Monteggia fracture is not a simple fracture. It is a
fracture of the proximal ulna with dislocation of the radial head. Monteggia
fracture can happen in children and in adults. It is one of the most common
injuries that is missed in the emergency room in children. The radial head may
be dislocated or subluxed, and this problem may not be clear on x-rays. If this
injury is missed, then the child will probably need a big surgery to deal with
this big problem. Treatment of this fracture depends on the age of the patient.
In general, in pediatric patients, you will do closed reduction of the ulna and
closed reduction of the radial head. In adult patients, you will do open
reduction with internal fixation of the ulna with dorsal plate and closed
reduction of the radial head. A line drawn from the proximal radius should
bisect the capitellum in all x-ray views. If you are in doubt and not sure, get
x-rays of the other side and compare. Always examine the patient for posterior
interosseous nerve injury.
The most common type is anterior Monteggia. That
means that the apex of the fracture is anteriorly and the radial head goes
anteriorly. Just make it a practice, when you have a fracture of the proximal
ulna, look at the radius and the radial head, and see the position of the
radial head in relationship to the capitellum. Anterior Monteggia is more
common in children. Posterior Monteggia constitutes 70-80% of Monteggia
fractures in adults. There are four types of Monteggia: Type I, Type II, Type
III, and Type IV. Monteggia fracture is classified according to the direction
of displacement of the radial head. The radial head has two relations: relation
with the capitellum and relation with the proximal radioulnar joint. When the
radial head subluxes or dislocates, it subluxes or dislocates from these two
joints. The radial head becomes free. This means that the radius is not
connected to the capitellum or to the superior radioulnar joint. A Type I
fracture is of the middle or the proximal third of the ulna with anterior
dislocation of the radial head, and it has the characteristic that the apex of
the ulnar fracture is anteriorly. Type I fracture is the most common of all
types (especially in children). Type I occurs in about 60% of fractures. In
children, reduce the fractured ulna and reduce the dislocation of the radial
head and immobilize the elbow in flexion and supination. When you flex the
elbow, especially more than 90 degrees, you will relax the biceps (watch the
circulation). A Type II fracture is a posterior type fracture. Posterior
Monteggia is the most common type in adults. It is associated with a higher
complication rate and carries the worst prognosis. 15% of Monteggia fractures
are Type II. It is a fracture of the middle or proximal third of the ulna with
posterior dislocation of the radial head. You should immobilize the elbow in
extension. Type III is a lateral Monteggia. About 20% of Monteggia fractures
are Type III. It is a fracture of the proximal ulna with lateral dislocation of
the radial head. 5% of Monteggia fractures are Type IV; it is very rare. It is
a fracture of the proximal ulna with anterior dislocation of the radial head
and fracture of the proximal third of the radius below the bicipital
tuberosity. The patient will need surgery, even in children. In this case, the
radial head is dislocated, and you also have fractures of the radius and the
ulna. The posterior interosseous nerve is adjacent to the radial neck, placing it
at risk for a traction injury with dislocation of the proximal radius.
You
should do a neurovascular examination. A nerve injury which involves the
posterior interosseous nerve is not uncommon. Ask the patient to “hitchhike”
and extend their fingers. Make sure the wrist is in dorsiflexion when you ask
the patient to extend the fingers. In posterior interosseous nerve injury, the
finger extensors will not be working. If the posterior interosseous nerve is
injured, observe the patient. In case of posterior interosseous nerve injury in
Monteggia fracture, you will reduce and stabilize the fracture and reduce the
radial head dislocation. Observe the nerve; do not explore the nerve. Typically
the nerve injury is a neuropraxia. It can be expected to resolve itself with
observation in 6-12 weeks. If it does not resolve, you will do EMG and nerve
studies after that period of observation. Any time that you have an ulnar shaft
fracture or any fracture of the proximal ulna, check the radial head position.
Make sure that the radial head is reduced to the capitellum (be aware that the
subluxation may be subtle). Recognition of Monteggia fracture in children is
important. Early appropriate treatment is much easier than treating a missed
radial head dislocation. To treat a Monteggia fracture in adult patients, do
open reduction internal fixation (ORIF) of the ulna. When the ulna is properly
aligned and fixed, the radial head will reduce by itself. After fixation of the
ulnar fracture, if the radial head is still not reduced, then assess the ulnar
reduction. Check for malalignment or malreduction of the ulna. It is imperative
that you restore the length and the proper alignment of the ulna, so that the
radial head can be reduced. If we malalign the ulna, then the radial head will
remain subluxed. Radial head instability may be caused by nonanatomic reduction
of the ulna or by interposition of the annular ligament. Fracture of the ulna
may be too comminuted, and it may not be reduced properly. The fracture may
also need bone graft later on for healing. A Monteggia variant associated with
radial head fracture, in addition to dislocation of the radial head fracture,
in addition to dislocation of the radial head and fracture of the ulna can be a
problem. The radial head fracture is usually fixed or replaced, a prosthesis is
used to replace the radial head in the elderly, especially if the fracture is
comminuted. The subluxation of the radial head is reduced, and the fractured
ulna is fixed as usual. Treatment is different in pediatric patients. The
radial head ossifies around four years of age. In Type I, Type II, and in Type
III Monteggia fractures, you will do closed reduction of the ulna to restore
the length of the ulna, and you will do closed reduction of the radial head.
Closed reduction is much more successful in young children. In anterior
Monteggia, you will immobilize the elbow in flexion and supination. In
posterior Monteggia, you will immobilize the elbow in extension. Ulnar fixation
with a rod or a plate is needed in older patients with unstable fractures. Type
IV fractures require surgery. Surgery is also done in cases where we are unable
to restore the proper length of the ulna, we are unable to reduce the ulna, and
we are unable to reduce the radial head. In this situation, we can use IM rod
or a plate. Dislocation of the radial head with fracture of both the radius and
ulnar shaft. Do closed reduction of the radial head with intramedullary pin
fixation of the radius and the ulnar shaft fractures. The radius and ulnar
shaft fractures are stabilized surgically to give a lever arm for reduction of
the radial head. In this type of fracture, the radial head subluxation may be
missed or unappreciated, because the focus is usually on the forearm fractures.
To treat a missed or neglected Monteggia fracture in children, do osteotomy of the
ulna and lengthening with correction of the angulation, and reduction of the
radial head in addition to plating of the ulna. The patient may need open
reduction of the radial head.
With elbow dislocations, recognize the terrible triad: elbow
dislocation, radial head fracture, and coronoid fracture. The terrible triad is
not a simple elbow dislocation; it is a complex elbow dislocation. In addition
to these three injuries of the elbow, there is always a tear of the lateral
ulnar collateral ligament. The treatment usually is reduction and splinting of
the elbow.
This cannot be the definitive treatment; it is the initial
treatment. If no surgery is done, you will have recurrent dislocation of the
elbow. You need to do surgery for reduction and fixation of the fractures and
also to restore the elbow stability. This injury is unstable. Simple reduction
and splinting is not going to work for this injury. You have to recognize the terrible
triad which means surgery. There are multiple types of elbow dislocation based
on the position of the olecranon relative to the humerus. The most common type
of elbow dislocation is the posterolateral type. There are two basic types of
elbow dislocations: simple and complex. Simple elbow dislocations have no
fracture seen, and are usually a ligamentous injury. Complex elbow dislocations
have associated fractures in addition to the ligamentous injury. With any elbow
dislocation, you need to check the shoulder and the wrist for injuries and
fractures because it can occur in up to 15%. When you have a simple dislocation
of the elbow, you need to reduce it and then check the range of stability of
the elbow. If you find that the elbow is stable with range of motion, then you
will do a short period of immobilization with a posterior splint for
approximately one week with the elbow in about 90 degrees of flexion. Then start
active range of motion of the elbow. Recurrence of the dislocation is rare
(less than 1%). If you keep the elbow immobilized more than 3 weeks, there will
be severe stiffness of the elbow. Surgery should be done if the dislocation is
irreducible, if there is associated fracture, or if you are unable to maintain
stability of the elbow. After immobilization and early range of motion of the
elbow, you will see the patient and do follow up x-rays to check joint
congruity and to make sure that the elbow reduction is maintained. To treat the
terrible triad, you should initially do a closed reduction. Open reduction and
internal fixation of the coronoid (if possible), of the radial head or excise
the radial head with radial head arthroplasty if the radial head is
unreconstructable. In addition, you will do lateral ulnar collateral ligament (LUCL)
repair. Never excise the radial head alone in this situation. For an elbow
dislocation with olecranon fracture, do open reduction and plate fixation.
K-wires and tension band is not strong enough to hold the fracture and
stabilize the elbow at the same time. For an elbow dislocation with a radial
head fracture, do fixation or replacement of the radial head (never do excision
of the radial head alone in this situation). The LUCL is the most important
lesion in recurrence or persistence of instability of the elbow following
simple elbow dislocation.
The injury progresses from lateral to medial. The lateral
collateral ligament fails first, and it avulses proximally at the lateral
epicondyle. The medial collateral ligament (MCL) fails last. In varus
posteromedial rotary instability, there is an elbow injury plus LUCL tear, plus
coronoid fracture which involves the medial facet of the coronoid. Treatment for
chronic dislocation is open reduction capsular releases with hinge external
fixation and early range of motion. Loss of terminal extension is a
complication of elbow dislocation. Usually for decreased range of motion of the
elbow, you will do static progressive splinting between 6-10 weeks. No manipulation
of the elbow is done, which is different from the knee after total knee
replacement, where you can do manipulation up to three months. With heterotopic
ossification, do excision. Remove the myositis and excise the posterior part of
the MCL to allow more flexion. To be functional, the range of motion of the
elbow should be between 30-130 degrees. Some physicians suggest that if the
flexion is less than 100, you will do release of the posterior bundle of the
MCL in addition to release of the ulnar nerve. If you want more flexion of the elbow,
excise the posterior part of the MCL.
Fractures of the olecranon may occur due to a direct blow to
the elbow or from a fall onto an outstretched hand. Nondisplaced fractures have
less than 2mm of separation and are considered stable. Fracture separation will
not increase with elbow flexion. Extensor mechanism is intact and the patient
will be able to extend the elbow against gravity. Displaced fractures could be
an avulsion, oblique, transverse, comminuted, or dislocated.
Olecranon fracture dislocations can be anterior (transolecranon)
or posterior (similar to monteggia fracture dislocation). An examination will
show that the patient is unable to extend the elbow with these displaced
fracture types. A true lateral view x-ray will clearly show the olecranon
fracture. Usually, these fractures are followed by stiffness of the elbow in
about 50% of the patients. However, this does not affect the function.
The goal of treatment for olecranon fractures should be
restoration of the articular surface, preservation of the continuity of
extensor mechanisms, maintain elbow stability, and avoid stiffness of the
elbow. Nonoperative treatment is used for nondisplaced fractures and it may be
used for some displaced fractures in elderly patients (treat elbow in some
flexion with a splint). I would personally use minimally invasive techniques in
these patients unless the skin is very bad, or the fracture is very comminuted.
There are three techniques used for surgical treatment: the
tension band technique, detach olecranon and reattach triceps, and plate and
screw fixation. The tension band technique is only used for transverse fractures
with no comminution. K-wires and screws are used, and the surgeon may use
either a 6.5mm screw or Kwires for the tension band. When doing the tension
band technique, you want to engage the anterior cortex of the ulna. The surgeon
should avoid over penetration to avoid affecting the forearm rotation or
injuring the anterior interosseous nerve. The surgeon needs to be sure that the
pins are not fixing the radius and that after the operation, the patient can
perform pronation and supination of the forearm (pull the pins out slightly if
needed). The distractive force of the triceps is converted to compression force
at the articular surgace, especially when bending the elbow. The drill hole for
the K-wire should be positioned about 4-5cm from the fracture which gives
enough safe distance so that the fracture will not propagate. Place the tension
band wire through the drilled holes before application of the K wires. The
surgeon should be sure that the hook to the K-wire is posterior. Make sure that
the tension band wire is close to the bone so there is no laxity in the
fixation and instability. An intramedullary screw could be used. This screw
fixation may need a washer to capture the tension band wire. Intramedullary
6.5mm screw fixation is a reasonable option for fixation but it may need to be supplemented
with tension band wires. Never use cancellous screw alone. The tension band
technique are for transverse fractures of the olecranon. If fractures
comminution is present, change the plan of fixation.
When detaching the olecranon and reattaching the triceps, an
excision of the fracture fragment and triceps advancement is used:
If the fracture is less than 50%
To treat elderly patients (especially if
fracture is comminuted)
For some nonunions when the fracture is small
and cannot be fixed
The surgeon must be sure that the procedure is done with the
elbow is stable. If the elbow has ligamentous instability and excision of the
fracture fragment is done, this will make the elbow very unstable. The triceps
should be attached closer to the articular surface.
Special olecranon plates are available when using a plate
and screw fixation technique. The bridge plate and screw fixation technique is
used in comminuted, Monteggia, oblique fractures extending to the coranoid, and
fracture dislocation. The plate is placed on the tension side of the olecranon
(dorsal side). Sometimes, an opening is made through the triceps and the plate
is placed against the bone, then suturing the triceps tendon over the plate to
avoid hardware prominence.
In summary, if the patient is elderly with a small,
comminuted fracture fragment less than 50% of the joint space, excise the
fragment, and reattach the triceps tendon to the olecranon. If the olecranon
fracture is transverse and proximal to the base of the coranoid process, then
use the tension band technique. Use plate fixation for all olecranon fracture
scenerios, such comminuted fractures, oblique fractures, unstable fractures, dislocation,
or fractures distal to the coranoid process. The typical exam question scenario
will discuss a comminuted fracture that should be treated with a plate. You
probably need to remove above 20% of the plate fixations due to hardware irritation.
Hardware irritation is worse with the tension band surgical treatment (may need
to remove in more than 50% of cases).
An Elbow dislocation occurs when the radius and ulna bones
of the forearm move out of place from the humerus bone of the upper arm. There
are two basic types of elbow dislocations:
Simple
No fracture of the bones around the elbow
joint
Usually ligamentous injury
Complex
Fracture has occurred along with ligamentous
injury
Simple elbow dislocations typically occur when the patient
falls onto an outstretched hand. Injury progression from lateral to medial in
most patients. Posterolateral simple dislocations are the most common, occurring
approximately 90% of the time.
The proximal ulna and radius are displaced
posterolaterally relative to the distal humerus. Postemedial dislocations occur
at the proximal ulna and radius and are displaced posteromedially relative to
the distal humerus. In medial dislocations, the proximal ulna and radius are
displaced medially relative to the distal humerus. With lateral dislocations,
the proximal ulna and radius are displaced laterally relative to the distal
humerus. Anterior dislocations are rare, as they result from a direct force
applied to the posterior aspect of the forearm with the elbow in a flexed
position. Anterior dislocations occur when the proximal ulna and radius are
displaced anteriorly relative to the distal humerus. If stable, simple acute
fractures can be treated with a closed reduction and a splint for two to three
days (no more than two weeks) in addition to range-of-motion exercises and
physical therapy. Unstable simple fractures are rare, but can be stabilized by
ligament repair and/or by the use of an external fixator or cross pinning of
the joint in the elderly.
Chronic Elbow dislocations will need to be treated with an
open reduction and external fixator and is usually hinged. Recurrent elbow
dislocations (diagnosed by pivot shift) occurs due to a deficiency of the
lateral collateral ligament and is treated by a reconstruction of the
ulnohumeral ligament with a tendon graft.
