Summary Calcaneus fractures are the most common fractured tarsal bone and are associated with a high degree of morbidity and disability. Diagnosis is made radiographically with foot radiographs with CT scan often being required for surgical planning. Treatment is nonoperative versus operative based on fracture displacement and alignment, associated soft tissue injury, and patient risk factors. Epidemiology Incidence common most frequent tarsal fracture 60-75% of injuries are intra-articular fractures 1-3% are calcaneal tuberosity fractures Anatomic location 17% are open fractures no significant increase in infection rates increased risk for wound complications calcaneal tuberosity fractures peak incidence in women in seventh decade of life Etiology Pathophysiology mechanism intra-articular fractures traumatic axial loading is the primary mechanism of injury fall from height motor-vehicle accidents calcaneal tuberosity fractures poor bone quality/osteoporosis violent contaction of the triceps surae with forced dorsiflexion strong concentric contaction of the triceps surae with knee in full extension intrinsic tightness of the gastrocnemius and achilles tendon peripheral neuropathy leading to decreased pain sensation and proprioception resulting in recurrent microtrauma calcaneal stress fractures increased physical activity in the setting of relative energy deficiency anterior process fractures twisting injury mechanism avulsion injury of the bifurcate ligament pathoanatomy intra-articular fractures primary fracture line results from oblique shear and leads to the following two primary fragments superomedial fragment (constant fragment) includes the sustentaculum tali and is stabilized by strong ligamentous and capsular attachments superolateral fragment includes an intra-articular aspect through the posterior facet secondary fracture lines dictate whether there is joint depression or tongue-type fracture extra-articular fractures strong contraction of gastrocnemius-soleus with concomitant avulsion at its insertion site on calcaneus more common in osteopenic/osteoporotic bone anterior process fractures inversion and plantar flexion of the foot cause avulsion of the bifurcate ligament Associated injuries orthopaedic extension into the calcaneocuboid joint occurs in 63% vertebral injuries in 10% contralateral calcaneus in 10% Anatomy Osteology articular facets superolateral fragment contains the articular facets superior articular surface contains three facets that articulate with the talus posterior facet is the largest and is the major weight bearing surface the flexor hallucis longus tendon is medial to the posterior facet and inferior to the medial facet and can be injured with errant drills/screws that are too long middle facet is anteromedial on sustentaculum tali anterior facet is often confluent with middle facet sinus tarsi between the middle and posterior facets lies the interosseous sulcus (calcaneal groove) that together with the talar sulcus makes up the sinus tarsi sustentaculum tali projects medially and supports the neck of talus FHL passes beneath it represented by the constant fragment deltoid and talocalcaneal ligament connect it to the talus contained in the anteromedial fragment, which remains "constant" due to medial talocalcaneal and interosseous ligaments bifurcate ligament connects the dorsal aspect of the anterior process to the cuboid and navicular Classification Extra-articular (25%) avulsion injury of anterior process by bifurcate ligament sustentaculum tali calcaneal tuberosity (Achilles tendon avulsion) Intra-articular (75%) Essex-Lopresti classification the primary fracture line runs obliquely through the posterior facet forming two fragments the secondary fracture line runs in one of two planes the axial plane beneath the facet exiting posteriorly in tongue-type fractures when the superolateral fragment and posterior facet remain attached to the tuberosity posteriorly behind the posterior facet in joint depression fractures Sanders classification based on the number of articular fragments seen on the coronal CT image at the widest point of the posterior facet Sanders classification Type I Nondisplaced posterior facet (regardless of number of fracture lines) Type II One fracture line in the posterior facet (two fragments) Type III Two fracture lines in the posterior facet (three fragments) Type IV Comminuted with more than three fracture lines in the posterior facet (four or more fragments) Beavis classification based on fracture morphology of the calcaneus tuberosity Beavis Classification (based on fracture of tuberosity) Type 1 Sleeve fracture - small shell of cortical bone avulses from the tuberosity Type 2 Beak fracture - oblique fracture line runs posteriorly from most superior portion of the posterior facet Type 3 Infrabursal fracture from the middle of the tuberosity Presentation Symptoms pain swelling inability to bear weight gross deformity open fracture Physical exam inspection ecchymosis and swelling shortened and widened heel may have apparent varus deformity open skin lesions or fractures posterior heel skin compromise tenting, ecchymosis, or lack of skin blanching with tuberosity fractures neccessitates urgent sugical reduction and fixation to avoid posterior heel skin necrosis fracture blisters must be debrided and epithelialized prior to surgical intervention palpation diffuse tenderness to palpation lack of heel cord continuity in avulsion fractures lack of posterior heel skin blanching with tenting fractures assess for compartment syndrome secondary to swelling rare presence of Langer's lines and skin wrinkles suggests skin is appropriate for surgical intervention strength decreased ankle plantarflexion strength with avulsion fractures neurologic assess for neuologic compromise due to swelling vascular assess peripheral pulses severe peripheral vascular disease may preclude surgical treatment due to poor wound healing potential Imaging Radiographs recommended views AP lateral oblique optional views Broden allows visualization of posterior facet useful for evaluation of intraoperative reduction of posterior facet with ankle in neutral dorsiflexion and ~45 degrees internal rotation, take x-rays at 40, 30, 20, and 10 degrees cephalad from neutral Harris visualizes tuberosity fragment widening, shortening, and varus positioning place the foot in maximal dorsiflexion and angle the x-ray beam 45 degrees AP ankle demonstrates lateral wall extrusion causing fibular impingement findings double-density sign represents subtalar incongruity indicates partial separation of facet from sustentaculum lateral portion of the posterior facet calcaneal shortening varus tuberosity deformity decreased Böhler's angle angle between line from highest point of anterior process to highest point of posterior facet + line tangential to superior edge of tuberosity measured on lateral view normal 20-40° represents collapse of the posterior facet increased angle of Gissane angle between line along lateral margin of posterior facet + line anterior to beak of calcaneus measured on lateral view normal 120-145° represents collapse of the posterior facet CT indications gold standard should perform 2-3 mm cuts views 30-degree semicoronal demonstrates posterior and middle facet displacement axial demonstrates calcaneocuboid joint involvement sagittal demonstrates tuberosity displacement MRI indications used only to diagnose calcaneal stress fractures in the presence of normal radiographs and/or uncertain diagnosis Treatment Nonoperative cast immobilization with nonweightbearing for 6 weeks indications calcaneal stress fractures cast immobilization with nonweightbearing for 10 to 12 weeks indications small extra-articular fracture (<1 cm) with intact Achilles tendon and <2 mm displacement Sanders Type I (nondisplaced) near normal Böhler's angles (20-40°) anterior process fracture involving <25% of calcaneocuboid joint comorbidities that preclude good surgical outcome (smoker, diabetes, PVD) avoids the high wound complications seen with these fractures minimally displaced tuberosity fractures (<1 cm of displacement) without threatened soft-tissue envelope in elderly patients with reduced function or physical capacity techniques begin early range of motion exercises once swelling allows Operative closed reduction with percutaneous pinning indications minimally displaced tongue-type fxs or those with mild shortening large extra-articular fractures (>1 cm) early reduction prevents skin sloughing and need for subsequent flap coverage ideal in patients with sever peripheral vascular disease or severe soft-tissue compromise techniques lag screws from posterior superior tuberosity directed inferior and distal ORIF indications displaced tongue-type fractures >1 cm displacement threatened soft tissue require urgent reduction and fixation to avoid skin necrosis (disastrous consequence) open fractures open reduction allows for sufficient debridement of contaminated tissue inability to participate in closed treatment large extra-articular > 2 mm displacement Sanders Type II and III posterior facet displacement >2 to 3 mm, flattening of Bohler angle, or varus malalignment of the tuberosity anterior process fracture with >25% involvement of calcaneocuboid joint displaced sustentaculum fractures timing wait 10-14 days until swelling and blisters resolve and wrinkle sign present 10-14 days no benefit to early surgery due to significant soft tissue swelling displaced tuberosity fractures with posterior skin compromise should be addressed urgently outcomes surgical outcome correlates with the number of intra-articular fragments and the quality of articular reduction surgical treatment decreases the risk of post-traumatic arthritis factors associated with a poor outcome age > 50 (similar outcomes with surgical and nonsurgical treatment) obesity initial Böhler's angle <0° (these injuries do poorly regardless of treatment) lower Böhler angles suggest greater energy absorbed manual labor open fractures (significant soft tissue injury and engery absorbed) workers comp smokers (poor wound healing) bilateral calcaneal fractures (significant gait problems following bilateral injuries) multiple trauma vasculopathies men do worse with surgery than women factors associated with most likely need for a secondary subtalar fusion male worker's compensation patient who participates in heavy labor work with an initial Böhler angle less than 0 degrees primary subtalar arthrodesis indications Sanders Type IV techniques combined with ORIF to restore height Techniques Cast immobilization with nonweightbearing for 6 weeks techniques: standard short-leg cast for calcaneal stress fractures nonweight bearing cast well-padded heel Cast immobilization with nonweightbearing for 10-12 weeks techniques: standard short-leg cast applied with mild equinus windowed over posterior heel to allow for frequent skin checks requires close follow-up to determine if pull of gastrocnemius-soleus dispaces fracture weekly cast changes are necessary due to high incidence of skin complications high incidence of vascular insufficiency and diabetes in this population Closed reduction and percutaneous pinning ideal for poor soft tissue coverage or patients with peripheral vascular disease techniques: Steinmann pin placed into the fracture site anteromedially-to-posterolateral to leverage fragments into place additional K-wires and Steinmann pins are placed from posterior-to-anterior and lateral-to-medial to secure remaining bone fragments calcaneal transfixin pin can be used to distract fracture percutaneus tamps and elevators can be used to raise the articular surface pins are cut flush with the skin and removed 8-10 weeks post-op can be combined with distracting external fixator pins placed in calcaneal tuberosity, cuboid, and distal tibia restor calcaneal height, width, and alignment can be combined with percutaneous cannulated screws ORIF extensile lateral or medial approach techniques: extensile lateral L-shaped incision is most popular vertical portion inbetween posterio fibula and achilles tendon horizontal portion in line with 5th metatarsal base a more inferior incision protects the sural nerve high rate of wound complications provides access to the calcaneocuboid and subtalar joints full-thickness skin, soft tissue, and periosteal flaps are developed flap supplied by lateral calcaneal branch of peroneal artery superior flap contains the calcaneofibular ligaments and peroneal tendon sheath sural nerve and peroneal tendons are retracted superiorly lateral calcaneal wall visualized fracture opened and medial wall reduced going medial to lateral reduction confirmed indirectly via fluoroscopy tuberosity reduction is done under direct visualization manual traction, Schanz pins, and minidistractors pin in tuberosity aids with reduction height and length of tuberosity is recreated quality of reduction affects outcomes provisional fixtaion was K-wires definitive fixation with plates and screws bone grafting provided no added benefit goals: restore congruity of subtalar joint restore Böhler's angle and calcaneal height restore width correct varus malalignment sinus tarsi approach minimally invasive incision that minimizes soft tissue dissesction reduces wound complications associated with extensile lateral incision allows direct visualization of the posterior facet, anterolateral fragment, and lateral wall lower incidence of sural nerve neuralgia same incision can be utilized for secondary subtalar arthrodesis or peroneal tendon debridement decreased surgical time techniques: patient placed in lateral decubitus position incision made in line with the tip of the fibula and the base of the 4th metatarsal 2-4 cm in length extensor digitorum brevis retracted cephalad to expose sinus tarsi and posterior facet peroneal tendons retracted posteriorly Schanz pin inserted percutaneously in posteroinferior tuberosity going from lateral to medial provides distraction and aids with reduction fibrous debris and fat removed from sinus tarsi small elevator or lamina spreader placed under posterior facet fragment to aid in reduction K-wires inserted for provisional fixation aimed towards the sustentaculum two screw are placed lateral-to-medial to engage sustentaculum and support facet one large fully threaded screw from posterior-to-anterior to support axial length of calcaneus low-profile plate is applied underneath a well developed soft tissue envelope with screws engaging anterolateral and tuberosity fragments nonweight bearing for 6-8 weeks post-op with ankle range-of-motion exercises beginning 2 weeks post-op Essex-Lopresti manuever manipulate the heel to increase the calcaneal varus deformity plantarflex the forefoot manipulate the heel to correct the varus deformity with a valgus reduction stabilize the reduction with percutaneous K-wires or open fixation as described above arthroscopic-assisted reduction and internal fixation benefits: decreased soft-tissue dissection preservation of local blood supply removal of loose bone fragments improved visualization of articular surface and carilage lesions cons: increased set-up increased swelling from fluid extravasation technically challenging can be combined with sinus tarsi approach technqiues: patient positioned in lateral decubitus position fluoroscopy unit positioned posterior and oblique to patient allows for axial hindfoot views anterolateral and posterolateral portals are used to visualize posterior facet 2.4 mm 0° arthroscope interosseous ligament is preserved hematoma is irrigated loose bodies and cartilage fragments are removed with a shaver Freer elevator is introduced into one of the portal sites and used to elevate the posterior facet reduction can be visualized directly Schanz pin to control tuberosity fragment cannulated screws from the posterior aspect of the calcaneal tuberosity to the anterior aspect of the calcaneus restores and stabilizes length lateral-to-medial screws placed in sustentaculum buttress screw from the posterior aspect of the calcaneal tuberosity to the subchondral bone of the posterior facet posterior approach for calcaneal tuberosity fractures techniques: patient positioned prone on table posterior midline incision fracture fragment is mobilized and debrided plantar flexion of foot aids with reduction presence of gastrocnemius tightness may preclude reduction Strayer procedure may be performed to aid in reduction provisional fixation with K-wires final fixation with either lag screws tension-band constructs figure-of-8 tension-band wire passed around ends of K-wires or cannulated screws suture fixation Krackow sutures passing through bone tunnels restricted weight bearing for 6 weeks followed by progression of weight bearing an additional 6 weeks Primary subtalar arthrodesis performed in highly comminuted Sanders IV intraarticular fractures high rate of secondary fusion after ORIF with these injuries avoids added treatment costs and decreases time off from work techniques: can be performed through an extensile lateral or sinus tarsi approach fracture reduction is perfromed in a similar fashion as ORIF articular cartilage of the subtalar joint denuded to bleeding subchondral bone cannulated compression screws are placed from the posterio calcaneal tuberosity to the talar dome lateral fixation plate applied to hold reduction Complications Wound complications (10-25%) increased risk in smokers, diabetics, and open injuries may consider nonoperative treatment in these patients tongue type fractures at high risk (>20%) for posterior skin necrosis should be splinted in 30 degrees of planarflexion to relieve soft tissue tension keep all hardware away from the corner of the incision delayed wound healing is the most common complication Subtalar arthritis increased with nonoperative management can be addressed with ankle bracing (gauntlet type), NSAIDs, injections, and physical therapy may require bone block subtalar arthrodesis to address loss of calcaneal height important when there are symptoms of anterior ankle impingement in-situ arthrodesis with preserved calcaneal height Lateral impingement with peroneal irritation Sural nerve neuroma Damaged FHL at risk with placement of lateral to medial screws, especially at level of sustentaculum tali (constant fragment) Compartment syndrome (10%) results in claw toes Malunion introduction loss of height, widening, and lateral impingement physical exam limited ankle dorsiflexion due to dorsiflexed talus with talar declination angle <20 classification (see below) treatment distraction bone block subtalar arthrodesis indications chronic pain from subtalar joint incongruous subtalar joint/post-traumatic DJD loss of calcaneal height mechanical block to ankle dorsiflexion results from posterior talar collapse into the posterior calcaneus technique goal is to correct hindfoot height ankle impingement subfibular impingement subtalar arthritis Malunion CT Classification & Treatment Type I Lateral exostosis with no subtalar arthritis Treat with lateral wall resection Type II Lateral exostosis with subtalar arthritis Treat with lateral wall resection and subtalar fusion Type III Lateral exostosis, subtalar arthritis, and varus malunion Treat with lateral wall resection, subtalar fusion, and +/- valgus osteotomy (controversial) Prognosis Poor with 40% complication rate increased due to mechanism (fall from height), smoking, and early surgery lateral soft tissue trauma increases the rate of complication