- See:
brachial plexus
- Discussion:
- hx: persistant pain > 6 months: (poor prognosis);
- diff dx:
-
breast cancer (lower plexus and painful)
- radiation therapy (upper plexus and painless)
-
parsonage-turner syndrome : (may first affect
suprascapular)
- pancoast tumor:
- Exam: of Brachial Plexus:
-
vascular:
-
axillary artery avulsion (may be as high as 20%)
- consider
arteriogram;
-
neuro exam of the brachial plexus:
-
preganglionic vs postganglionic:
- preganglionic injuries have little potential for recovery;
-
supraclavicular deficits:
-
suprascapular (
supraspinatus);
-
dorsal scapular (
rhomboids);
-
long thoracic (
serratus): hence winging of scapula may indicate preganglionic injury;
-
infraclavicular deficits:
- medial and lateral pecotoral (
pectoralis major and minor);
- thoracodorsal (
latissimus): muscle is fired when patient coughs;
-
subscapular (
subscaplaris)
-
cords:
-
lateral cord: anterior divisions of the upper and middle trunk merge to form the lateral cord;
-
medial cord: anterior division from the lower trunk forms the medial cord
-
posterior cord:
- posterior divisions merge to become the posterior cord;
- shoulder abduction determines function of the axillary nerve;
- wrist extension determines low radial nerve function and elbow extension determines high radial nerve function;
- other:
- median and ulnar nerve function are determined by examining finger and wrist motion;
- elbow flexion evaluates musculocutaneous function;
- Studies:
- CXR: (elevated hemidiaphram)
-
C-Spine X-ray: (associated C spine fractures)
-
Arteriogram;
- CT myelogram: (rarely need to get myelograms)
- may be used to help dx a
preganglionic lesion;
- this study but should be delayed 6-12 wks, since a clot of blood may occlude the opening of pseudomenigocele;
- the finding of a large diverticula or meningocele is diagnostic for a preganglionic root
avulsion (as opposed to a post ganglionic extra-foraminal rupture);
-
EMG:
- some authors advocate EMG after 7-10 days, noting that a normal sensory evoked potential obtained from an anesthetic finger indicates
that the lesion is
preganglionic (otherwise there is a more distal nerve injury);
- the problem with early EMG, is that preganglionic injuries may occur along w/ dorsal root ganglion injuries which will falsely
indicate a postganglionic injury, and inaddition, early EMG cannot distinguish between to axonotmesis and neurotmesis;
- traditionally EMG has been performed at 3-4 weeks (look for F wave);
- w/
preganglionic lesion, see denervating potentials in segmental paraspinal muscles innervated by the posterior primary rami;
- references:
- Sensory nerve conduction after traction injuries of the brachial plexus.
G. Bonney and RW Gilliatt.
Proc. R. Soc. Med. Vol 51. 1958. p 365-367.
-
Clinical Diagnosis, Testing, and Electromyographic Study in Brachial Plexus Traction Injuries;
- The role of somatosensory evoked potentials and nerve conduction studies in the surgical management of brachial plexus injuries.
A. Landi et al.
JBJS. Vol 62-B. 1980. p 492-496.
-
Clinical examination versus routine and paraspinal electromyographic studies in predicting the site of lesion in brachial plexus injury.
- Initial Treatment:
- avoid a sling because of the propensity to acquire a fixed internally rotated and flexed shoulder, and will have stiff elbow;
- keep C-collar on and look for associatted C spine fractures
- in children and adults, if
biceps function has not return after 3 mo.
then consider operation;
- Surgical Treatment:
-
Shoulder in brachial plexus injuries:
-
Steindler Flexorplasty:
- w/ severe injury, one option is
AEA if the shoulder muscles are functioning;
Brachial plexus surgery. A. Narakas. Orthop Clin North Am 12 (1981), pp. 303–323.
