Calcaneus Fractures 

Updated: Aug 30, 2018
Author: Scott Nicklebur, MD; Chief Editor: Vinod K Panchbhavi, MD, FACS 

Overview

Background

Fractures of the calcaneus, or os calcis, have been observed and documented for centuries.[1]  However, a true consensus regarding the management of these fractures has long eluded practitioners.[2]

Norris correctly described a compression mechanism in calcaneus fractures in 1839, and in 1843, Malgaigne described two types of calcaneal fractures; this description formed the first rudimentary classification system. With the advent of radiographic evaluation, several authors developed classification systems, including Bohler (in 1931), Essex-Lopresti (in 1951-2), Rowe et al (in 1963), and others.[3, 4, 5, 6, 7, 8] Essex-Lopresti first sought to distinguish intra-articular fractures of the calcaneus from extra-articular ones, correctly associating the intra-articular variety with a poorer long-term prognosis.

The poor correlation of these comprehensive classification systems with functional outcomes hindered their widespread acceptance.[9, 10, 11] Only with the advent of computed tomography (CT) was the capability to evaluate accurately complex calcaneus injuries realized. Current classification systems based on CT appearances, such as the one Sanders described, appear to provide more reliable indicators of prognosis and are better able to select injuries that are particularly amenable to surgical intervention.[12, 13, 14]

Despite improvements in imaging, as well as a better understanding of the patterns of injury in complex fractures of the calcaneus, opinions on the management of such injuries continue to differ.[15, 16] Prospective studies have attempted to show benefit either with early operative intervention or with nonoperative measures.[17, 18, 19] Each modality has at times enjoyed more attention and enthusiasm in the literature. A frustrating factor that perpetuates this disagreement is the subset of calcaneus fractures with poor long-term outcomes, regardless of management. Cotton commented in 1916 that "the man who breaks his heel bone is done so far as his industrial future is concerned."[20]

For patient education resources, see the First Aid and Injuries Center, as well as Broken Foot, Understanding X-rays, and Cast Care.

Anatomy

The calcaneus (os calcis) is the largest of the tarsal bones. The calcaneus has four articular facets, which allow it to articulate with the talus superiorly and the cuboid anteriorly. The three subtalar facets (anterior, middle, and posterior) must function as a unit, and any fracture that interrupts their alignment is, by definition, an intra-articular fracture. The posterior facet is a major weightbearing surface, though the anterior and middle facets bear more weight per unit area.

The calcaneal composition has a significant influence on preoperative planning. The body of the calcaneus is composed primarily of cancellous bone, having a comparatively thin cortex. There are, however, several important areas of increased bony density that are particularly amenable to screw placement, including the following:

  • Angle of Gissane
  • Plantar posterior tubercle
  • Anterior aspect of the anterior process
  • Sustentaculum tali

The tibial artery, nerve, posterior tibial tendon, and flexor hallucis longus tendon course along the medial wall of the calcaneus, though they are rarely damaged in calcaneus fractures caused by blunt force. These structures are thought to be shielded by the medial projection of the sustentaculum tali, which is held in place by the medial talocalcaneal interosseous ligaments during fracture of the calcaneus. Laterally, the peroneal tubercle provides a groove for the peroneal tendons (the brevis superiorly and the longus inferiorly). (See Ankle Joint Anatomy.)

Pathophysiology

The mechanism of injury in calcaneus fractures typically involves a high-energy axial load applied to the heel, which drives the talus downward onto the calcaneus. The resultant primary fracture line extends from the lateral aspect of the angle of Gissane in a posteromedial direction, initiating an oblique, primary fracture line. It is from this point that multiple secondary fracture lines may develop. The subtalar joint is involved 75% of the time.

Essex-Lopresti described the following two calcaneus fracture subtypes[4] :

  • Joint-depression fractures
  • Tongue-type fractures

Both of these describe the primary fracture line. In the tongue-type fracture, the secondary fracture line directly extends in a posterior direction, producing a large superior, posterior, and lateral fragment, with the remainder of the calcaneal body forming the inferior fragment. In the more frequent joint-depression fracture, the secondary fracture line begins at the angle of Gissane and extends posteriorly but deviates dorsally to exit the bone just posterior to the posterior articular facet. This fracture fragment contains most of the posterior facet.

Etiology

Nearly all intra-articular fractures of the calcaneus are caused by an axial loading mechanism, which is directed through the laterally situated (in relation to the weightbearing axis of the lower extremity) plantar tuberosity of the calcaneus. Causes of fractures include the following:

  • Fall from height (usually ≥6 ft [~1.8 m])
  • Motor vehicle collisions
  • Impact on a hard surface while running or jumping
  • Extra-articular fracture of the calcaneal body and plantar tuberosity caused by blunt-force injury
  • Avulsion injuries with abrupt contraction of the Achilles tendon
  • Overuse injury, or stress fracture, in athletes

Extra-articular injuries are more likely to occur with a sudden twisting force applied to the hindfoot than with other mechanisms.

Epidemiology

Calcaneus injuries represent 2% of all fractures seen in adults. The os calcis is the most frequently fractured tarsal bone, accounting for more than 60% of tarsal fractures. Calcaneus fractures are most commonly seen in young men.

Extra-articular fractures account for 30% of all calcaneus fractures in adults. The most common extra-articular fracture is a calcaneal body fracture. Fractures of the anterior process represent 10-15% of extra-articular injuries; these are the only type of calcaneus fractures that are more common in women than in men. Fractures of the superior tuberosity beak or avulsion fractures represent 10% of extra-articular injuries. Sustentaculum tali fractures are rarely seen as isolated injuries.

Intra-articular fractures constitute 70% of all calcaneus fractures in adults.

Calcaneus fractures are rarely encountered as open fractures. Open injuries that have been reported have occurred in only 2% of cases.

Prognosis

As Essex-Lopresti correctly noted 50 years ago, intra-articular fractures of the calcaneus result in morbidity figures substantially higher than those of extra-articular fractures.

Zhang et al prospectively compared a minimally invasive lateral approach with a conventional sinus tarsi approach for displaced intra-articular (Sanders type II, III, and IV) fractures of the calcaneus.[21] Whereas the minimally invasive approach resulted in a lower postoperative complication rate for Sanders type II and III injuries, functional outcomes were similar. The sinus tarsi approach yielded statistically significant improvements in functional outcomes over the minimally invasive approach, but this was limited to patients with Sanders type IV injuries.

Schuberth et al performed a retrospective study of 24 cases of minimally invasive open reduction and internal fixation (ORIF) of intra-articular calcaneal fractures.[22] Postoperatively, there were significant changes in articular stepoff of the posterior facet, medial-wall displacement, and the Boehler angle. No soft-tissue complications occurred, and none of the 18 patients followed for more than 1 year progressed to subtalar fusion. The authors concluded that a minimally invasive approach can improve radiographic parameters consistent with the goals of restoration of articular congruity, calcaneal morphology, and calcaneal height and can achieve satisfactory results with minimal risk of wound complication.

Grala et al reported on two groups of patients who underwent operative treatment for articular fractures of the calcaneus, one (N = 23) treated by standard reconstruction and the other (N =19) treated with a large bone distractor.[23]  Patients in whom the distractor was used had shorter operating times, and less effort was required in performing the surgery. The bone distractor apaprently retracted the soft-tissue flap, helped reduce the articular and tuberosity fragment, and improved visualization by distracting the posterior talocalcaneal joint. All fractures healed well or very well.

Dhillon et al performed a prospective evaluation comparing results in 16 patients who had open fractures treated with minimally invasive surgery (MIS; group 1) and nine patients who had closed fractures treated with ORIF (group 2).[24]  At 1 year, group 1 had a mean Maryland Foot Score (MFS) of 79 and an American Orthopaedic Foot and Ankle Society (AOFAS) score of 77.37, whereas group 2 had an MFS of 84.4 and and AOFAS score of 86.1. The authors concluded that MIS can achieve acceptable fracture reduction and that it can serve as the primary definitive treatment option for open fractures of the calcaneus.

Eckstein et al reported long-term (≥20 years) follow-up of 22 patients who underwent surgical treatment of displaced calcaneal fractures.[25] Assessment involved a combination of radiography with Short Form (SF)-36 and AOFAS questionnaires. At follow-up, only 12 of the 22 patients (55%) of the patients had very good or good clinical results; four had average results, and six had poor results. The results of this study did not lend support to the view that ORIF yields better outcomes than conservative therapy for these fractures.

 

Presentation

History

A history of a fall from height, a motor vehicle accident (particularly with the patient sitting in the front of the vehicle, where contact with the floorboards is more likely), or a similar mechanism should suggest a possible injury to the hindfoot. Patients are more likely to be young male individuals with intra-articular injuries.

Inquire about other areas of injury or pain. The discomfort associated with a fracture of the calcaneus may be so distracting to the patient that other significant injuries are ignored. Compression fractures of the spine are common (seen in 10-15% of cases), as are compression-type injuries to other areas of the bony skeleton, such as the proximal femur.

Document chronic medical conditions such as diabetes, peripheral vascular disease, or malignancy. Ask about prior injuries or surgeries in the affected area. In case of prior injury or surgery, ask about any orthopedic hardware that might be present.

Determine current and recent medication use, and inquire as to social habits such as alcohol and tobacco consumption.

Physical Examination

Patients with a fracture of the calcaneus may present with the following:

  • Pain
  • Edema
  • Ecchymosis
  • Deformity of the heel or plantar arch
  • Inability to bear weight on the injured foot

Observe all areas for evidence of open injury, particularly areas with overlying lacerations.

Hold the heel of the patient's foot in the palm of the hand, and gently squeeze. Elicited pain suggests calcaneal fracture.

Examine closely for evidence of ecchymosis, particularly that which tracks distally to the sole of the foot. This particular pattern of ecchymosis, known as the Mondor sign, is pathognomonic for calcaneal fracture.

Check for posterior tibial and dorsalis pedis pulses, and compare these to the uninjured side. Ensure that distal capillary refill is 2 seconds or less.

Pay particular attention to the presence of any paresthesia, edema, pallor, diminished pulses, or severe pain with passive flexion of the toes that might suggest compartment syndrome of the foot.

Examine the knee, ankle, and midfoot for tenderness, ecchymosis, or swelling. Radiographs of the knee, ankle, and foot may be indicated if positive findings are noted.

Inspect and palpate other areas at high risk for fracture, such as the medial, lateral, and posterior malleoli, as well as the base of the fifth metatarsal.

As many as 7% of patients with a calcaneus fracture may have fracture of the contralateral heel. Given the appropriate mechanism of injury (ie, a fall from height), care must be taken to examine both lower extremities thoroughly to exclude the presence of bilateral injuries.

 

Workup

Laboratory Studies

The need for preoperative, or screening, laboratory studies usually depends on the extent of other injuries and the presence of comorbid medical conditions. A complete blood count (CBC), blood typing, coagulation profile evaluation, and electrocardiography (ECG) are reasonable preoperative studies in calcaneus injuries. Additional studies, if warranted, are selected on a patient-by-patient basis and are usually ordered at the discretion of the physician performing the preoperative clearance examination.

Plain Radiography

Plain radiographs of the foot are indicated for any suspected calcaneus injury. Also, consider imaging the contralateral ankle and foot for comparative purposes. Images should include anteroposterior (AP), lateral, oblique, axial, and Broden views.

AP radiographs are needed to evaluate calcaneocuboid joint involvement, talonavicular subluxation, and lateral-wall widening. AP views of the ankle are used to assess subfibular impingement as a result of lateral displacement of the lateral wall of the calcaneus.

Lateral radiographs of the foot are needed to evaluate the Bohler angle. This angle is defined by two intersecting lines: one drawn from the anterior process of the calcaneus to the peak of the posterior articular surface and a second drawn from the peak of the posterior articular surface to the peak of the posterior tuberosity. The average Bohler angle is 25-40°. In severe fractures with subtalar joint involvement, this angle may decrease or become negative. (See the image below.)

Calcaneus fractures. Comminuted fracture of calcan Calcaneus fractures. Comminuted fracture of calcaneus sustained in motorcycle accident. Note loss of Bohler angle.

Oblique views show the degree of displacement of the primary fracture line and the lesser facets.

Axial views depict the primary fracture line, varus malposition, posterior facet stepoff, lateral-wall displacement, and fibular abutment. (See the image below.)

Calcaneus fractures. Axial radiograph reveals comm Calcaneus fractures. Axial radiograph reveals comminuted fracture of calcaneal body.

Broden views of the foot are obtained by internally rotating the leg 45° with the ankle in neutral position. The beam may then be directed toward the lateral malleolus and advanced cephalad at intervals of 10°, 20°, 30°, and 40° to fully evaluate the posterior facet.[26]

Computed Tomography

Computed tomography (CT) has revolutionized the diagnosis, treatment, and ability to render accurate prognoses of fractures of the calcaneus. CT results also form the basis of many of the current systems for classifying calcaneus fractures. CT-based classifications categorize intra-articular injuries according to the comminution and displacement of the posterior facet. (See the image below.)

Calcaneus fractures. Bilateral calcaneus fractures Calcaneus fractures. Bilateral calcaneus fractures sustained in motor vehicle collision. Compare minimally displaced calcaneal tuberosity fracture on patient's left side with comminuted intra-articular (Sanders type III) fracture on right.

The patient should be positioned on the imaging table with his or her hips and knees flexed. Axial and coronal sectional images are then obtained with a minimum interval of 2 mm. Axial views enable good visualization of the talonavicular and calcaneocuboid joints, the anteroinferior aspect of the posterior facet, the sustentaculum tali, and the lateral calcaneal wall. Coronal views are then oriented perpendicular to the posterior facet. These views are important for distinguishing injury to the posterior facet.

 

Treatment

Approach Considerations

The use of nonoperative versus operative interventions for calcaneus fractures remains a controversial topic.[2] Treatment goals of operative modalities include the following:

  • Restoration of heel height and length
  • Realignment of the posterior facet of the subtalar joint
  • Restoration of the mechanical axis of the hindfoot

With these treatment goals in mind, current trends in orthopedics support the following approaches.[27, 28]

Extra-articular fractures are generally treated in a closed manner. Exceptions include fractures of the sustentaculum tali with displacement of more than 2 mm, posterior avulsion fractures, and significant fractures of the calcaneal body.

Intra-articular fractures may be treated in a closed fashion, but they are more commonly treated with a combination of open reduction, ostectomy, osteotomy, internal fixation, and/or arthrodesis of the subtalar and calcaneocuboid joints. Nondisplaced (Sanders type I) intra-articular fractures are generally treated in a closed fashion. Severely comminuted (Sanders type IV) intra-articular fractures may be treated with a combination of open reduction and internal fixation (ORIF) and arthrodesis of the subtalar joint.[29]

Other factors influencing the choice between nonoperative and operative intervention include the following:

  • Patient age
  • Comorbid health conditions
  • Concurrent injuries

Surgery for calcaneus fractures should be delayed, ideally for 10-14 days, in the presence of significant edema or fracture blister formation.[30] Exceptions to this rule include open fractures and the presence of a compartment syndrome in the foot, which should prompt immediate surgery for appropriate intervention.[31]

In their report of a prospective, randomized study, Buckley et al suggested that the functional results after operative fixation of displaced intra-articular calcaneus fractures were better than those undergoing nonoperative treatment, in selected groups.[32] Further prospective studies are required to validate these results.[33]

Zhang et al performed a meta-analysis of seven randomized controlled trials (N = 908) comparing operative treatment of displaced intra-articular calcaneal fractures with nonoperative treatment.[34]  Although correctly performed surgery yielded improvements in shoe wear and gait patterns, these benefits were countered by increases in complications (prmarily wound-related). Treatment groups did not differ significantly with respect to American Orthopaedic Foot and Ankle Society (AOFAS) score, Short Form (SF)-36, return to work, rate of subsequent talar fusion, or incidence of reflex sympathetic dystrophy.

Medical Therapy

Nonoperative treatment of calcaneus fractures requires the cooperation of a multidisciplinary team involving an orthotist, a physical therapist, an occupational therapist, and a surgeon familiar with the pattern of injury involved.

Most extra-articular calcaneus fractures are managed nonoperatively, provided that the injury does not change the weightbearing surface of the foot and provided that it does not alter hindfoot biomechanics.[35] Severely comminuted intra-articular fractures may be managed nonoperatively, particularly when reconstruction is likely to be unsuccessful.[36]

Closed reduction may be attempted by plantarly displacing both the forefoot and the hindfoot to reverse the mechanism of injury, which allows for elevation of the posterior facet. However, this approach rarely results in durable maintenance of the reduction.

Many authors recommend short leg casting and no weightbearing for 2 weeks, followed by range-of-motion (ROM) exercises. Progressive weightbearing should begin at 8 weeks, with full weightbearing by 12 weeks.

Surgical Therapy

Multiple surgical approaches are available for treatment of calcaneus fractures, ranging from minimally invasive techniques[37] (eg, percutaneous fixation[22] ) to extensive open techniques. Open techniques may be performed by using medial, lateral, or combined approaches, depending on the extent of injury and the location of the fracture fragments.[38, 39, 23, 40] (See the images below.)

Calcaneus fractures. Avulsion-type fracture of cal Calcaneus fractures. Avulsion-type fracture of calcaneus, sustained when patient fell 6 ft from ladder onto solid ground. Because of distraction of fracture fragments, injury was treated with open reduction and internal fixation.
Calcaneus fractures. Status post open reduction an Calcaneus fractures. Status post open reduction and internal fixation.

ORIF of a calcaneus fracture is made difficult by the complex anatomy, the presence of soft cancellous bone (which is not amenable to screw fixation), and the high incidence of postoperative wound infection and breakdown.

Most reports suggest that the functional outcome is related to the accuracy of the subtalar joint reduction, the restoration of normal heel morphology, the status regarding subfibular decompression, and the implementation of postoperative measures to decrease swelling.

Operative details

Preoperatively, a comprehensive physical examination must be undertaken. One should exercise care to avoid overlooking additional injuries of the musculoskeletal system. Some 10-15% of trauma patients with a fracture of the calcaneus have a concomitant spinal injury. A full history, including documentation of preexisting medical conditions such as diabetes or vascular disease, should not be unnecessarily delayed.

A multidisciplinary team consisting of the surgeon, the anesthesiologist, and the physician who is providing preoperative clearance should all be involved in planning the procedure (if indicated). Knowledge of the relevant anatomy is important, as is having clear and comprehensive images of the injury. Thorough imaging allows for careful determination of the surgical approach and for planning of a staged procedure, if necessary.

The timing of surgery is an important factor in determining surgical success, as measured by long-term functional outcomes. Ideally, surgery should occur within 3 weeks after injury. This period allows for any swelling and fracture blisters to resolve completely, but the procedure is still sufficiently early to prevent premature healing and coalescence of the fracture fragments. In the absence of fracture blisters, the return of normal skin wrinkling is an indication that significant swelling has resolved and operative intervention may proceed.

Compared with open procedures, closed reduction with percutaneous fixation has a lower risk of wound complications, a shorter operating time, and more rapid healing because the soft tissue is handled less.[41, 42, 43] This approach is indicated in patients with significant comorbidities, soft-tissue compromise or impaired healing, or true tongue-type fracture patterns. The goals of this approach include improvement of heel alignment and reduction of the posterior facet. Unfortunately, the limited exposure that this technique affords sometimes prevents adequate reduction and fixation of the calcaneal injury. If anatomic joint reduction is sought, ORIF may be a preferred option.

Calcaneal ORIF has improved as a result of enhanced preoperative evaluation with computed tomography (CT). Enhancements in equipment and surgical technique, particularly in the area of soft-tissue handling, have also improved its surgical success rates. Another exciting development is the use of subtalar arthroscopy (as Rammelt et al described) for accurate evaluation of the posterior facet after the initial reduction is performed.[44, 45]

The most popular incision for exposure during ORIF of calcaneus fractures is an extensile lateral approach.[38] This approach allows the surgeon to visualize the entire fracture. It also allows complete reduction from the tuberosity to the anterior process and the calcaneocuboid joint. In addition, this approach permits indirect reduction of the medial wall and the sustentaculum.

The extensile lateral approach should include a full-thickness skin flap. Gentle tissue handling is a must, and adequate wound closure is equally important. Flap closure that avoids excessive tension on the skin is critical to prevent skin necrosis.[46] The use of thin plates in calcaneal fixation has significantly addressed the issue of excessive skin tension, hardware prominence, and subsequent wound breakdown.

Zwipp et al described the use of a locking nail system for internal fixation of 106 displaced intra-articular calcaneal fractures (15 percutaneously and 91 via a sinus tarsi approach), in an effort to reduce the complications associated with extensile approaches.[47]  They noted a low incidence of soft-tissue complications (superficial wound edge necrosis, 1.9%; deep infection, 0.9%), improved Bohler angles (from 7.3º to 31.2º at 3 months), and good AOFAS scores (89.5 at 6 months and 92.6 at 12 months). They further noted that the locking nail was not designed to accomplish reduction and that joint congruity and calcaneal shape must be restored before nails are inserted.

Postoperative Care

A small suction drain is frequently used after ORIF. This drain is typically removed when less than 10 mL of drainage fluid is collected over 8 hours.

Postoperatively, the foot is elevated with the ankle in the standard neutral position of a 90° angle between the foot and the tibia. This position is maintained for up to 72 hours to reduce postoperative swelling.

Early ROM exercises are encouraged after the surgical incision has begun healing, usually 10-12 days after surgery. A well-fitting orthosis is provided for comfort and to prevent gastrocnemius-soleus contracture. Sutures are removed at 2-3 weeks, but weightbearing is delayed for up to 12 weeks, depending on the original degree of comminution and the subsequent rigidity of the fixation.

Complications

A frequent complication of a calcaneus fracture is chronic disability due to the pain of an improperly functioning subtalar or calcaneocuboid joint.[48]

Specific complications after ORIF of calcaneus fractures include the following:

  • Infection
  • Pain
  • Swelling
  • Delayed wound healing
  • Nonunion of the fracture fragments

Lateral impingement of the peroneal tendon can occur as a result of decreased calcaneal height. Occasionally, damage to the sural nerve occurs with a lateral surgical approach.[49]

Minimally invasive surgical approaches to calcaneus fractures may be associated with lower complication rates.[50, 51]

Long-Term Monitoring

An entire year may be required to fully assess patients for residual disability that occurs after a fracture of the calcaneus.[52, 33]

Supervised physical therapy may be of substantial benefit, both during the nonweightbearing period and during the active weightbearing recovery phase.