Background: Dislocation of the elbow joint
is the second most common dislocation in the upper extremity, dislocation
of the shoulder being the most common. It has been reported that
uncomplicated dislocation of the elbow joint may be associated with
a decreased range of motion, degenerative changes in the elbow joint,
ectopic calcification, or neurological deficits. As the medial collateral
ligament complex can be completely disrupted during dislocation,
we evaluated the association between the long-term results of treatment
of simple posterolateral dislocation of the elbow and the presence
of persistent medial or valgus elbow instability.
Methods: Fifty patients who had a mean age of
thirty-three years (range, eighteen to fifty-eight years) had closed
reduction of a posterolateral dislocation of the elbow without associated
fractures. The extremity was immobilized in an above-the-elbow plaster
cast for three weeks. After a mean duration of follow-up of nine
years (range, six to thirteen years), forty-one patients were evaluated
with an interview, a physical examination, and radiographs made
while a valgus load was applied to the elbow.
Results: The average score according to the
system of The Hospital for Special Surgery was 91 points (range, 49
to 100 points), and thirty-one patients described their elbow function
as good or excellent. Twenty-four patients had evidence of medial
instability on radiographs made while a valgus load was applied to
the elbow. Twenty-one patients had signs of degeneration of the
joint, and twenty-five patients had ectopic ossification. Magnetic
resonance imaging combined with arthrography was performed for the
first twenty patients; eight had evidence of rupture of the medial
collateral ligament, seven had generalized degenerative changes
of the cartilage, and four had a chondral defect of the capitellum.
(The study could not be completed for the remaining patient.) Medial
instability on radiographs was correlated with signs of degeneration (p
= 0.001), ectopic ossification (p = 0.01), a worse score according
to the system of The Hospital for Special Surgery (p = 0.002), and
persistent pain (p = 0.04).
Conclusions: Posterolateral dislocation of the
elbow joint can lead to persistent valgus instability that is associated
with a worse overall clinical and radiographic result.