The Common Vein Copyright 2011
Definition
Fractures of the calcaneus are usually caused by a fall from a height or a motor vehicle accident. Twisting injuries can cause extraarticular fractures. Patients typically have other fractures including spinal fractures. and are often characterized by
Calcaneal fractures can be either open or closed injuries. The location of the fracture on the talus varies. The calcaneus can fracture either affect the joint in which case they are intraarticular or they mat be extraarticular.
Extraarticular fractures either involve the anterior process, tuberosity, medial process, sustentacular, body fracture (but not the subtalar articulation).
Intraarticular fractures are classified by the results of a CT scan for the Sanders Classification. Type I fractures are nondisplaced. Type II fractures are two-part fractures of the posterior facet. Type III fractures are three-part fractures that involve a central depression. Type IV fractures are highly comminuted involving the articulating surface.
The fracture may be complicated in the acute phase by neurovascular injury, or in the subacute or chronic phases by nonunion, malunion, infection, osteonecrosis, or osteoarthritis. Specific to calcaneal fractures are potential complications that include loss of subtalar motion, compartment syndrome, soft tissue injury, wound dehiscense, calcaneal osteomyelitis, increased heel width, peroneal tendonitis, sural nerve injury, chronic pain, reflex sympathetic dystrophy, and vascular injury.
The diagnosis of this injury is usually made by a combination of physical examination and x-ray imaging.
Imaging includes the use of plain x-rays, and if indicated CT-scan, or MRI.
Extraarticular fractures can be treated either nonoperative or operatively. Indications for nonoperative management include nondisplaced or minimally displaced fractures, patients weiht severe peripheral vascular disease or insulin dependent diabetics, significant other medical comorbidities, and large open wounds and life threatening injuries. A bulky Jones dressing is applied followed by a fracture boot with early ROM activities.
Intraarticular fractures are treated nonsurgically for type I fractures. Patients are non-weightbearing for 10 to 12 weeks with early ROM activities. Surgery is indicated for type II and III fractures between 10 to 14 days after the injury to allow for swelling to decrease. Type IV fractures may require a primary joint fusion.
This lateral examination of the normal foot shows the morphology and relationships of the calcaneus, talus and navicular bones.
Courtesy Ashley Davidoff MD labelled 46714b02.8
The axial section CT scan of the forefoot exemplifies the normal anatomy of the distal tibia, fibula, tibio-talar joint.
The talus is central to the stability of the joint
Courtesy Ashley Davidoff MD 72583c01
The image reflects a lateral projection of the left ankle of a normal adult and reveals the almost microscopic anatomy of the trabecular patterns in the component bones. The arrows represent at least two of the major vectors of the force, one (green arrow) toward the calcaneus (c), and the second (red arrows) toward the tarsals and metatarsals of the foot.
Image a is an inverted image so that bone that usually shows up as white is black and that which is usually black is white. This technique allows improved visualization of the trabeculae.
Two basic forces are shown that get divided and dissipated to the foot. The green arrows reflect a vertical force created by the weight of the person which is transmitted relatively posteriorly through the anterior part of the tibia via the talus (t) and then to the posterior part of the calcaneus (c). The trabecular pattern runs parallel to the force thus reinforcing the bone. The posterior and inferior aspect of the calcaneus is the final destination (“buck ends here!”) and this region is reinforced with compact bone. This compact bone is the thickest cortical bone of the foot and reflects the final destination of the vector of the (green arrow) force.
Some of posterior trabeculations of the tibia and the trabeculations of fibula are directed inferiorly and anteriorly along the other vector (red arrows). The anterior aspect of the talus and the anterior aspect of the calcaneus redirect this force (red arrows) toward the other tarsal bones and then toward the metatarsals and phalanges. The pattern of the trabeculations in horizontal direction therefore reflects the response of the bone to the forces imposed on them.
Courtesy Ashley Davidoff Copyright 2011 72326c12Lb01.8s
Courtesy Ashley Davidoff Copyright 2011 99816c031L.81s
The lateral examination of the calcaneus of a 64 year old female (4 years later) shows two screws traversing the previously identified distracted fracture, with not a trace of the former fracture line (region highlighted in black and white in b). Open reduction and internal fixation (ORIF) was required to bring the fragments together which allowed bridging of the trabeculae to take place.
Courtesy Ashley Davidoff Copyright 2011 99818c.81L
References
Davis MF, Davis PF, Ross DS. Expert Guide to Sports Medicine. ACP Series, 2005.
Elstrom J, Virkus W, Pankovich (eds), Handbook of Fractures (3rd edition), McGraw Hill, New York, NY, 2006.
Koval K, Zuckerman J (eds), Handbook of Fractures (3rd edition), Lippincott Williams & Wilkins, Philadelphia, PA, 2006.
Lieberman J (ed), AAOS Comprehensive Orthopaedic Review, American Academy of Orthopaedic Surgeons, 2008.
Moore K, Dalley A (eds), Clinically Oriented Anatomy (5th edition), Lippincott Williams & Wilkins, Philadelphia, PA, 2006.
Wheeless’s Textbook of Orthopaedics: Calcaneal Fracture (http://www.wheelessonline.com/ortho/calcaneal_fracture_1)