WIDI - M4) Foot pain after a fall from a horse

M4) Foot pain after a fall from a horse

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 foot pain.
Review the DDx considerations in a patient with foot pain.
Identify the spectrum of imaging findings in appropriate modalities for evaluating a patient with foot pain.

History

A 33-year-old female is brought to the ED by their spouse for right foot pain after a fall from horseback. She lost balance and fell off her horse with her right foot remaining fixed in the stirrup, abruptly halting her fall. She denies any head strike or loss of consciousness. She reports exquisite pain over the right mid-foot worse with attempted ambulation and any movement of the right foot and ankle.

Physical Exam

BP: 139/88 HR 90 RR 16, Temp 37C, O2 saturation 100%. Extremities: Tenderness to palpation and swelling to the right midfoot. Exquisite pain reproducible with pronation and abduction of right foot. Medial plantar ecchymosis. The patient is unable to bear weight on right foot.

Labs

None

Provisional Diagnosis

Select the Dx you believe is most appropriate

Ankle fracture

Lisfranc injury

Stress fracture

Calcaneal fracture

Considering the mechanism of injury (fall from horse with foot in stirrup) and presentation (right mid-foot pain reproducible with pronation and abduction of right foot, plantar ecchymosis, and inability to bear weight), the patient most likely has a Lisfranc injury.

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

The patient requires routine, but expedited, workup.

First Imaging Study

What is the first imaging study you will order?

X-ray right foot

CT right foot

MRI right foot

Three-view X-rays of the right foot is the best initial imaging modality to evaluate for bony abnormalities.

View ACR Appropriateness Criteria

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Pertinent Imaging Observations

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

X-Ray 3-view right foot

There is appropriate alignment between each of the tarsal-metatarsal joints.

Yes

There is widening of the space between the first and second metatarsal bases and the medial and intermediate cuneiforms.

There is a metatarsal fracture.

Yes

There is an oblique fracture at the right second metatarsal base.

View Report

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

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Second Imaging Study

What is the next imaging study you will order?

CT right foot

None

The diagnosis is confirmed with the radiographs. Sometimes MRIs are obtained to evaluate the extent of the ligamentous injury.

Well done. You were correct

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

Metatarsal fracture of right foot

Fracture-dislocation of tarsometatarsal joint of right foot

Lateral cuneiform fracture

Bimalleolar fracture

Both A and B

The patient has an oblique fracture to the right second metatarsal with widening of the space between the first and second metatarsal bases and the medial and intermediate cuneiforms, which is concerning for tarsometatarsal joint dislocation (Lisfranc injury).

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

The patient will require routine, but expedited, workup and management.

Assessment and Plan

Please provide your assessment and plan for this patient

This patient is a 33-year-old female presenting with a right foot Lisfranc injury. We will consult orthopedic surgery as she will likely require operative intervention.

Lessons Learned:
- The Lisfranc ligament attaches the medial cuneiform to the base of the 2nd metatarsal on the plantar aspect of the mid-foot.
- The tarsometatarsal (TMT) joint complex forms an arch that provides stability to the midfoot. The 2nd tarsometatarsal joint acts like a keystone in this arch.
- A Lisfranc injury is a complex injury involving the TMT joint complex.
- Pain to the midfoot with pronation and abduction, as well as plantar ecchymosis, should increase suspicion for Lisfranc injury.
- The first best diagnostic modality is a three views X-ray of the foot. Fractures to the tarsometatarsal joint complex increase the likelihood that the patient will require surgery.
- In cases where radiographs are normal or equivocal, but a Lisfranc injury is still suspected, an CT or MRI of the foot should be ordered.

Socioeconomic Factors:
- Bony and ligamentous injury to the foot may require surgery and significant time away from work. A meta-analysis of the socioeconomic impact of orthopedic trauma suggests that of 13% of fracture patients may lose employment because of injury.
- Patients with Lisfranc injury who underwent operative intervention may require up to a year before returning to their level of prior level of activity. Some patients are unable to return to their full level of activity.

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