Locomotor brachii or locomotor brachialis

Locomotor brachii or locomotor brachialis

Locomotor brachii or locomotor brachialis is often described as a peripheral sign in severe aortic regurgitation or other causes of aortic runoff. It is the prominent pulsation of a usually tortuous brachial artery seen in severe aortic regurgitation. Sometimes it is called a dancing brachial artery as well.

Though taken as a peripheral sign of aortic regurgitation, it is not uncommon to see a prominently pulsating tortuous brachial artery in the elderly with arteriosclerosis. In this case it is a stiffened blood vessel wall which makes the pulsation visible and more prominent. Added to this there will be isolated systolic hypertension with a wide pulse pressure which is similar that in aortic regurgitation (AR). But the diastolic pressure will not be very low unlike in AR. If you palpate the vessel wall the vessel wall thickening can be easily appreciated (Osler’s sign). In order to appreciate the vessel wall thickening well, it may be better to obliterate the arterial pulsation by inflating a blood pressure cuff (sphygmomanometer cuff) above the systolic pressure.

Locomotor brachialis has been reported in a person with severe hypertension (225/170 mm Hg), who was aged only 50 years. He developed a dissecting aneurysm while on treatment [1].

Locomotor brachialis is also considered as a peripheral stigmata of arteriosclerosis and hypertension [2,3].

Reference

1. Beaven DW, Murphy EA. Dissecting aneurysm during methonium therapy; a report on nine cases treated for hypertension. Br Med J. 1956 Jan 14;1(4958):77-80. (Free Full Text at Pubmed Central).
2. Chaudhari TS, Verma R, Garg RK, Singh MK, Malhotra HS, Sharma PK. Clinico-radiological predictors of vascular cognitive impairment (VCI) in patients with stroke: a prospective observational study. J Neurol Sci. 2014 May 15;340(1-2):150-8.
3. Akintunde AA. The clinical value of the Tei index among Nigerians with hypertensive heart failure: correlation with other conventional indices. Cardiovasc J Afr. 2012 Feb;23(1):40-3.