Approach to joint pain and swelling: Clinical sciences

Joint pain and swelling are common patient concerns that stem from a range of conditions affecting ligamentous, cartilaginous, or bony structures. Based on the underlying cause, joint pain and swelling can occur in combination or separately, and can be associated with traumatic and non-traumatic causes. Moreover, based on the duration of symptoms, non-traumatic conditions can be further subdivided into acute and chronic.

Now, if your patient presents with joint pain and swelling, perform a focused history and physical examination.

Your patient will report joint pain and their physical exam will usually reveal edema, erythema, and warmth over the affected joints, as well as joint line tenderness. Additionally, they might have an effusion, limited range of motion, or associated crepitus. These findings are suggestive of arthralgia or arthritis.

Your next step is to assess for trauma. If your patient presents shortly after an obvious mechanism of injury, such as a motor vehicle collision or sports accident, and has exam signs that suggest trauma, like ligamentous laxity or joint deformity, consider traumatic joint injury, order imaging, primarily an X-ray of the affected joint! Additionally, if you suspect internal derangement of soft tissue, order an MRI! If imaging confirms the presence of a fracture, dislocation, or soft-tissue derangement, diagnose a traumatic joint injury!

On the other hand, if there’s no evidence of joint trauma, assess the duration of symptoms.

If your patient is presenting with acute joint pain, meaning less than 6 weeks, assess the underlying cause!

Here’s a clinical pearl! When approaching a patient with painful joints, consider ordering inflammatory markers, such as ESR and CRP because elevated levels support the diagnosis of underlying infectious and inflammatory causes.

First up is septic arthritis! In this case, history typically reveals fever and malaise, with a possible history of immunosuppression or pre-existing joint disease. The physical exam reveals a monoarticular joint effusion, limited range of motion, erythema, and warmth of the overlying skin. With these findings, consider septic arthritis, so be sure to aspirate synovial fluid for analysis, including the cell count and differential, gram stain, culture, and crystals. If the synovial fluid contains more than 50,000 white blood cells, yields a positive gram stain and culture, appears purulent, and is negative for crystals, diagnose septic arthritis!

Next up is disseminated gonococcal infection. This is usually seen in sexually active individuals who report a fever and rash. The physical exam reveals asymmetric polyarthritis involving the wrists, knees, and ankles. Additionally, you might notice tenosynovitis of the plantar fascia or Achilles tendon, and a pustular rash. With these findings, consider disseminated gonococcal infection and order labs, including nucleic acid amplification testing or NAAT, blood cultures, and synovial fluid analysis. If any of these tests are positive for Neisseria gonorrhoeae, diagnose disseminated gonococcal infection!

Okay, let’s move on to disseminated viral infection! Suppose your patient reports fever, malaise, and possibly a history of known exposure to a viral infection with a physical exam revealing lymphadenopathy and a rash. In this case, consider disseminated viral infection and order serology for hepatitis B and C, HIV, and Parvovirus B19. If any of these serologies are positive, diagnose disseminated viral infection.

Here’s a clinical pearl to keep in mind! Lyme arthritis is an example of a disseminated infection that occurs when the bacteria Borrelia burgdorferi invades the joint space, eventually causing inflammation and pain. Suspect Lyme arthritis in individuals who have traveled to Lyme endemic areas such as the Northeastern, Mid-Atlantic, and upper Mid-Western regions of the United States!

Now let's take a look at rheumatic fever! These patients are usually teenagers or young adults whose joint symptoms were preceded by group A streptococcal infection. The physical exam reveals migratory, asymmetric polyarthritis involving the elbows, wrists, knees, and ankles. Additionally, the physical exam might reveal a new heart murmur or pericardial friction rub, subcutaneous nodules, erythema marginatum, and even choreiform movements known as Sydenham chorea. These findings are suggestive of rheumatic fever, so be sure to assess the Jones criteria, a validated metric used to diagnose rheumatic fever. If your patient meets the criteria, diagnose rheumatic fever.

Finally, let’s discuss crystal arthropathy! These individuals typically report episodic joint pain and swelling, with a possible history of diuretic use, alcohol use, or a high-protein diet. Next, their physical exam reveals erythema, warmth, swelling, and tenderness of the affected joint. In this case, consider crystal arthropathy, so your next step is to order a synovial fluid analysis, including the cell count and differential, gram stain, culture, and crystals. If synovial analysis reveals elevated white blood cells between 2,000 and 50,000, negative gram stain and culture, and the presence of either monosodium urate or calcium pyrophosphate crystals, diagnose crystal arthropathy.

Now, let’s take a look at subacute or chronic joint pain and swelling, which lasts for six or more weeks.

In this case, your first step is to assess for osteoarthritis. Patients with osteoarthritis are typically older in age and report joint pain in one or more joints, such as the knees, hips, and hands that worsens with activity. Additionally, your patient will report morning stiffness lasting less than 30 minutes.

Next, if the physical exam reveals crepitus, limited range of motion, and bony hypertrophy, you should consider osteoarthritis, so be sure to obtain an X-ray of the affected joint.

If the X-ray reveals joint space narrowing, osteophytes, and subchondral sclerosis, diagnose osteoarthritis!

However, if you rule out osteoarthritis, test for autoantibodies, including the antinuclear antibody or ANA and rheumatoid factor or RF for short.

If either ANA or RF are positive, consider systemic rheumatic diseases, primarily rheumatoid arthritis, systemic lupus erythematosus or SLE, systemic sclerosis, and Sjogren syndrome.

Let’s start with rheumatoid arthritis! These patients typically report joint stiffness that lasts more than 30 minutes and occurs either in the morning or with prolonged inactivity. They might also report nonspecific symptoms, such as fatigue and malaise.

The physical exam findings typically include symmetrical swelling and joint tenderness to palpation of the smaller joints. The most commonly affected joints are the proximal interphalangeal and metacarpophalangeal joints or PIP and MCP. You may also find swelling and tenderness of the wrists and metatarsophalangeal or MTP joints.

Moreover, chronic joint inflammation can cause the surrounding structures to shorten, stiffen, and become constricted, which eventually results in contractures. Important contractures to keep in mind include Boutonniere deformities, where there is persistent flexion of proximal interphalangeal joints and hyperextension of the distal interphalangeal or DIP joints; and Swan-neck deformities, where there’s persistent hyperextension of proximal interphalangeal joints and flexion of distal interphalangeal joints.