Saturday, March 28, 2015

Elbow fractures in the elderly. The Monteggia variant fracture with associated fracture dislocation of the radial head.

This is a 74 y/o F with a fracture dislocation of the radial head and an associated fracture of the proximal ulna. This mechanism represents a variant of the Monteggia fracture pattern. It is preferable to have a low threshold for replacement of the radial head. Fixation of the radial head can be challenging in this age group due to (1) Poor Bone quality (2) Comminution

It should be highlighted that in this injury pattern it is of great importance to reduce the ulnar fracture to the best anatomic position. In situations like in this case the comminution at fracture side can be an obstacle to anatomic reduction. The reasoning behind this recommendation is that the interosseous membrane and ligamentous interconnections of the proximal ulna to the radial head will directly affect the position of the radial head relative to the distal humerus. In other words, if the ulnar fracture is malreduced then the radial head with stay in a malreduced position in the form of subluxation or dislocation that is irreducable in the operating room. Even worse scenarios are when it is reduced in the operating room but it represents an unstable condition and dislocation is  seen later on at the initial postoperative xrays in the office.

In addition, it is important to avoid overstuffing of the radiocapitellar joint by choosing a smaller radial head implant (one size down to the native head) and avoid prominence of the head in relation of the articular surface of the ulna. Overstuffing leads to stiffness, pain and early arthritis.

At 3 months postop the fracture has healed and the patient had ROM of 10-140 flexion with 70 to full supination/pronation

Xrays of this case as shown above.