A wide range of different classifications exist for distal radius fractures (DRF). Most of them are based on plane X-rays and do not give us any information on how to treat these fractures. A biomechanical understanding of the mechanical forces underlying each fracture type is important to treat each injury specifically and ensure the optimal choice for stabilization. The main cause of DRFs are forces acting on the carpus and the radius as well as the position of the wrist in relation to the radius. Reconstructing the mechanism of the injury gives insight into which structures are involved, such as ruptured ligaments, bone fragments as well as the dislocated osteoligamentous units. This article attempts to define certain key fragments, which seem crucial to reduce and stabilize each type of DRF. Once the definition is established, an ideal implant can be selected to sufficiently maintain reduction of these key fragments. Additionally, the perfect approach is selected. By applying the following principles, the surgeon may be assisted in choosing the ideal form of treatment approach and implant selection.
Herbert's classification of scaphoid fractures provides the underlying rationale for treatment according to the fracture type. A CT bone scan in the long axis of the scaphoid is the best means of differentiating between stable and unstable fractures. This is difficult from conventional X-rays due to the particular three-dimensional anatomy of the scaphoid. To avoid long-term plaster immobilization and to diminish the risk of a nonunion, unstable fractures of type B should be fixed operatively. With headless screws such as the Herbert screw, which are now available in a cannulated shape, the majority of scaphoid fractures of type B1 and B2 can be stabilized using minimally invasive procedures. Severely displaced fractures require the classical open palmar approach. Proximal pole fractures (B3) are best managed from the dorsal approach, using the Mini-Herbert screw. Stable fractures of type A2 can be treated conservatively in a below-elbow cast or, alternatively, stabilized percutaneously, which allows early mobilization.
We have established a simple method of measuring joint motion under physiological conditions. For this purpose we use an ultrasound measuring system employing marker points consisting of miniaturized ultrasound transmitters. This device was tested on a simple biomechanical model, the linkage of the proximal and distal interphalangeal joints. The angles of these joints were recorded during opening and closing of the fist in 34 index fingers of 17 healthy persons. The results of the measurements were plotted on a rectangular coordinate system. Analysis showed an approximately linear linkage between the IP joints of the index finger. The curve for extension was the same as that for flexion. The linkage varies greatly. On average 1 degree of PIP joint flexion is equivalent to 0.76 degree of DIP joint flexion. Our study showed no significant difference between the dominant and non-dominant hand. The results showed that there is a linear linkage between the proximal and distal interphalangeal joints, which is equal for flexion and extension.
It is my belief that all acute proximal pole fractures should be treated by open reduction and internal fixation, via a dorsal approach. There is no longer any place for conservative treatment of these fractures, because a lengthy period of plaster immobilization is required and there is an unacceptably high risk of nonunion with conservative management. Unfortunately, nonunion of the proximal pole remains a common and disabling problem which demands careful evaluation and treatment. Internal fixation combined with limited cancellous bone grafting produces very satisfactory results in terms of pain relief and function, and clinical results are as good as those reported for more complex procedures involving vascularized grafts and prolonged cast immobilization. While the place for vascularized grafting has yet to be clearly defined, at present it is a technique which should be reserved for cases with long-standing ischaemia or failed previous surgery.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.