Brad J. Yoo
James E. Meeker

Bony Anatomy

The calcaneus is asymmetrically shaped, with multiple osseous prominences: the calcaneal tuberosity posteriorly, the sustentaculum tali medially, the anterior process anteriorly, and the peroneal tubercle laterally (Fig. 28-1).
There are four articular facets: the planar calcaneocuboid; the talar articulations: the anterior facet and middle facets; and the convex posterior facet.
Calcaneal fractures most commonly occur following a severe axial load.
Axial force and subtalar eversion result in the lateral talar process striking the superior margin of the critical angle of Gissane as a fulcrum, resulting in primary and secondary fracture lines.
Primary fracture line: Originates superolaterally, distal to posterior facet articular cartilage margin, and exits medially, caudal to the sustentaculum tali. Two fragments are created: the tuberosity/posterior facet¹ and the anterior process/medial facet² (Fig. 28-2).
Secondary fracture lines created depending upon the energy absorbed and the foot position at time of impact. Distally, stellate fractures in the sagittal plane are common extending into the calcaneocuboid articulation or middle facet. Proximally, fracture lines may occur in the sagittal plane or the axial plane. If a sagittal plane fracture occurs proximally from fracture origination, a separate osteochondral fragment of the posterior facet is created (Essex-Lopresti joint depression fracture). If an axial plane fracture occurs proximally from fracture origination, the tuberosity is detached as a separate fragment with or without a variable portion of the posterior facet (Essex-Lopresti tongue-type fracture) (Fig. 28-3).
Common deformities visualized on a lateral x-ray include (1) calcaneal height loss, (2) calcaneal length loss, and (3) incongruity of the posterior talocalcaneal facet (Fig. 28-4).³
Common deformities visualized on a Harris axial x-ray include (1) the primary fracture line; (2) varus tuberosity malpositioning; (3) calcaneal width increase, with pathologic lateral translation of the lateral calcaneal wall; and (4) involvement of the posterior facet (Fig. 28-5).
Soft tissue injuries are almost as important to determining treatment if not more than the fracture pattern.³ They are not well visualized radiographically, but require close physical examination for proper assessment and optimal outcomes.
The affected foot and ankle should not demonstrate significant swelling prior to operative intervention. Soft tissue readiness is heralded by the appearance of fine soft tissue wrinkles and the mobility of the skin over the underlying connective tissue. Failure to wait for soft tissue quiescence increases the risk of soft tissue wound complications and infection (Fig. 28-6).

Gardner1e-ch028-image001 — Figure 28-1 Lateral calcaneus normal anatomy.

Gardner1e-ch028-image002 — Figure 28-2 The primary fracture line with the creation of two major fragments, the tuberosity and posterior facet segment (1) and the anterior process and sustentacular segment (2).

Gardner1e-ch028-image003 — Figure 28-3 Tongue-type calcaneus fracture.

Gardner1e-ch028-image004 — Figure 28-4 Joint depression calcaneus fracture.

Gardner1e-ch028-image005 — Figure 28-5 Fracture preoperative calcaneus Harris axial.

Gardner1e-ch028-image006 — Figure 28-6 Wrinkled foot.

Radiographic Anatomy

Orthogonal x-rays for calcaneus evaluation include a lateral heel view, a Harris-Beath axial view, and an AP view of the foot.
Lateral heel view identifies posterior facet involvement, Bohler’s angle, (critical) angle of Gissane, and tuberosity position (cranial migration) (Fig. 28-7).
Axial view (Harris-Beath) visualizes tuberosity position (varus-valgus), primary fracture line, calcaneal height loss, calcaneal widening, and a portion of the posterior facet (Fig. 28-8).
AP view of the foot exhibits secondary fracture lines into the anterior process and incongruity of the calcaneocuboid joint (Fig. 28-9).
Radiographs can be obtained from multiple perspectives to obtain a comprehensive assessment of the posterior facet (Broden x-ray views) (Fig. 28-10).⁴
Computed tomography clarifies fracture line configuration. Sagittal and coronal reconstructed images may further help understanding of fracture patterns. Axial, coronal, and sagittal CT images below depict a significantly comminuted, intra-articular calcaneal fracture with joint depression, lateral wall blowout, widening, shortening, and ankle subluxation (Fig. 28-11).

Gardner1e-ch028-image007 — Figure 28-7 Calcaneus lateral x-ray.

Gardner1e-ch028-image008 — Figure 28-8 Harris-Beath calcaneus intact.

Gardner1e-ch028-image009 — Figure 28-9 AP foot normal anatomy.

Gardner1e-ch028-image010 — Figure 28-10 Broden’s view.

Gardner1e-ch028-image011 — Figure 28-11 CT images.

Surgical Positioning and Imaging

The extensile lateral approach (Letournel) requires positioning the patient in the lateral position. The patient is positioned with the uninjured side down. Note that a prone position on padded jelly rolls may be considered in cases of bilateral calcaneal fractures undergoing ORIF.
A tourniquet is placed around the operative thigh prior to lateral positioning to facilitate ease of application and proper application.
An axillary roll is used to facilitate lung ventilation and release pressure upon the down side brachial plexus. The ipsilateral arm may be suspended with a well-padded arm holder.
Preoperative saved images of the contralateral Harris axial and lateral radiographs will serve as an invaluable template to model fracture reduction upon.
A radiolucent table is critical for proper intraoperative imaging.
Folded blankets or speciality pillows are used to support the operative limb at an elevated position compared with the down, nonoperative limb. The operative limb is flexed, while the nonoperative limb is positioned with knee extension. This permits lateral intraoperative radiographs without overlap with the nonoperative limb. With knee flexion, the tendoachilles is more relaxed, which helps with tuberosity reduction (Fig. 28-12).
Intraoperative calcaneus radiography is facilitated by placing the operative limb in the distal posterior corner of the radiolucent operative table.
In this position, the C-arm may be introduced into the surgical field from the foot of the bed. Lateral radiographs may be readily obtained (Fig. 28-13).
Positioning the C-arm parallel with the floor will allow a Harris axial view (Fig. 28-14).
The C-arm may be kept parallel with the floor but repositioned perpendicular to the Harris axial view to obtain an AP view of the foot. Another option is to utilize the lateral C-arm position and rotate the limb (via the hip) to obtain an AP foot view (Fig. 28-15).
Broden views permit subtalar articular assessment.
Broden described an imaging series to show the articular surface of the posterior facet. This can be helpful in evaluating fracture displacement preoperatively and also quality of the reduction during surgery.
- Broden views can be obtained with the patient in the lateral position. The ankle is held in neutral position with respect to dorsiflexion and plantar flexion.
- The fluoro beam is directed through the subtalar joint at an angle that is 45 degrees from true lateral (i.e., positioned half way between AP ankle and true lateral ankle).
- The four Broden projections are obtained with the beam tilted 10, 20, 30, and 40 degrees cephalad. This permits evaluation of fracture lines and displacement along the majority of the posterior facet.
  - The 10-degree tilt images the posterior aspect of the joint while the 40-degree view images the anterior aspect.
  - The 20- and 30-degree views show the midportion of the posterior facet and are best at demonstrating the sustentaculotalar articulation (Fig. 28-16).