Monteggia fracture dislocation

1. MONTEGGIA FRACTURE
DISLOCATION

2. MONTEGGIA FRACTURE DISLOCATION
• This injury was described by Monteggia in the early
19th century.
• This is a fracture of the upper-third of the ulna with
dislocation of the head of the radius.

4. MECHANISM OF IINJURY
• It is caused by a fall on an out-stretched
hand.
• It may also result from a direct blow on the
back of the upper forearm.

5. TYPES
• These fall into two main categories depending upon
the angulation of the ulna fracture: extension and
flexion type.
• The extension type is the commoner of the two,
where the ulna fracture angulates anteriorly
(extends) and the radial head dislocates anteriorly.
• The flexion type is where the ulna fracture
angulates posteriorly (flexes) and the radial head
dislocates posteriorly.

6. DIAGNOSIS
Clinical features
• The ulnar deformity is usually obvious but the
dislocated head of radius is masked by swelling.
• Pain and tenderness on the lateral side of the
elbow.
• The wrist and hand should be examined for signs
of injury to the radial nerve.

7. X Ray
• It is essential to obtain a true anteroposterior
and true lateral view of the elbow.
• Usually, the head of the radius (which normally
points directly to the capitellum) is dislocated
forwards, and there is a fracture of the upper
third of the ulna with forward bowing.
• Backward or lateral bowing of the ulna is
likely to be associated with, respectively,
posterior or lateral displacement of the radial
head.
• Transolecranon fractures also are often
associated with radial head dislocation.

10. TREATMENT
• This is a very unstable injury, frequently redisplacing even if
it has been reduced once.
• If reduction is successful, a close watch is kept by weekly
chest X-rays for the initial 3-4 weeks

11. • In case, the reduction is not possible or if re-displacement
occurs, an open reduction and internal fixation using a plate
is performed.
• The radial head automatically falls into position, once the
ulna fracture is reduced.

12. COMPLICATIONS
• Nerve injury
• Malunion occurs commonly in cases treated
conservatively, because of an undetected
redisplacement within the plaster.
• It causes deformity of the forearm and limitation of
elbow and forearm movements.

13. REFERENCES
• ESSENTIAL ORTHOPAEDICS:
Maheshwari and Mhaskar (6th Edition)
• Apley Solomons System of Orthopaedics
and Trauma (10th Edition)