**9. Complications**

Calcaneus fractures are prone to many complications based on the high-energy nature of these injuries and the calcaneus's thin, soft tissue envelope and anatomic relationship to many soft-tissue structures. Predominant complications consist of post-traumatic arthritis and wound-healing issues. Up to 37 and 20% of operations utilizing the extended L-shaped lateral incision have wound difficulties [50].

Long-term follow-up indicates that patients who undergo fixation of Sanders type III fractures are four times more likely to require subtalar arthrodesis compared to those with type II fractures [43]. This can be attributed to both the difficulty associated with treating these fractures and a testament to the overall high-energy mechanism responsible for most of these fractures. Inadequate articular reduction of the posterior facet can result in progressive loss of the joint [77]. Furthermore, subtalar arthritis can arise even with an anatomic articular reduction due to the chondrocyte damage sustained during the initial injury [77, 78]. Management of post-traumatic arthritis begins with conservative treatments similar to other joints. Over-the-counter anti-inflammatories, shoe-wear modification, bracing, activity modification, and other conservative modalities are first attempted. As conservative management fails, surgical options to be explored involve arthrodesis of the subtalar joint and other joints affected with post-traumatic arthritis.

Wound-healing problems represent one of the most common complications following surgical treatment of calcaneus fractures, with reports citing complication rates up to 25% [79–81]. The strongest risk factors for wound breakdown include diabetes, smoking, increasing Sanders type, and open fracture [79, 80]. Management of wound complications initially involves oral antibiotic therapy with local wound care for minor wounds. As the size of the wound increases beyond minor dehiscence, operative intervention is required, utilizing increasing levels of surgical debridement and soft-tissue reconstruction. Cavadas et al. propose an algorithm of soft-tissue management in calcaneal fractures utilizing a local subcutaneous transverse flap, a sural subcutaneous flap, and a distal vastus lateralis free flap, depending on the wound severity and patient factors [82]. The study defined minor wounds as <1.5 cm, moderate as 1.5–5 cm, and extensive as >5 cm. All wounds and fractures healed in the study [82]. Furthermore, Krishna et al. provide an algorithm for treating heel wounds utilizing wound location and weight-bearing status as a guide for soft-tissue reconstruction selection [83]. Local rotation and advancement flaps were very useful for small defects. Moderate anterior heel defects were treated with a medial plantar artery flap, and complete defects were treated with an extended reverse sural flap. The islanded reverse sural flap was utilized for posterior heel defects [83].

Additionally, neurologic injury is a common complication experienced in calcaneal fractures. When utilizing an extensile lateral approach, the most common injury involves the sural nerve, specifically the sensory cutaneous nerve [77, 84]. With a medial approach, the tibial nerve is at risk, with the calcaneal branch being most at risk [84, 85]. Management of this injury initially involves medications, including gabapentin, shoe inserts to accommodate the area of injury, and physical therapy [77, 84]. When there is failure of conservative management of the nerve injury, operative neurolysis and burying of the nerve into deeper tissue can be employed [77, 85, 86]. Regarding nonsurgical treatment of calcaneal fractures, posterior tibial nerve entrapment is the most common neurologic complication [77]. Treatment of this entrapment involves the treatment pathway of nerve compression with conservative management initiated first, followed by surgical decompression if necessary.

#### *Calcaneus Fractures DOI: http://dx.doi.org/10.5772/intechopen.114132*

Malunion of calcaneal fractures is a well-documented complication. Consequences of malunion include but are not limited to: increased heel width, subfibular impingement, tibiotalar impingement, varus/valgus deformity at the hindfoot, peroneal tendon dysfunction, and subtalar arthrosis [77, 86, 87]. For isolated lateral impingement symptoms, lateral wall decompression can provide good results. However, more complex deformities require further operative planning and management [87].

Flexor hallucis longus pathology remains another complication worth noting. Damage to the FHL tendon can occur due to displaced fracture and misplaced screws into the sustentaculum tali during reconstruction. Misplaced screws can penetrate the opposite cortex inferior at the sustentaculum tali and directly impinge on the FHL tendon [88]. Treatment involves screw removal and replacement in this setting.
