Adult foot fractures: A guide

MRI/ultrasound in addition to plain films?

Use the Ottawa Ankle and Foot Rules to determine the need for foot radiographs in the acute setting.¹² If indicated, imaging should include AP, lateral, and oblique views of the foot.⁵ Consider magnetic resonance imaging (MRI) if you suspect a stress fracture, which typically presents as an overuse injury in athletes.

Ultrasound may be effective for identifying metatarsal fractures, as well.¹³ Ultrasound can be used to visualize fractures of the long metatarsal bones and identify displacement, angulation, and step-offs. Although its use in the United States has been limited for this purpose, studies in other countries are showing that it yields results comparable to plain films in the emergency department setting for diagnosis and initial management of these fractures.¹³

Differential diagnosis

Multiple other diagnoses present similarly to metatarsal fractures including: ligamentous/tendon/soft tissue injuries, interdigital neuroma, sesamoid fractures, and Lisfranc ligament injury (which we'll discuss in a bit). Stress fractures of the metatarsal, most commonly seen in the second metatarsal, are insidious in nature and are common with repetitive movement such as that made by gymnasts, dancers, and track athletes.¹⁴ Metatarsalgia, which causes pain at the ball of the foot, is a condition that can stem from a myriad of causes including a low or high arch, biomechanics, and previous injury.

Treatment

Nondisplaced, minimally displaced (<3 mm), and minimally angulated (<10° dorsal/plantar angulation) fractures of any metatarsal shaft may be managed conservatively with a hard-soled shoe or walking boot with weight bearing as tolerated for 4 to 6 weeks.¹ Most stress fractures (excluding fifth metatarsal stress fractures) may be treated similarly. Surgical referral is indicated for patients with any open fracture, first metatarsal fractures with displacement, central metatarsal fractures with >10° deformity, >3 mm of translation, multiple fractures, or fifth metatarsal stress fracture.¹

Manage stress fractures and stress reactions of the proximal fifth metatarsal with strict activity modifications and a non-weight bearing short leg cast, given the high risk of nonunion.

Base of fifth metatarsal tuberosity avulsion fractures can be managed nonoperatively with protected weight bearing in a boot or cast for 2 weeks or hard sole shoe for 4 to 8 weeks if the fracture is at the proximal tubercle (see Zone I, FIGURE 2). Jones fractures (Zone II, FIGURE 2) or fractures of the proximal diaphysis (Zone III, FIGURE 2) of the fifth metatarsal may also be managed nonoperatively in patients who are not competitive athletes. This can be done with a non-weight bearing (NWB) short leg cast for 6 to 8 weeks at a minimum.⁴ If the patient is an athlete who wishes to resume competition, surgical referral is indicated, as the risk of nonunion is high with these fractures.¹⁵

Continue to: Stress fractures and stress reactions...