**6. The NUSS**

In the new NUSS classification of 2008 are considered all the variables and all risk factors, giving to anyone a score based on clinical experience and scientific evidences and defining so a treatment guideline depending from the final score [17].

The final score, obtained by the sum of the individual score, allows to compare different patients with different non-union, making them objectively comparable according to a principle of complexity.

Atrophic forms of non-union can have better prognosis and greater chance of healing than oligotrophic reactive forms, in patients affected by impaired general health condition, as in example a non-compensated diabetes.
