Chapter 277: Foot Injuries

Foot injuries occur most commonly in work and athletic environments.¹ Work-related foot injuries can be associated with substantial medical costs and lost wages.² Sport-related foot and ankle injuries require care so the athlete can return to the demands of the sport as quickly as possible.³ Motor vehicle crash patients with a foot or ankle injury typically have a higher injury severity score than those without such injuries.⁴

ANATOMY

The foot is divided into three sections: the hindfoot, the midfoot, and the forefoot. The Chopart joint separates the hindfoot from the midfoot. The Lisfranc joint divides the midfoot and the forefoot. The hindfoot is comprised of the talus and the calcaneus. The midfoot encompasses the medial, middle, and lateral cuneiforms; the navicular; and the cuboid. The tarsus refers to the bones of the hind and midfoot. The forefoot includes the metatarsals and the proximal, middle, and distal phalanges (Figure 277-1). Ligaments and muscles enable foot movements of eversion, inversion, adduction, and abduction.

Vascular supply of the foot originates from branches of the popliteal artery: the anterior tibial artery, with its branch the dorsalis pedis supplying the dorsal aspect of the foot; and the posterior tibial and peroneal arteries supplying the sole (Figure 277-2).

The sural, saphenous, peroneal, and lateral plantar nerves innervate the foot for both motor and sensory function and originate in branches from the sciatic and femoral nerves.

HISTORY

Ask about the mechanism of injury and direction of force. Obtain key information, including ability to bear weight after the injury, prior injury or surgery to the area, and any other potential injuries. Because it requires great force to fracture the foot, other injuries can coexist, and foot pain can distract from other serious injuries.

PHYSICAL EXAMINATION

The foot examination does not necessarily begin with the foot, but with the entire lower extremity on the affected side. Examine the hip, knee, and ankle. Evaluate neurovascular integrity. Vascular compromise of the foot is identified with diminished pulses, a cool extremity, and mottled skin. Once the general examination is completed and the focused foot examination begins, start with the general appearance of the foot and compare it with the uninjured side. Look for obvious closed or open deformities. Ask the patient to identify painful areas. Palpate the foot for abnormal findings or tenderness. Pay particular attention to the base of the fifth metatarsal and the dorsal aspect of the base of the second metatarsal. Range the joint both passively and actively through all typical motions of the foot. Evaluate gait when possible.

CALCANEUS INJURIES

Clinical Features

The calcaneus is the most commonly fractured tarsal bone, whereas the talus is infrequently fractured.⁵ Fractures in the hindfoot typically require a large force, like an axial load to the heel, to occur. Because of this force, associated injuries are common.

Calcaneal fractures are subdivided into intra-articular and extra-articular fractures, with intra-articular fractures being the more common of the two. A displaced intra-articular fracture is common and poses its own challenges for long-term care. Some surgeons advocate for open reduction and internal fixation; others prefer nonoperative closed reduction; and still others prefer primary arthrodesis.⁶

Diagnosis

Plain radiographs, specifically the lateral view, are needed for fracture diagnosis. The Boehler angle is measured using the lateral view and represents the intersection of two lines: (1) the line drawn from the highest part of the anterior process of the calcaneus and the highest point of the posterior articular surface of this bone, and (2) the line between the highest point of the posterior articular surface of the calcaneus and the most superior part of the calcaneal tuberosity. The normal angle measures between 25 and 40 degrees. When the angle is <25 degrees, suspect a fracture (Figure 277-3). Because this angle varies widely between individuals, a comparison view is helpful if the diagnosis is in question. Although plain radiographs are helpful when the fracture is visible, a CT can provide detail and help clarify the management plan.

Treatment and Follow-Up

For intra-articular fractures, obtain orthopedic consultation to determine the management plan. For nondisplaced fractures, treat an intra-articular fracture with immobilization, a well-padded posterior splint, strict elevation, non–weight-bearing status, and appropriate analgesia. Elevate the leg above the heart to minimize edema and the risk of compartment syndrome (see the chapter titled "Compartment Syndrome"). Displaced fractures may require surgical repair. Care for an extra-articular fracture is elevation, immobilization, analgesia, and orthopedic follow-up. Some of these will require outpatient surgical intervention, with less invasive, percutaneous approaches being adopted in more recent years.⁷

TALUS INJURIES

Clinical Features

Fractures of the talus usually require a significant mechanism such as extreme dorsiflexion or a fall from a great height. "Major" talus fractures are those involving the head, neck, or body of the talus (Figure 277-4) and can result in avascular necrosis. "Minor" talus fractures are those that do not cross the central part of the talus (Figure 277-5). A lateral process talar fracture is sometimes called "snowboarder's ankle," and is commonly mistaken for a lateral ankle sprain.

Diagnosis, Treatment, and Follow-Up

Diagnosis begins with plain radiography, but CT provides better visualization of the talus. Minor talus fractures can be treated on an outpatient basis with a posterior splint, non–weight-bearing status, analgesia, and orthopedic referral. Major talar fractures ideally require orthopedic consultation in the ED.

Dislocations of the talus, when the tibiotalar joint remains intact, are either peritalar or subtalar. The talocalcaneal and talonavicular joints are disrupted by a rotational-inversion force. Dislocations are rare but are orthopedic emergencies. Immediate orthopedic consultation and reduction are necessary to prevent neurovascular compromise to the foot.

LISFRANC INJURIES

Clinical Features

The midfoot is divided into two columns, with the medial column containing the navicular, cuneiforms, and the first three tarsometatarsal joints; the lateral column contains the cuboid and fourth and fifth tarsometatarsal joints (Figure 277-1). The midfoot is a vital bridge between the hindfoot and the forefoot. Injuries to the midfoot have the potential to dramatically affect an individual's daily function, including the ability to stand and walk. Untreated midfoot injuries in diabetics can lead to the development of Charcot's foot (collapse of the mid-foot arch) and lifelong complications with ambulating.⁸

The cornerstone of mechanism, diagnosis, and treatment of Lisfranc injuries lies in the anatomy 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. Its strength exceeds that of the plantar ligament construct by severalfold.⁹ Lisfranc injuries range from sprains to fracture-dislocations, with concurrent fractures of the hind and forefoot being relatively common, especially fractures of the second metatarsal. The usual mechanism of injury for sprains is a low-velocity indirect force, whereas plantar-flexion with an axial load (such as strenuous jumping over an obstacle) is seen in more significant injuries. Sports injuries (specifically football) and motor vehicle crashes are common situations for these injuries.^10,11

Diagnosis

Pain elicited by torsion of the midfoot raises suspicion for a Lisfranc injury. Also, injuries about the tarsometatarsal joint, with pain on passive dorsi- or plantarflexion of the foot, should result in a specific evaluation of the midfoot for a Lisfranc injury. Radiographic studies should include at minimum bilateral weight-bearing anteroposterior (when tolerable), lateral, and 30-degree oblique views of the foot. Bony displacement of 1 mm or greater between the bases of the first and second metatarsals is considered unstable. CT imaging is the ideal imaging study for this injury.¹² It provides better delineation of bony structures and diagnoses occult fractures or subluxations that can be missed on plain radiographs (Figure 277-6).

Lisfranc injuries have multiple classification systems.¹⁰ The Nunley classification groups low-energy ligamentous injuries by diastasis and preservation or loss of arch height: type I are nondisplaced, type II involve diastasis between the first and second metatarsal heads, and type III involve diastasis with loss of arch height.¹¹

Treatment and Follow-Up

Treatment of a nondisplaced injury (<1 mm between the bases of the first and second metatarsals) is with a non–weight-bearing splint, rest, ice, and elevation. Orthopedic reevaluation is usually scheduled within 2 weeks when repeat imaging will likely be obtained and a cast will likely remain on for an additional 4 weeks. At 6 weeks, gradual progressive weight bearing can be attempted.

Displaced Lisfranc injuries are unsTable and require orthopedic consultant in the ED and anatomic reduction.¹³ Whether the reduction is open or closed depends on the degree of the injury and is determined by the orthopedic consultant. Surgical options are variable and range from open reduction and internal fixation to primary arthrodesis.¹⁴ Compartment syndrome is an acute complication of significant Lisfranc injuries (see the chapter titled "Compartment Syndrome").

NAVICULAR INJURIES

Navicular fractures are typically caused by a direct blow or axial loading. Avulsion injuries can also occur with a pulling or rotational force. On physical examination, tenderness and ecchymosis are found about the navicular. Imaging includes bilateral weight-bearing anteroposterior, lateral, and oblique radiographs. CT is best for evaluating the talonavicular joint surfaces. The goals of treatment are maintenance of anatomy and restoration of articular congruity. Nondisplaced fractures should be treated in a non–weight-bearing short leg cast for 6 to 8 weeks, with orthopedic reevaluation in approximately 2 weeks. Orthopedic consultation in the ED is usually required for displaced, and therefore unstable, fractures, to determine the management plan. Given that the central part of the navicular bone is avascular,¹⁵ complications include avascular necrosis, nonunion, and instability, all of which can lead to a flatfoot deformity.

CUBOID INJURIES

The cuboid articulates with the calcaneus and the fourth and fifth metatarsals. Plantarflexion and abduction is the most common mechanism of injury. Imaging includes bilateral weight-bearing anteroposterior, lateral, and oblique radiographs. CT may be helpful. Nondisplaced fractures are treated with a short leg cast and initial non–weight-bearing status. Comminuted injuries are treated with surgery. Complications include foot instability and joint arthrosis.

CUNEIFORM INJURIES

The cuneiforms all articulate with the navicular. Isolated cuneiform injuries are very rare, but especially with a high-energy mechanism of injury, cuneiform fractures can coexist with other fractures of the foot. Imaging studies are the same as for the other bones of the midfoot. Treatment depends on which bone is injured: medial cuneiform injuries are typically treated with surgery, whereas closed reduction usually suffices for the middle and lateral cuneiform bones.

Forefoot injuries cover a broad range from those requiring minimal intervention to those requiring operative repair. Fractures range from the minimally displaced to open, comminuted fractures.

FIFTH METATARSAL INJURIES

Clinical Features

Fractures of the proximal fifth metatarsal occur in three forms and can be identified using the joint between the proximal fourth and fifth metatarsal as a guide: (1) tuberosity or styloid fractures, which are proximal to the joint; (2) Jones fractures, which are also known as metaphyseal-diaphyseal junction fractures; and (3) diaphyseal stress fractures.

Diagnosis

Plain radiographs are usually adequate. CT scans should be considered for more detailed imaging in the high-performance athlete¹⁷ (Figure 277-7).

Treatment and Follow-Up

Patients with nondisplaced Jones fractures should be non–weight bearing in a cast for 6 to 8 weeks. Complications of a Jones fracture treated nonoperatively include bony nonunion, which may later require intramedullary screw fixation. Shock wave therapy has also been reported for treatment of nonunion.¹⁷ Some orthopedic surgeons are advocating for early surgical correction, especially in athletes, so posterior splinting and outpatient referral to an orthopedic surgeon are appropriate initial treatment.¹⁸ Nondisplaced avulsion fractures of the tuberosity, also known as a pseudo-Jones fracture, can be treated with a walking cast and pain control with weight bearing as tolerated.

METATARSAL INJURIES

Proximal fractures of the first through fourth metatarsals are typically caused by a crush injury or direct blow. Take care to exclude an associated Lisfranc injury. An isolated proximal metatarsal fracture can be treated with a posterior splint and non–weight-bearing status. Orthopedic follow-up within 2 to 3 days is needed for the likely placement of a more definitive cast.

Nondisplaced isolated fractures of the shaft of a metatarsal, usually caused by an acute direct blow or twisting force, can typically be seen on oblique or lateral foot films. These can typically be treated with a posterior splint or orthopedic shoe or walking boot (see chapter titled "Initial Evaluation and Management of Orthopedic Injuries"). Repeat imaging can be performed 1 week after injury and then again at 6 weeks. Fractures with displacement of 3 to 4 mm or angulation >10 degrees usually require surgical reduction¹³ (Figure 277-8).

STRESS INJURIES

Chronic direct forces cause stress fractures. Stress fractures typically occur in the setting of increasing activity or chronic overuse and are sometimes called "march fractures." Stress fractures are rarely visible on plain radiographs; MRI can be used when pain is persistent. A clinical diagnosis typically suffices. Cessation of the causative activity usually results in good outcomes for recovery.¹⁸

METATARSOPHALANGEAL INJURIES

Metatarsophalangeal joint injuries are caused by multiple mechanisms and occur in various forms, including sprains, subluxations, and dislocations. Turf toe is a form of a sprain that results when there is acute or chronic hyperdorsiflexion of the first metatarsophalangeal joint while the foot remains in plantarflexion. History usually yields the diagnosis. When radiographs are obtained, a capsular avulsion, the hallmark of this injury, is seen. On physical examination, passive ranging results in a pathologically increased range of motion. Treatment is rest, ice, and elevation. Upon returning to sports, a reinforced shoe can be helpful and protective from further injury.¹⁹ MRI is useful and can diagnose subtle associated injuries.²⁰

Dislocations of the metatarsophalangeal joint, usually dorsal, can also occur. A high-energy mechanism is the usual cause, and this injury often accompanies other foot injuries. Treatment ranges from closed reduction to operative repair, depending on the severity of injury.

PHALANGE INJURIES

Fractures of the phalanges are the most common fractures of the forefoot, with a stubbing mechanism of the hallucal proximal phalanx being the most common injury.¹⁹ Radiographs are obtained if there is extensive injury, suspicion of foreign body or open fracture, or if the great toe is injured. Radiographs are not necessarily obtained for the distal phalanges of the other toes if the only injury is a closed isolated injury of the distal phalanx. Crush mechanisms can lead to distal phalanx fractures. Treatment is with buddy taping to the adjacent toe or application of tape about the forefoot for greater stability (taking care to avoid undue pressure from the tape) and a hard-soled shoe.

For general guidance regarding the care of patients with acute bony foot injuries, see Table 277-1.

Lacerations to the foot may result in injury to the extensor hallucis longus tendon, with inability to dorsiflex the great toe, or tibialis anterior tendon, with loss of dorsiflexion of the foot. Consult with the orthopedist. Treatment is primary repair if the tendon edges are opposable; otherwise, tendon reconstruction is necessary.²¹

Lacerations of the flexor hallucis longus are typically repaired. Lacerations to the flexor tendons of the other toes are generally left unrepaired, as there is little if any functional impact.

Dislocation of the posterior tibial tendon is uncommon and is often misdiagnosed as ankle sprain. Mechanism of injury is forced dorsiflexion of the foot and ankle eversion when the posterior tibial tendon is contracted, as may occur in snowboarding or ice skating.²² Treatment is surgical repair.

Achilles tendon injuries are discussed in the chapters titled "Leg Injuries" and "Soft Tissue Problems of the Foot." Repair of lacerations of the foot is discussed in the chapter titled "Lacerations of the Leg and Foot."

Acknowledgments: The authors would like to thank Drs. John A. Michael, Ian G. Stiell, and Peter Ramsey for their contributions to previous editions of this chapter. We would also like to thank Drs. Esther Choo and Robert DeMayo for the radiographic images.