Monteggia fracture
The key to treatment is prompt recognition of the injury pattern as well as stable anatomical reduction of the ulna.
Attention must be paid to appropriate treatment of associated injuries at the level of the elbow, including fractures of the coronoid process and the radial head as well as posterolateral rotatory instability of the ulnohumeral articulation. It is important that you have a close look at the elbow joint (radial head and coronoid process). The Bado II fracture often represents a combined injury of the elbow and the forearm
Classification
Monteggia (1814) fractures are classically described as a dislocation of the radial head and fracture of the ulna. Bado subclassified this into four types.
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Bado Classification (1967)I -Anterior dislocation of the radial head and fracture of the diaphysis of the ulna at any level, with anterior angulation of the fracture fragments. II - Posterior or posterolateral dislocation of the radial head and fracture of the diaphysis of the ulna, with posterior angulation of the fracture fragments. III - Lateral or anterolateral dislocation of the radial head and fracture of the metaphysis of the ulna. IV - Anterior dislocation of the radial head and fracture of the proximal third of the radius and ulna at the same level. |
Treatment
Urgent treatment, Open fractures emergency.
The challenge is to obtain stable fixation of the ulna without violating the trochlear notch with screws. Fix the ulna with a strong (DCP) plate on the posterior surface (tension surface). A plate applied to the lateral or medial surface of the ulna is less mechanically effective. Contour the plate to reach the tip of the olecranon. Semitubular, one-third tubular plates and tension band-wire constructs are not strong enough.
Special situations
Radial Nerve injury
If radial or posterior interosseous nerve palsy occurred at the time of injury and the radial head easily reduces, suggest do not explore the radial or posterior interosseous nerve at the time of surgery. This is usually a neuropraxia, and function will return within 6 to 12 weeks after injury in the majority of cases. If the nerve is not functioning at 3 months, diagnostic studies are indicated, and, depending on the results, exploration of the nerve may be considered.
Open Fractures
Open fractures should be treated as emergencies, with debridement and
stabilization (plating). Suggest delayed closure of wounds. External fixation is
used only in severely contaminated wounds.
Extensive comminution of the ulnar shaft extending proximally into the olecranon
can present problems with regaining anatomic length of the ulna. If the radial
head is reduced and is stable, this facilitates reconstruction of the length of
ulna so that it can be plated to its normal anatomic length. If the radial head
is unstable, it is important to open the elbow joint, ensure the reduction of
the radial head under direct vision, and then restore the length to the ulna.
Irreducible Radial Head
If closed reduction is not successful in reducing the radial head, open reduction is indicated. Through a separate approach to the radial head or by extending the approach to the ulna proximally so that the elbow joint can be visualized. The usual impediments to reduction are the anterior capsule and, at times, the annular ligament. With an arthrotomy of the elbow joint, the radial head can be easily reduced and the capsular structures repaired. Repair the annular ligament if posible.
Radial Head Fracture
Treat as for radial head fractures; open reduction and internal fixation of the
radial head if possible should be done. Excision of the radial head if the
fracture cannot be reconstructed and if elbow stability is jeopardized consider
prosthetic radial head replacement.
If a fracture of the radial head is fixed operatively, it is imperative that no
prominent implant be placed on the articular surface of the radial head.
JBJS - A 1998 80: 1733-44 - Monteggia Fractures in Adults - Ring D, Jupiter JB, Simpson NS
Clin Orthop 1967 Jan-Feb;50:71-86 - The Monteggia lesion.- Bado JL.