Principles and Evaluation of Bony Unions

Nonunion has devastating impacts on patients recovering from fusion and fracture. Nonunion patients report lower health-related quality of life scores than patients with type-1 diabetes, stroke, and HIV. With particular interest for upper extremity surgeons, nonunions of the forearm had the worst self-reported utility scores of all bones measured.57 An overwhelming majority of fractures go onto bony union without difficulty. There are, however, high-risk features that can greatly influence the rate and time course of healing. Without a clear, universally agreed-upon definition, identifying a nonunion is a diagnostic challenge. Currently, most nonunions are diagnosed by a I know it when I see it philosophy. One point of agreement is that a nonunion, in the absence of metabolic derangement, will not heal without further surgical intervention. It would, therefore, be helpful to have widely agreed-upon guidelines for the diagnosis of nonunion that are specific to certain fractures, especially those that have a higher propensity to develop nonunion.Further study is necessary to quickly identify fractures that are developing nonunion as well as research on better management strategies. It is clear that certain patients are at higher risk for the development of nonunion than others; however, it is still very much a waiting game. With recent advances in large-scale data analytics, the goal is to be able to more accurately predict incipient nonunions, allowing for quicker action. Advances in big data, combined with validated radiographic nonunion scoring systems, can help to quickly and accurately identify nonunions. Additionally, more studies on advanced imaging modalities to detect poor blood flow as well as evidence of infection are needed. Newer MRI technology, ad-vances in ultrasound techniques, and nuclear medicine modalities may all prove to be beneficial to evaluating bony healing or identifying features at high risk for developing nonunion.Identifying a nonunion is only part of the picture. Further research is needed on how to prevent nonunion at the index surgery or when managing fractures nonoperatively. Either through improved surgical techniques to promote bony healing or reduce the risk of infection, or through modifying patient-related risk factors, identifying interventions that minimize the rate of nonunion is paramount. Additionally, when we do identify nonunion, we need to have better tools and techniques to manage it. Future areas of research for the management of nonunion include biologic augmentation through growth factors and refining bone grafting techniques. Additionally, there may be a future role of nonoperative treatment through medical management due to newer understandings of the complex cellular interactions of bone healing.Upper extremity-specific nonunion research is needed. Much of the research on nonunion is focused on lower extremity, especially tibia fractures. While many of the principles are the same, it is important to validate management strategies and tailor them to the unique anatomy and mechanical environment of the upper extremity.

Automated summary

Nonunion has devastating impacts on patients recovering from fusion and fracture. Further research is needed to prevent and manage nonunion, with a specific focus on upper extremity cases.