She denies any distal numbness, weakness, or tingling. On examination, she has mild swelling and tenderness over her ulna. Initial evaluation includes forearm radiographs shown in Figure How are Monteggia lesions classified? What are the most common associated injuries?
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She denies any distal numbness, weakness, or tingling. On examination, she has mild swelling and tenderness over her ulna. Initial evaluation includes forearm radiographs shown in Figure How are Monteggia lesions classified? What are the most common associated injuries? What are the indications and surgical principles for acute Monteggia injuries?
What are the anticipated outcomes of acute Monteggia care? What are the potential complications of missed Monteggia lesions? What are the indications and contraindications for reconstruction of chronic lesions? What are the principles and surgical techniques for chronic Monteggia reconstruction? What are the anticipated results and risks of recurrent instability following chronic Monteggia reconstruction? What are the potential complications of chronic reconstruction?
As with any traumatic injury in the child, prompt diagnosis and timely treatment continue to be the keystones for successful Monteggia care. A high index of suspicion combined with appropriate radiographic imaging and sound surgical treatment will result in successful outcomes in the vast majority of acute injuries.
Furthermore, despite the discouraging initial results, current strategies for reconstruction of the chronic lesion can lead to successful results in the majority of patients. In treatment of both acute and chronic situations, the principles of restoring ulnar length and alignment, while ensuring radiocapitellar stability, guide surgical care.
Etiology and Epidemiology Originally described by Giovanni Battista Monteggia in , Monteggia fracture dislocations refer to fractures of the ulna associated with proximal radioulnar joint PRUJ dissociation and radiocapitellar dislocations.
The mechanism of injury is classically described as a fall onto an outstretched hand with forced rotation of the forearm. Clinical Evaluation One chance is all you need. Isolated views of the ulna fracture are not sufficient; full-length anteroposterior AP and lateral radiographs of the forearm, including the elbow and wrist, are needed Figure Substandard or insufficient radiographic evaluation should not be accepted.
The tenet that the adjacent joints above and below should be assessed in any long bone fracture should be followed. Meticulous attention to radiocapitellar alignment in all views is mandatory. A: Lateral radiograph of the forearm demonstrates a short oblique mid-diaphyseal ulna fracture. B: AP forearm radiograph including the elbow and wrist demonstrates an associated anterior radial head dislocation.
Unfortunately, despite the increased awareness and understanding of Monteggia fracture dislocations, the initial diagnosis is often missed, resulting in late presentation, challenging surgical reconstruction, and suboptimal outcomes.
A number of published reports have documented a relatively high incidence of missed diagnoses. Normally, the longitudinal axis of the radius should bisect the capitellar ossification center on all radiographic views. While congenital radial head dislocations may occasionally present as acute injuries, the presence of a hypoplastic capitellum and convex radial head will usually confirm the diagnosis. In the majority of cases, the annular and quadrate ligaments are disrupted at the PRUJ; however, much of the interosseous membrane between the radius and ulna remains intact, as does the triangular fibrocartilage complex.
Anatomic reduction of the ulna, therefore, will often restore PRUJ and radiocapitellar joint congruity. For this reason, treatment is predicated on the nature of the ulna fracture. In addition, the biceps, anconeus, and long forearm flexors exert deforming forces on the proximal radius and ulna, contributing to radial head dislocation, ulnar shortening, and apex radial angulation.
Reversing or counteracting these forces is important during fracture manipulation and closed treatment. Historically, the Bado classification, based upon the direction of the radial head dislocation and apex of the associated ulnar fracture, has been utilized to describe these injuries Figure The mechanism of injury is thought to be due to a hyperextension injury combined with forearm pronation.
Reduction, therefore, involves longitudinal traction, supination, posteriorly directed pressure over the radial head, and flexion of the elbow to or degrees to minimize the deforming effect of the biceps. Deviation from a straight line drawn along the ulnar border should alert the examiner of a prior ulnar fracture and Monteggia lesion. Bado type II injuries refer to posterior radial head dislocations with apex dorsal ulnar fractures. Thought to be caused by an axial load on a partially flexed elbow or direct blow to the proximal supinated forearm, the reduction maneuver involves longitudinal traction with the elbow flexed combined with an anteriorly directed force over the radial head.
Bado type III injuries refer to lateral dislocations and varus fractures of the proximal ulna. Representing the second most common pattern in children, these too result from hyperextension and pronation with varus stress.
The need for open reduction is common. The fractures are typically mid-diaphyseal, with the radial fracture more distal than the ulnar fracture. Letts et al. This classification is helpful in surgical decision making. The clinical presentation of missed or chronic Monteggia fracture dislocations is quite varied. While distressing, the opportunity to effectuate meaningful restoration of anatomy and functional potential remains great, as no secondary joint changes have occurred.
Other patients will present months to years after injury, either with incidental radiographic diagnosis or for evaluation of new pain, noticeable loss of elbow flexion or forearm rotation, or with apparent deformity e. For many patients, there will be objective, but often minimally symptomatic, functional loss. Radiographs again confirm the diagnosis and guide treatment. Surgical Indications Set it and forget it. Closed reduction and cast immobilization alone has been advocated by many and is effective for plastic deformation and incomplete fractures, provided they are recognized acutely.
However, simple closed reduction alone has a number of disadvantages. First, there is a high risk of recurrent instability due to loss of reduction with cast immobilization alone Figure This is further compounded by the challenges in serial radiographic evaluation of the quality of reduction while the limb is casted, particularly for Bado type III injuries, which require AP views to assess for lateral displacement of the radial head.
Furthermore, effective immobilization of displaced Monteggia lesions often requires positioning the acutely injured, swollen limb in extreme positions. For the common Bado type I injuries, for example, hyperflexion is recommended, which may lead to issues with skin integrity and neurovascular compromise.
For these reasons, among others, we advocate surgical reduction and stabilization of all acute Monteggia fracture dislocations with complete ulnar fractures. A: Initial postreduction lateral radiograph of a Bado 1 Monteggia lesion. B: Loss of reduction is seen in cast. Notice the initial lateral was not perfectly reduced.
Chronic Monteggia lesions present a host of different challenges, due to the complexity of surgical steps needed to simultaneously reestablish a stable and mobile PRUJ and potential complications of operative treatment.
This is further clouded by the paucity of long-term information regarding the natural history of unreduced Monteggia fracture dislocations. Log In or Register to continue You may also need.
Monteggia vs. Galeazzi Fractures
Shakabar Monteggia fracture-dislocation in children. L8 — 10 years in practice. In children, the results of early treatment are always good, typically normal or nearly so. According to Reynders et al [ 3 ], open reduction of the radial head re reconstruction of the annular ligament could be responsible of a proximal synostosis between radius and ulna. One can hope that their contributions will be long remembered and celebrated.