Peculiarities
The ulnar artery varies in its origin in the proportion of about one in thirteen cases; it may arise about 5 to 7 cm. below the elbow, but more frequently higher, the brachial being more often the source of origin than the axillary.
Variations in the position of this vessel are more common than in the radial. When its origin is normal, the course of the vessel is rarely changed.
When it arises high up, it is almost invariably superficial to the Flexor muscles in the forearm, lying commonly beneath the fascia, more rarely between the fascia and integument.
In a few cases, its position was subcutaneous in the upper part of the forearm, and subaponeurotic in the lower part.
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