Cutting Edge Orthopedics - Issue 3

2 • CUTTING EDGE - ORTHOPEDICS involvement. Injuries to the ankle involve more than just the boney structures. The bone around the ankle is generally subcutaneous and often has poor soft tissue coverage. Thus, due to these characteristics, fractures about the ankle, unfortunately, often have significant associated soft tissue injuries. Perhaps the most important variable, and the least predictable, is the host. The medical and social history of the patient and his compliance can have a major effect on the success or failure of the treatment plan. A successful outcome requires a balance between the stability of the fracture treatment construct and the biological viability of the fracture site. Unlike muscle, cartilage, and other connective tissue, bone does not heal with scar tissue. It is one of the few tissues in the body that heals with the same material—bone. Fractures, osteoto- mies, and arthrodesis constructs are thus repaired by a process of boney regeneration. A boney union is one that is repaired to the degree that it is mechanically able to function like denovo bone. The patient experiences no pain, and there is clinical stability at the fracture site. Clinical frac- ture unions are accompanied by radiographic signs of healing. In order to confirm a true union, both radiographic and clinical signs should be present. A delayed union is a fracture that, though making continual progress toward union, has not healed in the usual amount of time for a similar fracture. A nonunion is a fracture that will not heal. It has sustained an arrest of the repair process and has not shown radiographic or clinical progress toward healing for months. Nonunions may have some clinical stability, as they will have cartilage or fibrous interposition instead of bone. Others will be atrophic, with little healing tissue, and have no clinical stability. Though nonunions cannot be predicted, some fractures are destined to go on to nonunion from the beginning of treatment. Determination of Delayed or True Nonunion The first issue in treatment is determining whether the fracture is merely delayed or a true nonun- ion [3]. A delayed union may go on to a successful outcome if given more time, while a true non- union will require intervention to achieve union. This is not a trivial question to answer for the patient. Though most nonunions will be diagnosed if the surgeon waits long enough, it is impera- tive to identify fractures that are falling behind as soon as possible in order to shorten overall treatment time and to restore the patient back to full function. Government payers and many private insurance companies subscribe to clinical guidelines that incorporate a time factor into the definition of a nonunion. The United States Food and Drug Administration defines a nonunion as being “established when a minimum of nine months has elapsed since injury and the fracture site shows no visibly progressive signs of healing for a minimum of three months” [4]. This definition is not pragmatic and leads to prolonged morbidity, long periods of work-related impairment or socioeconomic stress, and the potential for narcotic abuse. As surgeons, we know that there are injuries that are at risk for nonunion based on the injury (open fracture, comminution, or bone loss), anatomic location (distal tibia and 5th metatarsal), or host (diabetic, smoker, and cancer patient). It has thus become more acceptable to label fractures as delayed or nonunions when the surgeon believes the fracture has little or no ability to heal. Delaying intervention for an arbitrary length of time before calling a fracture a nonunion results in more disability, more time off work,