WIDI - M10) Recurrent foot pain

M10) Recurrent foot pain

Review the Learning Outcomes, Hx, PE and Labs, and begin the module with your Provisional Diagnosis. Keep hitting "Next" to move through the module.

Learning Outcomes

Articulate your relationship with the consulting diagnostic radiologists in the evaluation of a patient with joint pain.
Review the DDx considerations in a patient with joint pain.
Identify the spectrum of imaging findings in appropriate modalities for evaluating patients with joint pain.

History

A 45-year-old male presents to the clinic due to severe pain in the left first metatarsophalangeal (MTP) joint. The pain started and was most severe last night after going to a barbecue where he ate hamburgers, steak, and had alcoholic drinks. This occurred a few months ago, but resolved on its own. The patient takes has a history of congestive heart failure for which he takes furosemide.

Physical Exam

BP: 122/80, HR 84, RR 15, Temp 98.6, O2 saturation 99%. MSK: left first MTP joint warm, erythematous, and severely tender to palpation with excruciating pain on passive range of motion.

Labs

BMI: 34 WBC: 7.0 x 109/L (nl: 4.5-11.0 x 109/L) Uric acid: 30 mg/dL (nl 3.5-7.2mg/dL)

Provisional Diagnosis

Select the Dx you believe is most appropriate

Septic arthritis

Rheumatoid arthritis

Osteoarthritis

Gout

This patient with obesity, an elevated uric acid level, and loop diuretic use is most likely presenting with podagra, or acute gout flare of the big toe. This was likely provoked by the intake of red meat and alcohol the day prior. Septic arthritis is less likely considering the normal WBC count. Inflammatory (rheumatoid) arthritis and osteoarthritis are less likely considering the acuity.

Well done. You were correct

Potential Acuity

What is your assessment of the likely acuity for this patient?

Emergent (immediate plan required)

Urgent (plan required within 4 hours)

Routine

Well done. You were correct

As the patient’s condition is not life or limb threatening, they require routine, but expedited workup.

First Imaging Study

What is the first imaging study you will order?

Foot X-ray

Foot CT

Foot MRI

A foot X-ray is a relatively inexpensive initial test to evaluate for the presence crystalline arthritis.

View ACR Appropriateness Criteria

Well done. You were correct

Pertinent Imaging Observations

Click on the links below to view images from the study, and assess these key findings as best you can.

Foot X-ray

There is soft tissue swelling.

Yes

There is soft tissue swelling adjacent to the medial great toe.

The soft tissues are otherwise normal.

Yes

There is a tophus in the medial margin of the TMT joint.

The cortex of the bone is normal.

Yes

There are corticate erosive changes in the flexor sesamoids, cuneonavicular joints, fourth, and fifth TMT joints.

View Report

Watch our video

View the full study if you'd like to take a look yourself.

Launch Dicom

Second Imaging Study

What is the next imaging study you will order?

Foot CT

Foot MRI

None

No further imaging is required as the diagnosis is strongly suspected with the X-ray.

Well done. You were correct

What is your Diagnosis now that you have seen the imaging results?

Inflammatory arthritis

Crystalline arthritis

Erosive osteoarthritis

This patient is most likely presenting with gout, or crystalline arthritis.

Current Acuity

Initially, you selected and we suggested acuity.

Has your concern for this patient changed?

Emergent (immediate plan required)

Urgent (plan required within 4 hours)

Routine

As the patient’s condition is not life or limb threatening, they require routine, but expedited workup.

Assessment and Plan

Please provide your assessment and plan for this patient

This is a 45-year-old male presenting with gout of the left foot. Diagnosis should be confirmed with arthrocentesis, which would demonstrate negatively birefringent crystals and cloudy synovial fluid with leukocytosis (no greater than 50,000, which would suggest septic arthritis). NSAID and colchicine should be administered for pain control. The patient should also be started on allopurinol to prevent future recurrence. He should also undergo counseling to avoid triggers such as meat and alcohol.

Lessons Learned:
- Gout presents as extreme, sudden onset joint pain and swelling. It often affects the foot and knee. Food, medications, or conditions leading to increases in purine levels can lead to an acute episode. Medications that are nephrotoxic or lower urate can also lead to gout flares.
- The gold standard diagnostic technique for gout is an arthrocentesis which demonstrates negatively birefringent monosodium urate crystals.
- If an X-ray is obtained, a joint effusion can be evident in the acute stage. Chronic findings include erosive, lytic lesions with adjacent tophi.

Socioeconomic Factors:
- Overall, gout appears to be more prevalent in Black and Asian adults. Risk factors for gout, including low educational level, poverty, high BMI, and poor diet quality, were shown to be higher in black compared to white adults. While Asians were found to be more likely to seek ambulatory care for gout, they were less likely to receive allopurinol.
- The associations between poverty and gout as well as BMI and gout were more significant in women compared to men.
- A diagnosis of gout can be made based on clinical examination and joint aspiration alone, without the need for imaging.

That's the end of the module! Once you've reviewed the video(s), you can click here for another case challenge.