Fracture nonunion classification
Fracture non-unions can be classified in a couple of ways. Calori et al have created a Non-Union Scoring System (NUSS) that can address severity to help further management and research. This system evaluates 16 different aspects, including not only a bone quality, but also a soft tissue status, surgical fixation factors and patient health comorbidities. The results are divided in 4 grades of non-union, where each grade reflexes a management complexity. Another classification was suggested by Weber-Cech. It divides non-unions based on Xray features and vascularity of the fracture site into 3 groups. Hypertrophic variant is described as abundant callus formation with bulging of the fracture margins. The vascularity in such cases is not an issue, thus it only requires a better mechanical stability to progress to union. On the other hand, atrophic non-unions demonstrate a poor vascularity of the fracture margins and lack of callus formation. Resorption of bone at the fracture site and fibrous capsule are commonly seen in this variant. The last group are oligotrophic non-unions which have a proper vascularisation but poor to no callus formation. More details by the link!