Outcomes of Sanders Type IV Calcaneal Fractures Treated With Open Reduction and Internal Fixation (ORIF) Plus Primary Subtalar Arthrodesis (PSTA) Versus Conservative Management Then Calcaneoplasty and Late Subtalar Arthrodesis.

Fracture calcaneus accounts for up to 2% of all fractures. 75% of calcaneal fractures are displaced intra-articular fractures and historically have been associated with poor functional outcomes.

When the talus applies an axial loading to the posterior facet, shear forces result in a primary fracture line between medial (sustentaculum tali) and lateral part of the calcaneus. As the axial force continues, a secondary fracture line will develop. According to the relation of the secondary fracture line's exit to insertion of tendo-achilis Essex-Lopresti classified that into two types joint depression and tongue.

Numerous classifications exist in the literature but that by Sanders is the most prevalent and best suited for clinical practice and for research purposes.

Sanders in his clinical trials found that as the number of articular fragments- based on axial and coronal CT scan cuts with the widest undersurface of the posterior facet of the talus- increase, the results and prognosis worsen.

Up to 73% in the sanders type IV fractures eventually leads to subtalar fusion to manage post-traumatic subtalar arthritis. They are 5.5 times more likely to require subtalar arthrodesis than Sanders II fractures. Second surgeries increase the cost of management and delay the return of level of function for the patient.

Some authors advocate that the fractures with a higher Sanders classification demonstrated no difference between operative and non-operative treatment. However, careful stratification of the patients may show better outcomes after surgical intervention in some groups.

There is no consensus about how to manage calcaneal fractures but we can divide management into four broad categories: Non-operative, Open reduction and internal fixation, Minimally invasive reduction and fixation and finally Primary ORIF and subtalar arthrodesis.

Our trial was conducted to add to the current evidence and our main questions are: does initial reduction and fixation of comminuted displaced intra-articular Sanders type IV calcaneal fractures matter in subtalar fusion?