How To Evaluate And Treat Calcaneal Fractures

   Calcaneal fractures continue to be one of the most complicated injuries of the lower extremity. Satisfactory outcomes are difficult to achieve and require extensive experience and understanding in treating the injury. Calcaneal fractures are much like pilon fractures of the distal tibia in that they are severe soft tissue injuries complicated by fracture of the heel bone. The importance of the soft tissue envelope cannot be overstated.    There continues to be a wide range of treatment strategies despite the significant ongoing research on this injury. Cast immobilization, percutaneous pinning, limited open approaches, extensile open approaches and fine wire external fixation have all been reported. However, there is still no clear standard in the approach to these complex fractures.    Having a strong knowledge of the anatomy of the calcaneus is paramount to understanding the fracture patterns one may see with these injuries. The calcaneus has a thin cortical shell laterally with its interior consisting of cancellous bone. Medially, the sustentaculum tali is made up of dense cortical bone with strong ligamentous attachments to the talus. There is also very thick cortical bone that supports the facets on the superior surface of the calcaneus. This dense cortical bone forms an angle of 120 to 145 degrees (Gissane’s crucial angle). Directly under this dense bone is the neutral triangle, an area relatively void of trabecular patterns. This lies directly under the lateral process of the talus. Anteriorly, the calcaneus articulates with the cuboid and transitions to the lateral column of the foot.    Intraarticular calcaneal fractures are the result of an axial load with varying degrees of shear force. The shear forces are dictated by the position of the calcaneus in relation to the talus at the time of axial load. Calcaneal fractures typically result from a fall from varying heights or a motor vehicle accident. The characteristics of these fractures result from the amount of applied force, the quality of bone and the relationship of the talus and calcaneus (i.e. position of the foot).1,2 This talocalcaneal relationship may change throughout impact depending on the injuring force. This leads to the subtle variations in every fracture.    The initial axial load causes the impacting of the calcaneus into the talus. The lateral process of the talus then acts like a wedge into the dense cortical bone at the crucial angle of Gissane.3 Once the cortical bone has failed, the lack of dense bone in the neutral triangle offers little resistance to the applied forces. The resulting primary fracture line is oriented from superolateral to inferomedial, producing a posterolateral tuberosity fragment and a medial sustentacular fragment.2    Each main fragment will have a portion of the posterior facet. This primary fracture line will exit laterally beneath the lateral talar process or extend anteriorly and involve the calcaneocuboid joint. The tuberosity fragment is often plantarflexed (due to the Achilles tendon influence) and displaced laterally against the fibula. However, the sustentacular fragment is usually in anatomic alignment with respect to the talus due to the strong ligamentous attachments. Where the primary fracture line starts in the posterior facet is dependent on the relationship of the talus and calcaneus. An inverted foot will cause the fracture line to start more medially while an everted foot will cause the fracture line to begin laterally.4 The more eccentrically positioned the calcaneus is in relation to the talus, the more shear forces that are applied during axial load. Conversely, an inverted foot results in more direct axial forces and less shear forces.    As the axial and varying shear forces continue, a secondary fracture line develops. In joint depression fractures, the secondary fracture line runs posteriorly to the posterior facet. This leaves a portion of the facet (depending on where the primary fracture line started) free to depress into the calcaneal tuberosity and separate this part of the facet from the tuberosity fragment.    One may also see varying degrees of comminution and typical expansion of the lateral wall of the calcaneus. The free portion of the posterior facet is impacted into the body of the calcaneus and may rotate anteriorly up to 90 degrees. On the other hand, tongue-type fractures result from the secondary fracture line extending posteriorly into the tuberosity. The posterior facet is not impacted into the body of the calcaneus with this pattern and the tuberosity and lateral aspect of the posterior facet remain aligned.

What You Should Look For In The Clinical Evaluation

   The axial forces that often result in calcaneal fractures mandate a complete head to toe evaluation. Associated injuries are common and one must have a high index of clinical suspicion. Typically, emergency personnel evaluate these patients and stabilize them prior to the foot and ankle surgeon’s involvement. However, many subtle injuries can go unrecognized until pain from more critical injuries subsides.    The overall morphology of the hindfoot is usually disrupted. One will often see significant edema and ecchymosis with widening and shortening of the heel. It is critical to evaluate for any open wounds. There may be profound wounds with extensive bone exposure or one may note a subtle puncture from the medial sustentacular spike.5 Any open wounds require adherence to the management protocol for open fractures.    Fracture blisters are not uncommon. These blisters typically form in areas of absent or sparse sweat glands or hair follicles as these structures help to anchor the dermal-epidermal junction.6 As the swelling increases, the fluid takes the path of least resistance and separation occurs between the dermis and epidermis. Blood filled blisters are the result of deeper injury and damage to the dermal and subdermal layers while clear blisters remain within the dermis.    Surgeons may also frequently encounter compartment syndromes with this injury. Signs of compartment syndrome include severe, relentless, burning pain that typically cannot be pinpointed to a specific location.7    Surgeons should have a high index of suspicion when evaluating these injuries. The loss of two-point discrimination is one of the first signs of compartment syndrome. With the advancement of intracompartmental pressures, the patient may have diminished or absent pulses, leading to ischemia. If one suspects compartment syndrome, proceed to measure compartment pressures. There is some variability as to when a fasciotomy is necessary. Some have recommended that pressures of 30 mmHg or more require fasciotomy while others have considered pressure 10 to 30 mmHg below diastolic pressure as an indication for fasciotomy.8-10 Surgeons should correlate the clinical picture with the pressure measurements when deciding to perform a fasciotomy.    Manoli and Weber recognized nine plantar compartments of the foot, including medial, lateral and superficial compartments that extend the entire length of the foot.11 There is also a calcaneal compartment that includes the quadratus plantae, lateral plantar nerve and, on occasion, the medial plantar nerve. This compartment has the highest pressures and the most potential for complications due to the vital structures within it. A forefoot adductor compartment and four interosseous compartments contribute the remainder of the compartments. While releasing all compartments may be necessary depending on the injury, releasing the calcaneal compartment is of the utmost importance in calcaneal fractures.

Essential Insights On Radiographic Evaluation

   Routine evaluation of calcaneal fractures should start with standard foot X-rays (AP, lateral and oblique views). We often obtain an additional calcaneal axial view. On the lateral foot view, one needs to pay attention to the crucial angle of Gissane, Böhler’s angle and the overall height of the heel bone. Joint depression fractures typically lead to a decrease in Böhler’s angle and an increase in Gissane’s crucial angle. The axial view will show the sustentacular spike and lateral displacement of the tuberosity fragment. The AP and medial oblique view of the foot will provide insight of any extension into the calcaneocuboid joint.    It is also common to obtain standard ankle X-rays. In addition to evaluating any possible ankle fracture, the mortise view frequently demonstrates fracture through the posterior facet.    The use of Broden and Isherwood views are no longer common for pre-operative evaluation. However, they do remain valuable for intraoperative evaluation. Computed tomography (CT) has become a valuable tool for meticulous evaluation of calcaneal fractures and has added a wealth of knowledge into the details of this fracture. CT scans enable surgeons to easily evaluate the number of fracture fragments, degree of comminution and the extent of articular involvement. Three-dimensional CT offers another option for additional detail. The benefit of 3-D CT is getting a more detailed description of articular anatomy and spatial relationships.12,13 Authors have suggested the 3-D CT could aid surgeons who are less familiar with calcaneal fractures and the 3-D anatomy.12    There have been various classification systems proposed for calcaneal fractures.14-17 The CT scheme proposed by Sanders, et al., has proven to be the most useful for diagnostic and prognostic utility.16 The classification is based on the fracture lines through the posterior facet as they appear on the coronal slice of the CT. Type I fractures are all non-displaced fractures. Type II fractures are two-part or split fractures. Type III fractures are three-part or split depression fractures. Type IV fractures are four-part or highly comminuted fractures.

A Guide To Effective Surgical Techniques

   The timing of surgery is critical. Typically, one would delay open reduction and internal fixation (ORIF) until five to 14 days after the injury. This eliminates concerns regarding fracture blister formation in the surgical site or wound dehiscence due to excessive swelling. Only in the face of open fractures should one consider immediate ORIF. In cases of compartment syndrome, surgeons should perform an immediate fasciotomy with subsequent ORIF at a later date when the soft tissue structures are well controlled.    When performing ORIF, one should place the patient in the lateral decubitus position with a thigh tourniquet and elevate the affected extremity. Be sure to position carefully and pad the contralateral extremity to ensure it does not obstruct the view of the affected extremity during fluoroscopy. Utilizing a lateral extensile approach, one should carry the incision directly to the lateral wall of the calcaneus. Using skin hooks, elevate the lateral flap full-thickness via subperiosteal dissection. Be careful to elevate the sural nerve and peroneal tendons within the flap. One should employ a “no touch” technique to retract the flap, placing K-wires in the tip of the fibula, talar neck and cuboid.    Proceed to identify, elevate and rotate the lateral wall fragment inferiorly. In some cases, one may place this on the back table in saline for future use. At this time, the surgeon should be able to view the primary fracture line and identify the lateral posterior facet fragment compressed in the calcaneal body. Decompress the fragment by elevating and rotating the fragment back into proximate alignment. Reduce the tuberosity to the sustentacular fragment by placing a Steinmann pin through the tuberosity. Doing so allows for distraction and medial shift of the fragment. This maneuver will re-establish the height and correct for any valgus malalignment. Proceed to place temporary fixation from the posterior tuberosity into the sustentacular fragment.    Then direct attention to the posterior facet and reduce it into proper alignment. Use K-wire fixation for temporary fixation. Subsequently, we prefer to work anteriorly and reduce the crucial angle of Gissane and the calcaneocuboid joint. In regard to the void created by the joint depression into the neutral triangle, surgeons may subsequently pack it with allograft cancellous bone chips or bone graft substitute based on their preference. The lateral wall fragment is then reduced and one can achieve fixation by using any one of the numerous calcaneal fracture plates available with small fragment sets.    Proceed to remove all temporary fixation and K-wires used for retraction and rotate the flap back into position. One may use radiographs or fluoroscopy to confirm fixation placement, reduction and proper alignment. In most cases, the surgeon would perform closure over a closed suction drain to his or her preference. Proceed to dress the extremity and place it in a posterior splint or cast boot at 90 degrees.

Pertinent Post-Op Pearls

   The advent of internal fixation has allowed early mobilization due to rigid fixation of fractures. Some surgeons recommend motion immediately after surgery.15 Others have recommended starting motion after removing the initial postoperative dressing (two weeks postoperatively).16,18,19 We recommend initiating early motion at about two weeks postoperatively or about the same time as suture removal. It is important to keep the ankle at a neutral position throughout the initial two post-op weeks in order to prevent wound healing complications with the lateral extensile flap and/or Achilles contracture.    Two weeks after the surgery, once the lateral flap demonstrates adequate healing, one can initiate aggressive range of motion. When it comes to a progression to weightbearing, we initially allow this anywhere from eight to 12 weeks after surgery, depending on the degree of comminution, radiographic consolidation and one’s comfort level with reduction and fixation.    The time needed for recovery from a calcaneal fracture is extensive. Patients can continue to make progress for 12 to 18 months after surgery. There is often a lifestyle change to some degree or another. Laborers may need to find a more sedentary type of job and certain high impact exercises may be difficult to perform. Clinicians should educate patients about this life altering injury early in the treatment process.

How To Address Common Complications

   Posttraumatic degenerative arthritis is the most common complication one sees with calcaneal fractures. This frequently leads to subsequent subtalar joint arthrodesis and/or calcaneocuboid joint arthrodesis. Researchers have reported satisfactory results in performing an isolated arthrodesis of the subtalar joint following calcaneal fractures.20    If the overall morphology of the calcaneus is not restored, the calcaneus heals in a malunited position. Nonunion of these fractures is usually not an issue as the calcaneus has a vast blood supply. Malunion results in altered mechanics of the foot and ankle. The loss of calcaneal height can result in decreased talar declination and subsequent anterior tibiotalar abutment. This often requires distraction arthrodesis of the subtalar joint to re-establish normal talar declination. There is often calcaneofibular impingement due to the loss of calcaneal height as well.    Soft tissue complications can include wound dehiscence and infection. The peroneal tendons can be damaged by impingement into the lateral gutter or disrupted by adhesions along the lateral calcaneal wall. The calcaneal fat pad is often disrupted and its shock-absorptive capabilities can be reduced. Unrecognized compartment syndromes can lead to digital deformities and chronic pain syndromes.

In Conclusion

   Managing calcaneal fractures presents a unique challenge to the foot and ankle surgeon. These fractures represent some of the more difficult musculoskeletal injuries throughout the human body. Proper management requires a detailed understanding of the pathomechanics, fracture patterns, complicating conditions and surgical techniques. A steep surgical learning curve and comorbid conditions often necessitate management by highly experienced surgeons in tertiary care centers. Even in the face of near perfect reduction and management, many patients will experience long-term sequella. Dr. Buddecke is a Diplomate with the American Board of Podiatric Surgery and is board certified in both Foot Surgery and Reconstructive Rearfoot and Ankle Surgery. He is a Fellow of the American College of Foot and Ankle Surgeons and is currently in private practice in Ottumwa, Iowa. Dr. Buddecke serves as a reviewer for the Trauma section of the Journal of Foot and Ankle Surgery. He is Adjunct Faculty at the College of Podiatric Medicine and Surgery at Des Moines University. Dr. Lee is a Diplomate with the American Board of Podiatric Surgery and is board certified in both Foot Surgery and Reconstructive Rearfoot and Ankle Surgery. He is a Fellow of the American College of Foot and Ankle Surgeons (ACFAS) and serves on the ACFAS Board of Directors. Dr. Lee is in private practice at Central Iowa Orthopaedics in Des Moines, Iowa and serves as Adjunct Faculty at the College of Podiatric Medicine and Surgery at Des Moines University. References 1. Carr JB: Mechanism and pathoanatomy of the intra-articular calcaneal fracture. Clin Orthop Rel Res 290:36-40, 1993. 2. Barei DP, Bellabarba C, Sangeorzan BJ, and Benirshke SK: Fractures of the Calcaneus. Orthop Clin North Am 33:263-285, 2002. 3. Essex-Lopresti P: The mechanism, reduction technique, and results in fractures of the os calcis. Br J Surg 39:395-415, 1952 4. Carr JB, Hamilton JJ, Bear LS: Experimental intra-articular calcaneus fractures: anatomic basis for a new classification. Foot Ankle 10:81-87, 1989. 5. Maskill JD, Bohay DR, Anderson JG: Calcaneus fractures: A review article. Foot Ankle Clinics 10:463-489, 2005. 6. Braun-Falco O: The pathoanatomy of blister formation. In Kopf AW, Andreade R (eds): The Year book of Dermatology. Chicago, Year Book Medical Publishers, 1969. 7. Myerson MS, Manol A: Compartment syndromes of the foot after calcaneal fractures. Clin Orthop Rel Res 290:142-150, 1993. 8. Bourne RB, Rorabeck CH: Compartment syndromes of the lower leg. Clin Orthop 240:97, 1989. 9. Hargens AR, Akeson WH, Mubarak SJ, et. al.: Tissue pressures: From basic research tools to clinical applications. J Orthop Res 7:902,1989. 10. Whitesides TE, Haney TC, Morimoto K, et. al.: Tissue pressure measurements as a determinant for the need of fasciotomy. Clin Orthop 113:43, 1975. 11. Manoli A, Weber TG: Fasciotomy of the foot: An anatomical study with special reference to release of the calcaneal compartment. Foot Ankle Int 10:267-275, 1990. 12. Prasartritha T, Sethavanitch C: Three-dimensional and two-dimensional computerized tomographic demonstration of calcaneus fractures. Foot Ankle Int. 25:262-273, 2004. 13. Freud M, Hohendroft B, Zenker W, Hutzelmann A: The CT of calcaneal fractures: 3-D reconstructions with electronic disarticulation. ROEFO 164:189-195, 1996. 14. Crosby LA, Fitzgibbons T: Computerized tomography scanning of acute intra-articular fractures of the calcaneus. A new classification system. J Bone Joint Surg 72:852-859, 1990. 15. Zwipp H, Tscherne H, Thermann H, et. al.: Osteosynthesis of displaced intra-articular fractures of the calcaneus. Results in 123 cases. Clin Orthop Rel Res 290:76-86, 1993. 16. Sanders R, Fortin P, DiPasquale A, et. al.: Operative treatment in 120 displaced intr-articular calcaneal fractures. Results using a prognostic computed tomographic scan classification. Clin Orthop Rel Res 290:87-95. 17. Bohler L: Diagnosis, pathology, and treatment of fractures of the os calcis. J Bone Joint Surg 13:75-89, 1931. 18. Benirshke SK, Sangeorzan BJ, Hansen ST: Results of operative treatment of calcaneal fractures of the foot. Surgical management of calcaneal fractures. Clin Orthop Rel Res 292:128-134, 1993. 19. Thordarson DB, Krieger LE: Operative vs. nonoperative treatment of intra-articular fractures of the calcaneus: a prospective randomized trial. Foot Ankle Int 17:2-9, 1996. 20. Carr JB, Hansen ST, Benirshke SK: Subtalar distraction bone block fusion for late complications of os calcis fractures. Foot Ankle Int 9:81, 1988. For related articles, see “Clearing Up The Confusion Over Posterior Calcaneal Pain” in the October 2000 issue of Podiatry Today or “How To Perform The Double Calcaneal Osteotomy” in the December 2004 issue. Also be sure to check out the archives at www.podiatrytoday.com.
 

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CE Exam #136 Choose the single best response to each question listed below: 1. Which of the following is the clear gold standard for managing calcaneal fractures? a) Cast immobilization b) Percutaneous pinning c) Fine wire external fixation d) None of the above 2. Which of the following statements is false about the neutral triangle? a) It is an area relatively void of trabecular patterns. b) It is directly under Gissane’s crucial angle. c) It lies directly over top of the lateral process of the talus. d) None of the above 3. In regard to the primary fracture line in calcaneal fractures … a) It will exit laterally above the lateral talar process or extend anteriorly without involving the calcaneocuboid joint. b) An inverted foot will cause the fracture line to begin more medially. c) An everted foot will cause the fracture line to begin more medially. d) a and b 4. Which is not a possible sign of compartment syndrome? a) Severe, burning pain that is commonly found in the first MPJ b) The loss of two-point discrimination c) Severe, burning pain that cannot be pinpointed to a specific location d) All of the above 5. In regard to the measurement of compartment pressures, when is a fasciotomy indicated? a) In the literature, some recommend it when pressures are 30 mmHg or greater. b) In the literature, some recommend it when pressures are 10 to 30 mmHg below diastolic pressure. c) The authors recommend correlating the clinical picture with pressure measurements when considering a fasciotomy. d) All of the above 6. When it comes to the _______ X-ray view of a calcaneal fracture, one should pay attention to the crucial angle of Gissane, Bohler’s angle and the overall height of the heel bone. a) Lateral b) AP c) Oblique d) None of the above 7. Which of the following imaging views offers a more detailed description of articular anatomy and spatial relationships? a) AP X-ray view b) Three-dimensional CT c) Oblique X-ray view d) Broden view 8. Under the CT classification scheme for calcaneal fractures proposed by Sanders, et. al., Type II fractures are: a) Split depression fractures b) Highly comminuted fractures c) Split fractures d) Non-displaced fractures 9. In regard to the timing of surgery for calcaneal fractures, one would typically delay open reduction and internal fixation (ORIF) until … a) Three weeks after the injury b) One month after the injury c) Five to 14 days after the injury d) Two to four days after the injury 10. In the authors’ experience, what is the most common complication with calcaneal fractures? a) Posttraumatic degenerative arthritis b) Nonunion c) Malunion d) Soft tissue complications Instructions for Submitting Exams Fill out the enclosed card that appears on the following page or fax the form to NACCME at (610) 560-0502. Within 60 days, you will be advised that you have passed or failed the exam. A score of 70 percent or above will comprise a passing grade. A certificate will be awarded to participants who successfully complete the exam. Responses will be accepted up to 12 months from the publication date.