, or the small joints of the hands and feet, are referred to rheumatology services within 3 working days of presenting in primary care.’

NICE Guideline 100 is specific in recommending immediate referral before waiting for the results of any blood tests or investigations (See Box 1).⁹

Immediate referral is recommended with no delay to wait for investigations, but it is useful for a rheumatoid factor test and an anticyclic citrullinated peptide (anti-CCP) measurement to be carried out.¹⁰ Rheumatoid factor is positive in about 70% of people with RA. The other 30% will still have inflammatory arthritis but it is called sero-negative rheumatoid.¹¹

If a person is negative for rheumatoid factor, but has a positive anti-CCP, they have the potential to develop RA at some point in the future.¹²

7. Remember That Not All Joint Pain is Due to Synovitis

Pain around a joint can be due to inflammation of tendon sheaths (tenosynovitis) or inflammation at the point where tendons attach to bones (enthesitis).

Enthesitis is a characteristic of the spondyloarthritis group of diseases, which include: reactive arthritis; psoriatic arthropathy; arthritis associated with inflammatory bowel disease; and axial spondyloarthropathy (previously called ankylosing spondylitis).^13,14

The features of this group of diseases are quite wide-ranging and they are associated with the human leukocyte antigen B27 (HLA-B27) genotype, although they can occur in people who are seronegative for HLA-B27.¹⁵ NICE Guideline 65 describes the diagnosis and management of the spondyloarthritis group of diseases.¹³ There is a useful British Medical Journal article¹⁶ that summarises the NICE guideline on the diagnosis and management of spondylarthritis, and an accompanying infographic that provides a visual overview of how to assess people with suspected spondyloarthritis in primary care, and when to refer to a rheumatology specialist.¹⁶

One important feature of axial spondyloarthropathy is inflammatory back pain. Mechanical back pain usually has a definite cause and the patient can remember when it started. Inflammatory back pain has a more insidious onset, with morning stiffness and stiffness after rest. It is relieved by exercise and can cause waking in the second half of the night as the back stiffens up. Inflammatory back pain commonly starts in adults under 35 years of age. If an adult has inflammatory back pain, there is a possibility that they have axial spondyloarthropathy and should be referred to a rheumatology service.¹³

The diagnosis is made on a special magnetic resonance imaging (MRI) scan of the whole spine, using a protocol which outlines bony oedema (short T1 inversion recovery [STIR] and T1 images).¹³ A normal MRI scan will not detect the features of spondyloarthropathy.¹⁶

There are currently long delays in diagnosing axial spondyloarthropathy—sometimes as long as 6 years¹⁷ during which time spinal fusion can occur, with irreparable damage to the spine and loss of mobility. Early diagnosis allows appropriate treatment with physiotherapy and disease-modifying anti-rheumatic drugs.¹³

Enthesitis commonly affects the Achilles tendons and plantar fascia insertions. It can also occur in the elbow causing medial and lateral epicondylitis. Anyone presenting with bilateral enthesitis symptoms should raise the suspicion of an inflammatory spondyloarthritis. A personal or family history of psoriasis is also a diagnostic pointer in patients with recurrent enthesitis; this raises the possibility that the enthesitis is part of an inflammatory process.

8. Know That Gout is the Most Common Cause of Inflammatory Arthritis Worldwide

In UK general practice, the overall prevalence of gout has increased from around 1.4% in 1999 to 2.49% in 2012,¹⁸ despite the availability of effective and potentially curative urate-lowering drugs for more than 50 years and evidence-based British and European management guidelines for nearly a decade.

Untreated gout can cause joint damage and lifelong problems. Gout typically starts in the big toe (first metatarsophalangeal) joint in the middle of the night with acute pain and swelling. The pain is excruciating and not much else can cause such acute pain. The diagnosis is a clinical one, taking into account the presenting features. Serum uric acid levels can be normal in the acute attack and checking at 6 weeks after the attack is recommended.¹⁹ Useful information can also be found in the British Society for Rheumatology guideline for the management of gout.²⁰

9. Remember That the Most Common Cause of Joint Pain is Osteoarthritis

In the UK alone, 8.75 million people have sought treatment for OA.²¹ OA can be diagnosed clinically in anyone over 45 years of age presenting with joint pain which is not due to some other obvious cause. See Box 2 for NICE Clinical Guideline (CG) 177 diagnostic criteria.²²

There may also be features of OA on examining the patient, such as bony joint swelling (osteophytes) and joint deformity (for example, valgus deformity in the knee and Heberden’s nodes in the fingers).

The key to management of OA is patient education and self-management. There are no cures for OA; losing weight and undertaking aerobic and strengthening exercises can all help.²² The University of Keele website lists some useful resources that can be shared with patients.²³

10. Assess the Need for Joint Replacement

Sometimes OA is so severe that joint replacement is necessary. NICE Guideline 157 gives advice on assessing and referring patients who might need joint replacement.²⁴

The principles of the assessment include those for shared decision making:²⁴

‘Support shared decision making by discussing treatment options with people offered primary elective hip, knee or shoulder replacement and their families or carers (as appropriate). Include in the discussions:

• the alternatives to joint replacement
• the potential benefits and risks of the available procedures and types of implant for joint replacement, including the possible need for more surgery in the future
• the options for anaesthesia and analgesia, and the potential benefits and risks of each option (see the section on anaesthesia and analgesia).’

The guideline also recommends preoperative rehabilitation counselling (see Box 3).

Before referring someone for joint replacement, it is useful to try the self-management options described in NICE CG177,²² which include weight loss and exercise. If the patient is at peak fitness and optimum body weight, they are likely to recover with fewer complications from joint replacement.

In previous joint replacement guidelines, use of the Oxford knee and hip scores^25,26 were advised to assess the degree of functional impairment before referral. This advice has been removed from the current guideline and scoring tools are no longer to be used as a method of rationing access to joint replacement surgery.²²

Summary

Adequate assessment of a patient presenting with joint pain is the absolute key to finding the correct diagnosis. A good history will give the clinician many pointers to the cause of the patient’s pain. This article has discussed an approach to obtaining a good history from anyone presenting with joint pain. Recognising when pain might be due to an inflammatory condition will allow prompt referral to a rheumatology service and the timely use of disease-modifying drugs to improve outcomes for the patient. 

Dr Louise Warburton

GP and GPwSI in rheumatology