Background: Recent interest in reconstruction
of the upper limb following brachial plexus injuries has focused
on the restoration of prehension following complete avulsion of
the brachial plexus.
Methods: Double free muscle transfer was performed
in patients who had complete avulsion of the brachial plexus. After
initial exploration of the brachial plexus and (if possible) repair
of the fifth cervical nerve root, the first free muscle, used to
restore elbow flexion and finger extension, is transferred and reinnervated
by the spinal accessory nerve. The second free muscle, transferred
to restore finger flexion, is reinnervated by the fifth and sixth intercostal
nerves. The motor branch of the triceps brachii is reinnervated
by the third and fourth intercostal nerves to restore elbow extension.
Hand sensibility is restored by suturing of the sensory rami of
the intercostal nerves to the median nerve or the ulnar nerve component
of the medial cord. Secondary reconstructive procedures, such as
arthrodesis of the carpometacarpal joint of the thumb, shoulder
arthrodesis, and tenolysis of the transferred muscle and the distal
tendons, may be required to improve the functional outcome.
Results: The early results were evaluated in
thirty-two patients who had had reconstruction with use of the double
free muscle procedure. Twenty-six of these patients were followed
for at least twenty-four months (mean duration, thirty-nine months)
after the second free muscle transfer, and they were assessed with
regard to the long-term outcome as well. Satisfactory (excellent
or good) elbow flexion was restored in twenty-five (96 percent)
of the twenty-six patients and satisfactory prehension (more than
30 degrees of total active motion of the fingers), in seventeen
(65 percent). Fourteen patients (54 percent) could position the
hand in space, negating simultaneous flexion of the elbow, while
moving the fingers at least 30 degrees and could use the reconstructed
hand for activities requiring the use of two hands, such as holding
a bottle while opening a cap and lifting a heavy object. The results
were analyzed to identify factors affecting the outcome.
Conclusions: The double free muscle procedure
can provide reliable and useful prehensile function for patients with
complete avulsion of the brachial plexus.