Calcaneus and Other Tarsal Fractures




Fractures of the tarsal bones are relatively uncommon. The calcaneus is the tarsal bone most often fractured, representing 60% of all tarsal fractures. The talus is the second most frequently fractured tarsal bone. Despite advances in the treatment of fractures over the years, the common calcaneal fractures still have a poor prognosis in regard to time lost from work and recreation. Isolated fractures of the tarsal bones of the midfoot—the navicular, cuboid, and cuneiform bones—are unusual. Typically, midfoot injuries involve multiple fractures or fracture dislocations. Calcaneus fractures in children are usually nondisplaced but are difficult to detect on plain radiographs.


See Appendix for stepwise instructions for weight-bearing and non–weight-bearing short-leg casts and a lower extremity splint used in the treatment of calcaneus and other tarsal fractures.


Go to Expert Consult for the electronic version of a patient instruction sheet named “Broken Foot or Ankle,” which covers the steps of care from pain relief to rehabilitation exercises. This can be copied to hand out to patients to assist them during the treatment period.


Calcaneus Fractures (Adult)


Calcaneal fractures are generally subdivided into intraarticular and extraarticular fractures. Approximately one third are extraarticular, and compared with those with an intraarticular fracture, those who sustain an extraarticular fracture are typically younger, and the incidence of bilateral fractures is lower. These differences relate to the different mechanisms of injury. Extraarticular fractures result from deforming forces, and intraarticular fractures result from high-energy accidents. Fractures of the anterior process and the tuberosity are the most common types of extraarticular fractures. Controversy exists in the treatment of calcaneal fractures in general but less so in the management of extraarticular fractures compared with the intraarticular type.


Anatomic Considerations


The foot is divided into the hindfoot (calcaneus and talus), midfoot (navicular, cuboid, and cuneiforms), and forefoot (metatarsals and phalanges) ( Figure 14-1 ). The calcaneus is the largest of the tarsal bones. It provides support for the weight of the body and functions as a springboard for locomotion. The calcaneus has only a thin cortical shell, which makes it susceptible to fracture.




FIGURE 14-1


Hindfoot, midfoot, and forefoot divisions of the bones of the foot.


Figure 14-2 demonstrates the important anatomic relationships of the calcaneus. Superiorly, the calcaneus articulates with the talus through three facets that form the subtalar joint. Anteriorly, the calcaneus articulates with the cuboid bone. On the plantar surface are medial and lateral processes that serve as the insertion points for the plantar fascia and muscles. The medial surface has a projection known as the sustentaculum tali. The Achilles tendon inserts into the superior aspect of the calcaneal tuberosity, the hindmost portion of the bone.








FIGURE 14-2


Lateral ( A ), medial ( B ), and plantar ( C ) views of the bones of the foot.


The bifurcate ligament connects the anterior process of the calcaneus to both the cuboid and navicular bones. This ligament is stretched with inversion stress similar to a lateral ankle sprain mechanism.


Imaging


The initial radiographic series for any patient who complains of hindfoot pain after an injury consists of three views: lateral, axial, and dorsoplantar ( Figure 14-3 ). Most calcaneal fractures can be seen on at least one of these views. CT is indicated if a fracture is likely but plain films are normal and for fractures through the body of the calcaneus to rule out intraarticular extension. Because calcaneal fractures can be bilateral, obtaining radiographs of both feet should be strongly considered. Even if no fracture has occurred on the other side, comparison views are especially helpful in the measurement of normal anatomic angles. Views of the lumbar spine and ipsilateral ankle should be obtained when a patient has a calcaneus fracture because of the likelihood of associated fractures in these areas.




FIGURE 14-3


Standard calcaneus radiographic series. A, Lateral view. B, Axial view. C, Dorsoplantar view. The axial view is obtained by directing the beam obliquely through the heel from the plantar surface while the ankle is held fully dorsiflexed.


The normal alignment of the calcaneus in relation to the talus can be assessed on a lateral view by looking for the preservation of two angles ( Figure 14-4 ). Bohler’s angle is measured by drawing a line from the highest point of the posterior aspect of the calcaneus to its highest midpoint. A second line is drawn from this point to the highest point of the anterior process. This angle normally measures between 20 and 40 degrees and is usually similar in the two calcanei of one individual. If the angle is less than 20 degrees, a depressed fracture is present. The apex of the lateral process of the talus (LPT) points directly at the crucial angle, also known as the crucial angle of Gissane. Driven by compressive forces, the talus acts as a wedge to disrupt the subtalar joint and distort the crucial angle.




FIGURE 14-4


Lateral view of the calcaneus demonstrating Bohler’s angle and the crucial angle of Gissane. The normal Bohler’s angle is 20 to 40 degrees.


Classification


The primary function of a classification scheme for calcaneal fractures is to distinguish those with a good prognosis (the extraarticular fractures outside the subtalar joint) from those that require more aggressive treatment and do poorly (the intraarticular fractures involving the subtalar joint). The extraarticular fractures include fractures of the anterior process, the medial or lateral process, the tuberosity, the sustentaculum tali, and the body not involving the subtalar joint. The intraarticular fractures are more common and are difficult to subclassify because of the wide variety of patterns with varying degrees of displacement that can be present. Patients with intraarticular fractures should be referred to an orthopedic surgeon early because the specialist’s knowledge and experience with these basic patterns are essential in developing a reasonable treatment program.


Extraarticular Fracture: Anterior Process


Mechanism of Injury


The anteriormost portion of the calcaneus may be fractured in two ways. An avulsion fracture caused by adduction and plantarflexion of the foot resulting in a pull-off of the attached bifurcate ligament is the most common type. A compression fracture of the anterior calcaneal articular surface occurs infrequently and is caused by forceful abduction of the forefoot with compression of the calcaneocuboid joint with the heel fixed to the ground. Treatment of these two anterior process fractures varies, so distinguishing them is important.


Clinical Presentation


Patients with an anterior process fracture usually report a twisting injury of the foot and complain of pain and swelling just distal to the lateral malleolus. Noting the point of maximal tenderness, which is typically over the calcanealcuboid joint (~1 cm inferior and 3 to 4 cm anterior to the lateral malleolus), can help the clinician distinguish an anterior avulsion fracture from a lateral ankle sprain. This point can be best located by placing a thumb on the lateral malleolus and the third digit on the base of the fifth metatarsal with the index finger pointing out the tender area.


Imaging


The lateral oblique view of the calcaneus is the best projection for visualizing the anterior calcaneal process avulsion fracture ( Figure 14-5 ). This view is taken with the inner border of the foot placed on the film and the sole inclined 45 degrees. Compression fractures of the anterior process can be seen on the lateral view of the foot. Avulsion fractures of the anterior process are usually small and nondisplaced and do not involve the calcaneocuboid joint ( Figure 14-6 ). Anterior compression fractures are usually larger and involve the cuboid articulation. Some patients have a small accessory bone just adjacent to the anterior process. The accessory ossicle can be distinguished from an avulsion fracture by its smooth, rounded contour, which differs from an irregular fracture surface.




FIGURE 14-5


Left, Lateral oblique view of the calcaneus. The x-ray beam is centered 1 inch below and 1 inch anterior to the lateral malleolus. Right, The anterior process is well visualized on this view ( arrow ).



FIGURE 14-6


Lateral view of the calcaneus, demonstrating a small nondisplaced avulsion fracture of the anterior process ( large arrow ). A nondisplaced fracture of the cuboid is also present ( small arrow ).


Indications for Orthopedic Referral


Patients with large or displaced fractures of the anterior process should be referred for proper reduction and fixation. Persistent pain and nonunion are potential late complications, so some of these patients may benefit from surgical excision of the fracture fragment.


Initial Treatment


Table 14-1 summarizes management guidelines for extraarticular fractures of the calcaneus.



Table 14-1

Management Guidelines for Extraarticular Calcaneus Fractures





































































Initial Treatment
Splint type and position Body compression dressing
Initial follow-up visit Within 7 days for definitive casting
Patient instruction Non–weight bearing for 48 to 72 hours
Icing and elevation are important to reduce swelling
Active ROM of the foot and ankle as soon as pain permits
Follow-up Care
Cast or splint type and position Anterior or medial or lateral process: SLWC
Tuberosity: SLNWBC, 5 to 10 degrees equinus
Sustentaculum tali: SLNWBC
Body: no immobilization, active exercise
Length of immobilization Anterior or medial or lateral process: 4 weeks
Tuberosity: 6 weeks
Sustentaculum tali: 6 to 8 weeks
Healing time 6 to 12 weeks for complete return of function
Possible pain and stiffness for months
Follow-up visit interval Every 2 to 4 weeks
Repeat radiography interval For all fractures, after immobilization discontinued
1 week after casting of tuberosity fracture to check for alignment
Considered for delayed clinical healing
Patient instruction ROM and strengthening exercises of the foot and ankle after immobilization
Achilles tendon stretching is important to regain function
Physical therapy should be considered if more aggressive rehabilitation is needed
Heel padding as required for discomfort
Indications for orthopedic consult Displaced fractures
Persistent pain
Nonunion

ROM, range of motion; SLNWBC, short-leg non–weight-bearing cast; SLWC, short-leg walking cast.


The initial treatment of all extraarticular fractures consists of rest, elevation, icing, and a bulky compression dressing for the first 48 to 72 hours to minimize swelling. Patients should remain non–weight bearing until definitive casting has taken place. To prevent joint stiffness, active range of motion (ROM) exercises for the foot and ankle should be started as soon as tolerated.


Follow-up Care


Patients should be seen within the first week after the injury for casting. Nondisplaced fractures of the anterior process heal well with immobilization in a short-leg walking cast for 4 weeks. Patients may have pain or stiffness for several months after treatment. Ankle and foot flexibility exercises should be emphasized after discontinuation of cast immobilization. Physical therapy should be considered for patients who are unable to comply with home therapy or who need assistance with rehabilitation.


Return to Work or Sports


The period of immobilization is relatively short compared with the total time required to return to a full preinjury activity level. Diligent effort during the rehabilitation period should help patients resume more physically demanding activities sooner. Those in more sedentary jobs should be able to work throughout the period of immobilization and rehabilitation. Return to activities that put the patient at risk of reinjury should be avoided for 3 to 4 weeks after immobilization is discontinued.


Extraarticular Fracture: Medial or Lateral Process


Mechanism of Injury


Medial or lateral calcaneal process fractures rarely occur. When they do, the usual cause of injury is a fall on the heel, typically from some height, while the ankle is in eversion (medial) or inversion (lateral).


Clinical Presentation


After this injury, patients complain of pain, swelling, and tenderness localized over the posteromedial or posterolateral heel. Pain may occur with forced dorsiflexion of the ankle; otherwise, joint ROM is normal.


Imaging


The axial calcaneal view is best for delineating fractures of the medial or lateral process. These fractures are rarely displaced but may on occasion be comminuted.


Indications for Orthopedic Referral


Displaced fractures can usually be reduced adequately with closed manipulation. After appropriate sedation/anesthesia, medial or lateral compression of the heel with the palms of the hand should produce the desired alignment. If closed reduction fails, the patient should be referred for consideration of open reduction and internal fixation (ORIF).


Follow-up Care


Use of a well-molded short-leg walking cast for 4 weeks provides protection until the fracture fragments unite. A radiograph should be obtained after this period of immobilization to document fracture union. The heel may remain tender for several weeks, and this symptom is best managed with partial weight bearing as tolerated and heel padding. Infrequently, a patient with this fracture has persistent tenderness over the fracture site. This late complication is best treated conservatively. Malunion and nonunion are uncommon.


Return to Work or Sports


Patients may have difficulty getting back to full weight-bearing or weight-loading activity for several weeks after cast immobilization because of residual heel soreness. A gradual return to activity is advisable. Modification of shoe wear with padding or orthotics may allow an earlier return to more physically demanding activity. Those in more sedentary jobs should be able to work throughout the period of immobilization and rehabilitation. Return to activities that put the patient at risk of reinjury should be avoided for 3 to 4 weeks after immobilization is discontinued.


Extraarticular Fracture: Tuberosity


Mechanism of Injury


Fractures of the tuberosity result mainly from a fall from height or striking the heel on a ledge. Most of these fractures occur from an avulsion force caused by contraction of the calf muscles while landing on the forefoot (Achilles avulsion), but shear-compression forces may also play a role. The avulsion fracture pattern is more common in elderly women, in whom osteoporosis plays a role.


Clinical Presentation


Pain, swelling, bruising, and an inability to bear weight are common symptoms of this injury. The patient may report pain and difficulty with stair climbing or walking on tiptoe as a result of weak plantarflexion. If the fracture fragment is significantly displaced, tenting of the skin posteriorly may be apparent.


Imaging


A standard lateral view of the foot demonstrates this fracture and the amount of displacement ( Figure 14-7 ). The most important factor in the definitive management of calcaneal tuberosity fractures is the amount of displacement of the avulsed fragment.




FIGURE 14-7


Avulsion fracture of the superior portion of the calcaneal tuberosity with significant displacement.


Indications for Orthopedic Referral


To restore the Achilles tendon to its original length, displaced fractures should be referred to an orthopedic surgeon within the first 7 to 10 days for ORIF.


Follow-up Care


Nondisplaced or minimally displaced fractures of the calcaneal tuberosity heal well with closed treatment. After acute treatment, the patient should be placed in a short-leg non–weight-bearing cast with the foot in 5 to 10 degrees of equinus for 6 weeks. Follow-up radiographs should be obtained 1 week after casting to ensure that the fracture fragments are still well aligned. Rehabilitation after immobilization should emphasize Achilles stretching and ankle and foot ROM and strengthening exercises.


Return to Work or Sports


The period of immobilization is relatively short compared with the total time required to return to a full preinjury activity level. Because of the length of immobilization in the equinus position, the patient requires a longer rehabilitation period to restore normal ankle motion (usually 3 to 6 months). Diligent effort during the rehabilitation period should help patients return to more physically demanding activities sooner. Those in more sedentary jobs should be able to work throughout the period of immobilization and rehabilitation. Return to activities that put the patient at risk of reinjury should be avoided for 3 to 4 weeks after immobilization is discontinued.


Extraarticular Fracture: Sustentaculum Tali


Mechanism of Injury


Fractures of the sustentaculum tali are among the least common of all calcaneus fractures. They more often occur in combination with other fractures than as isolated fractures. The usual cause is a fall onto the heel with significant inversion of the ankle.


Clinical Presentation


This fracture usually causes pain and swelling over the medial aspect of the heel. Inversion of the ankle causes increased pain resulting from compression of the fracture against the medial malleolus. An indication of diagnosis is pain below the medial malleolus that is made worse with passive hyperextension of the great toe. This maneuver stretches the flexor hallucis longus tendon, which courses beneath the fractured sustentaculum.


Imaging


A standard calcaneal series should demonstrate this fracture, with particular attention paid to the axial view. Oblique axial views may also be helpful. If presence of this fracture is in doubt, comparison views of the uninjured foot may be necessary for confirmation.


Indications for Orthopedic Referral


If the fracture is significantly displaced (usually inferiorly), closed reduction should be attempted. Infrequently, patients with a persistently painful nonunion require late referral for consideration of surgical excision of the fracture fragment.


Follow-up Care


Isolated nondisplaced fractures of the sustentaculum tali have a good prognosis. Immobilization in a non–weight-bearing short-leg cast for 6 to 8 weeks should achieve satisfactory results. Radiographs taken at the conclusion of immobilization should demonstrate evidence of callus formation. Rehabilitation after casting includes ankle and foot ROM and strengthening exercises.


Return to Work or Sports


The total time required to return to a full preinjury activity level varies, but diligent effort during the rehabilitation should help patients return to more physically demanding activities sooner. Those in more sedentary jobs should be able to work throughout the period of immobilization and rehabilitation. Return to activities that put the patient at risk of reinjury should be avoided for 3 to 4 weeks after immobilization is discontinued.


Extraarticular Fracture: Body Not Involving the Subtalar Joint


Mechanism of Injury


Fractures of the body of the calcaneus that do not involve the subtalar joint are less common than intraarticular fractures but have a similar cause of injury. Most often, the patient reports falling from a height and landing directly on the heel.


Clinical Presentation


Patients with this fracture complain of severe pain and swelling and an inability to bear weight. Ankle ROM is limited and painful. Swelling and bruising may be so severe that blisters form over the heel within the first 24 hours. Compartment syndrome may develop and compartment pressures should be measured if this is suspected.


Imaging


These fractures are usually seen on the lateral and axial views. Oblique radiographs and computed tomography (CT) should be strongly considered to rule out extension into the subtalar joint. A number of fracture configurations are possible, and the only consistent feature is lack of extension into the subtalar joint ( Figure 14-8 ). Single oblique fracture lines behind the posterior facet and significant comminution (“cracked eggshell”) are common. It is important to measure Bohler’s angle because it may be decreased even though the fracture line does not involve the subtalar joint.




FIGURE 14-8


A slightly comminuted fracture of the body of the calcaneus posterior to the subtalar joint ( arrow ). Note that the subtalar joint is intact.


Indications for Orthopedic Referral


Patients with displaced extraarticular fractures of the calcaneal body should be referred for consideration of reduction. Reduction may be necessary for certain types of displacement to minimize future disability, especially in younger patients. Fracture displacement that results in abnormal widening of the heel can lead to difficulty with shoe fitting or impingement of the peroneal tendons. Flattening of Bohler’s angle has the potential to shorten the Achilles tendon. Widening of the heel can usually be corrected with closed manipulation by using the palms to compress the heel medially and laterally. Restoration of Bohler’s angle is usually an open reduction procedure.


Follow-up Care


Use of ice and a bulky dressing early are important to minimize blister formation and skin loss or infection. Generally, if no subtalar involvement is evident, nondisplaced fractures of the body of the calcaneus heal well regardless of treatment. Cast immobilization is not necessary, and an early vigorous rehabilitation program including ROM exercises of the foot and ankle is actually advantageous. Nearly all patients with this fracture have a good outcome, and nonunion is rare. Patients should use toe-touch ambulation for 4 to 6 weeks followed by gradual progression to full weight bearing. Repeat radiographs should be obtained after clinical healing has occurred or in the event of delayed clinical healing.


Return to Work or Sports


Because early motion is allowed and encouraged in the rehabilitation of this fracture, most individuals can return to a full preinjury activity level within 2 to 3 months from the date of injury. Diligent effort during the rehabilitation should help patients return to more physically demanding activities sooner. Those in more sedentary jobs should be able to work throughout the healing period. Return to activities that put the patient at risk of reinjury should be avoided for 3 to 4 weeks after clinical healing has been achieved.


Intraarticular Fractures


Mechanism of Injury


Intraarticular fractures are the most common calcaneus fractures that primary care providers encounter. This fracture nearly always occurs after the patient falls from a height and lands on the heels, which absorb the full weight of the body. The injury depends more on the vector of force directed at the calcaneus than on the distance of the fall. As a result of vertical shearing or compression forces during the fall, the calcaneus is driven into the wedge-shaped LPT ( Figure 14-9 ).


Mar 11, 2019 | Posted by in CRITICAL CARE | Comments Off on Calcaneus and Other Tarsal Fractures
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