Foot Injuries in the Emergency Department

Foot Injuries in the Emergency Department

By Ahmed Alrasheedi MBBS, MPH
(EM Resident Physician, University of Maryland Medical Center)

Edited by Alex Koyfman MD (@EMHighAK) and Stephen Alerhand MD (@SAlerhand)

The foot is divided into three regions:

  • Hindfoot: Contains talus and calcaneus.
  • Midfoot: Contains navicular, cuboid, and cuneiform bones.
  • Forefoot: Contains the metatarsals, phalanges, and sesamoids.

The midtarsal joints (Chopart’s joint) join the hindfoot and midfoot.
The tarsometatarsal joints (Lisfranc’s joint) join the midfoot and forefoot.

foot anatomy
From Rockwood CA, et al [eds]: Rockwood and Green’s Fractures in Adults, 3rd ed. New York, JB Lippincott, 1991

 

Hindfoot

Case 1:
29 yo involved in MVC c/o ankle pain and inability to bear weight.

talus fracture

Talus Injuries:
  • Blood supply runs through the neck and the posterior part of the talus, forming an anastomosis in the middle. Disruption will put the talus at risk of AVN.
  • Major talus fractures are those involving the neck or body of the talus, which can result in avascular necrosis. Require large amount of force.
  • Minor talus fractures involving lateral process are sometimes called “snowboarder’s ankle,” and are commonly mistaken for a lateral ankle sprain.
  • Posterior process fracture can mimic ankle sprain.

talus injury

Pearls and Pitfalls:

  • Talus neck fracture is at high risk of AVN.
  • Posterior and lateral process fractures can be subtle and mimic ankle sprain!
  • Talar dome fracture can be subtle and can often be misdiagnosed as an ankle sprain!

Management:

  • Major talar fractures require precise open reduction and internal fixation.
  • Many minor talar fractures heal with casting, and the initial treatment should be with a non-weight-bearing below-knee cast or posterior plaster slab.
  • Other minor fractures, such as displaced lateral process fractures, require operative fixation because of their articular involvement.

Case 2:
22 yo jumps off a 30-foot tower and lands on his feet c/o heel pain.

calcaneus injury                                     

Calcaneus Injuries:
  • Frequently mistaken for ankle sprain because of “negative” x-ray.
  • At a teaching hospital ED, the “miss rate” was 3rd greatest for calcaneal fractures at 10%.
  • Look for heel tenderness and subtle x-ray findings.

Bohler’s Angle:

  • Normal between 25 and 40 degrees.
  • If angle is <25 degrees, suspect a fracture.
  • Comparison view is helpful if the diagnosis is in question.

Bohler's angleBohler's angle II

Management:

  • Orthopedics should be consulted in the ED for intra-articular and displaced
  • Beware of spine injuries and compartment syndrome of the foot.
  • Leg elevation will minimize edema and the risk of compartment syndrome.

Pearls and Pitfalls:

Foot injuries that can mimic ankle sprain:

  • Snowboarder’s fracture (lateral process of talus)
  • Posterior talus process fracture (Shepherd’s fracture)
  • Achilles tendon rupture
  • Anterior process calcaneus fracture
  • Talar dome fracture

talus lateral process fracture

Talus lateral process fracture: “snowboarder’s ankle”

talus posterior process fracture
Talus posterior process fracture (Shepherd’s fracture)

anterior process calcaneal fracture
Anterior process calcaneus fracture

talar dome fracture
Talar dome fracture

If in doubt, place a splint, make it non-weight bearing, and discharge with orthopedic follow-up.

 

Midfoot

Case 3:
52 yo diabetic c/o foot pain after stepping in a hole.

Lisfranc fractureLisfranc fracture II

Lisfranc fracture:
  • The cornerstone of Lisfranc injuries lies in the disruption of the second metatarsal and the Lisfranc ligament, which runs between the lateral base of the medial cuneiform and the medial base of the second metatarsal.
  • Bruising in the plantar aspect of the midfoot, described as the plantar ecchymosis sign, is helpful in recognizing subtle Lisfranc injuries.

Pearls and Pitfalls:

  • Pain elicited by torsion of the midfoot raises suspicion of a Lisfranc injury.
  • High index of suspicion is exercised in patients complaining of midfoot pain.
  • 1 mm or greater between the bases of the first and second metatarsals on foot x-ray is considered unstable.

Lisfranc fracture III Lisfranc fracture IV

Figure 1                             Figure 2

Fig. 1:  (Lateral view) The superior borders of the medial cuneiform and the base of the 1st metatarsal align.

Fig. 2: (AP View) No diastasis of more than 2mm. Also one can see that the lateral border of the 1st Metatarsal is aligned with the lateral border of the medial cuneiform bone. The medial border of the second metatarsal is aligned with the medial border of the middle cuneiform bone. This is good alignment and indicates the Lisfranc ligament extending from the base of the second metatarsal to the medial cuneiform is intact.

(Source: http://emrems.com/tag/foot/)

Management:

  • Non-displaced injury (<1 mm between the bases of the first and second metatarsals) is with a non–weight-bearing splint, rest, ice, and elevation.
  • Orthopedic re-evaluation at 2 weeks and gradual progressive weight bearing can be attempted after 6 weeks.
  • Displaced Lisfranc injuries are unstable and require orthopedic consultant in the ED.
  • Beware of compartment syndrome in significant Lisfranc injuries!


Forefoot

Case 4:
25 yo female with inversion injury to right ankle. Tenderness over the 5th metacarpal bone.

Jones fracture

Jones fracture:
  • First described by an orthopedic surgeon, Robert Jones. He sustained the injury and subsequently published his experience. Descriptions of this fracture in the literature are often confusing.

Pearls and Pitfalls:

  • Jones fractures do not result from a simple avulsion injury.
  • Clarification: A Jones fracture is a transverse fracture that lies distal to the styloid process of the fifth metatarsal, i.e. distal to the articulation between the bases of the 4th and 5th metatarsals. Characteristically it is positioned within 1.5 cm of the tuberosity.
5th metatarsal bone fracture:
  • Tuberosity or styloid fractures (Pseudo-Jones): Treated with walking cast and analgesia. Weight bearing as tolerated.
  • Jones fractures: Treated with 6-8 weeks of non-weight bearing cast for non-displaced At risk of nonunion. Displaced fractures need operative management.

Jones fracture II

Case 5:
45 yo male sustained direct trauma to his right foot.

Tarsometatarsal joints

Injury to the tarsometatarsal joints:
  • Walking and weight-bearing depend on the accurate alignment of the tarsometatarsal joints.
  • Traumatic subluxations at the bases of the metatarsals (i.e. Lisfranc injuries) will be overlooked unless the normal alignment of the bones is carefully assessed.

Lisfranc subluxation

Lisfranc subluxation: fracture near the base of the 2nd metatarsal has freed the shaft of this bone from the restraining cuneiform mortise. Lateral slippage of the metatarsal bases has occurred in this patient.

Pearls and Pitfalls:
  • Beware of tiny flakes of bone avulsed from the base of the 2nd or 3rd metatarsal. A tiny flake is a big warning!
  • An injury to a Lisfranc joint is a clinical possibility even with a normal x-ray. Remember that the x-rays are obtained as non-weight-bearing images and the joint is not under the stress that occurs when the patient is standing.
  • Even a very slight subluxation requires reduction/management in order to preserve or restore function.

 

Case 6:
37 yo c/o foot pain over the 3rd metatarsal bone. He started training for a half marathon two weeks ago.

stress fracture

Stress Fractures:
  • Fracture results from stress of weight bearing after prolonged walking.
  • Runners stress fracture occurs most often in metatarsal neck, while in dancers, stress fractures usually occur in proximal shaft.
Pearls and Pitfalls:
  • These injuries are frequently missed, misdiagnosed, mistreated, and misunderstood.
  • The 2nd and 3rd metatarsals are most commonly affected. Patient usually endorses an increase in physical activity with no clear history of preceding trauma. On examination, tenderness is at the middle of the shaft of the third metatarsal. The pain is worse with ambulation and flexion or extension of the toes and subsides with rest.
  • X-ray abnormalities may not be visible for two or more weeks after the onset of symptoms.
  • Treatment is symptomatic with relative rest. Patients may benefit from a walking boot or crutches if the pain is severe.

stress fracture II

Four radiographic patterns may be present: (a) Normal; (b) Transverse or oblique crack (3rd metatarsal); (c) Faint periosteal reaction or fluffy callus (3rd metatarsal); and (d) Profuse callus (3rd metatarsal)

Source (Accident and Emergency Radiology: A Survival Guide, 3rd ed., 2015)

 

References // Further Reading

– Wheeless CR. Wheeless’ Textbook of Orthopaedics (web-based resource at http://wheeless.orthoweb.be/), 1996.
– Freed HA, Shields NN. “Most Frequently Overlooked Radiographically Apparent Fractures in a Teaching Hospital Emergency Department.”Ann Emerg Med, Oct 1984; 13: 900-904.
– Accident and Emergency Radiology: A Survival Guide textbook, chapter 7, 3rd ed., 2015
– Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, foot and ankle injury 8th edition
– CURRENT Diagnosis & Treatment Emergency Medicine, 7e.
– Perron AD, Brady WJ. Evaluation and management of the high-risk orthopedic emergency. Emerg Med Clin North Am. 2003 Feb;21(1):159-204.
– Martin Gunn. Pearls and Pitfalls in Emergency Radiology: Variants and Other Difficult Diagnoses, May 2013.
– Simon’s Emergency Orthopedics, Chapter 23, Foot injuries.
http://www.ncbi.nlm.nih.gov/pubmed/24342871
- http://www.ncbi.nlm.nih.gov/pubmed/25269589
- http://www.ncbi.nlm.nih.gov/pubmed/22981663

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