**3. Risk factor**

At this moment, we are able to classify risk factors, related to the establishment of non-union, in two big groups: factors proper of the patient at the moment of injury and characteristics of the trauma itself.

Between general risk factors, we can found advanced age (especially in female population penalized by hormonal imbalances resulting from the menopause); non-compensated diabetes (besides the well-known vascular and nervous disorders, it was observed a decrease in the formation of collagen and cells involved in bone callus formation and maturation); osteopo‐ rosis; muscle atrophy; lifestyle (food, smoke, alcohol); drugs as NSAD, often prescribed against pain after surgery (the reason of their bad influence on healing time is to be found in decreased macrophagic activity and prostaglandin synthesis induced by COX 1 and 2 inhibition) [8].

Local risk factors, that are inherent to the trauma itself, include


anatomic reduction of fragments with the intent to preserve vascularization is a positive prognostic factor.

Tibial pilon fractures are mainly caused by high-energy trauma. This kind of dynamic determines not only more serious damage to the bone, but often cause damage of the sur‐ rounding tissues.

Following important lesions of the periosteum and of the vascular network and after a suboptimal synthesis caused by comminution and dislocation of fragments is frequent with the evolution toward a bad bone healing process.

After the end of the 1980s, thanks to statistic analysis proposed by authors as McFerran [3] and Dillin [12] and, more recently Piper et al. [13], it was possible to clarify the importance of risk factors that affect the prognosis of tibial pilon fractures.

Distal tibia is characterized by a relatively poor vascularization and skin coverage. These structures, when seriously damaged from the mechanism of injury, penalize the healing of fractures.

There are several factors to whom was charged complicity in the development of such an eventuality; among the most important, we find:


Its, however, not negligible the eventuality that fractures of patients treated correctly, and with low-risk rate, could evolve toward non-union.

It seems that the population of patients affected by non-union is somehow selected toward those patients that present a higher risk of this complication. For this reason, it seems even more important to analyze and classify these patients to define better surgical program and even in some way to clarify the risk of treatment failure.

Is not a rare observation that some subject, unfortunately few in number, even if treated not correctly shows "miraculous healing." Instead, is greater the number of patients that, although treated in a good way, under go several in effective surgical procedures.
