Monoarticular arthritis presentations in the emergency department are increasing as the population ages and gets heavier. Many etiologies — from trauma to infection to autoimmune-mediated inflammation — are associated with significant disability or early mortality, and their treatments are associated with adverse effects. A systematic approach to evaluating patients with monoarticular arthritic complaints is important for relieving pain, diagnosing systemic illness, and unmasking true arthritis emergencies. Septic arthritis is a rapidly destructive process that can cause significant disability in a matter of hours or days, with relatively high mortality. Other causes of monoarticular arthritis may cause disability in the long term. In all cases, accurate diagnosis and appropriate therapies are crucial for resuming activities and preventing long-term deficits. This review examines the diagnosis and treatment of monoarticular arthritis, with a focus on recent evidence in the diagnosis of septic arthritis and new research on gout therapies. Modalities for pain control and new techniques for imaging are discussed.
A middle-aged man with diabetes and hypertension has been waiting patiently to be seen, with a complaint of right knee pain and swelling that has gradually progressed over several hours. There is no history of trauma, recent or remote, but he describes several gout-like episodes of pain in both feet in recent years, which improved with rest and NSAIDs. He was triaged as an ESI4, and the waiting room is packed. Fortunately, the charge nurse comments on how uncomfortable he looks and he is brought into the ED for evaluation. The patient is afebrile, but the knee is hot, beefy red, and swollen. The ED is over-capacity and the patient’s history is reassuring, so you consider keeping him in a chair. But that knee looks impressive and you wonder if your plan is aggressive enough.
Just then, your nurse brings a new patient back to the adjacent room. He is loudly complaining of shoulder pain, a flare-up resulting from a shoulder injury years before. He is 40 and has no other medical problems. “My pain doc usually just gives me a shot, but he’s out of town,” he said. You order a film and 800 mg PO ibuprofen, but you wonder if an intra-articular injection of analgesia and steroids would be better.
Arthritis is the most common cause of disability in the United States,1 and this is likely to increase as the population gets older and heavier. Because of the limitations in activity that are associated with joint inflammation, patients with arthritis complaints frequently present to the emergency department (ED).2
Monoarticular arthritis, in particular, represents a diagnostic dilemma. Presentations run the gamut from exacerbations of chronic osteoarthritis (OA) that has been developing for years to rapidly progressive infectious arthritides that can quickly disable or kill in days. Identifying and promptly treating septic arthritis, a true medical emergency, remains the cornerstone of the workup for monoarticular arthritis. Both inside and outside of emergency medicine, misconceptions in the diagnosis of septic arthritis persist. New evidence about the limited role of examination, imaging, and blood testing, as well as the importance of arthrocentesis, are covered in this review.
Beyond septic arthritis, other causes of monoarticular arthritis can still be painful and debilitating. New data and guidelines for therapy related to the diagnosis and treatment of gout, pseudogout, and OA are reviewed as well as diseases that can occasionally present as monoarticular arthritis, such as Lyme disease and reactive arthritis.
Recent years have seen renewed interest in emergency arthritis presentations and management, particularly surrounding diagnosis of septic arthritis and treatment of gout. There are also new guidelines from The European League Against Rheumatism (EULAR), the American College of Radiology (ACR), and the American Academy of Orthopedic Surgeons (AAOS) as well as Cochrane Library of Systematic Reviews concerning arthritis management. These guidelines have emphasized evidence-based recommendations, when possible, although the priority is often on long-term management, and definitions of “acute” and “short-term” may seem unusual to emergency clinicians.
Ovid MEDLINE® was queried for clinical trials since 2004 that matched emergency and arthritis. The website www.guidelines.gov was also queried using similar search terms over that period. The Cochrane Database of Systematic Reviews was surveyed for applicable systematic reviews. Finally, the recent orthopedics and rheumatology literature was searched regarding new therapies for gout and other monoarticular arthritides.
There is no serum blood test that can rule out septic arthritis.
While there is a theoretical risk that aspirating through cellulitis may inoculate a sterile joint with bacteria, there is a more concrete, measurable risk in skipping arthrocentesis and prompt management in a septic joint. Try the tap, through cellulitic-looking tissue, if necessary.
Elderly patients may not present with an impressive examination, but they are still at risk for septic arthritis, especially if they’re immunocompromised (eg, on steroids for COPD) or if they have a history of RA.
Nonpharmacologic therapy such as orthotic shoes, canes, splints, and immobilizers have been shown to help in OA – so does specialty follow-up. Try it.
Gout goes hand in hand with renal insufficiency – and other therapies are less nephrotoxic. Investigate further or try another therapy before writing a script for NSAIDs.
Gonococcal arthritis is managed nonoperatively, and HIV can cause arthritis in several ways that won’t resolve at the time of hospital discharge. Investigate further.
In gouty flares, temporarily withholding thiazide diuretics and abstaining from alcohol and purine-rich foods will probably help decrease the duration and intensity of symptoms.
Septic arthritis can coexist with gout or pseudogout – sending Gram stain and culture can save the joint and the patient.
Patients with Lyme arthritis may not recall a tick bite or may not have experienced erythema migrans. Treat based on exposure and clinical presentation.
Bursitis and tendonitis can look like septic arthritis – but in septic arthritis, the joint should hurt with any active or passive ranging. Ask about minor trauma and repetitive stress.
Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.
To help the reader judge the strength of each reference, pertinent information about the study will be included in bold type following the reference, where available. In addition, the most informative references cited in this paper, as determined by the authors, are noted by an asterisk (*) next to the number of the reference.
Nicholas Genes; Makini Chisolm-Straker
May 2, 2012