the shoulder and ends about one-third of the waydown your up per arm.
It's wide at the shoulder and tapers to a V shape farther down.
You may be able to feel the V with your fingers if you lift your arm to the side until it is parallel to the floor.
This will tighten the muscle and make it feel harder.
We usually use the deltoid muscle because it is easy to find, is relatively large and thick, and is less likely to be covered with a deep fat pad than most other muscles. 2.
Now, allow your nondominant arm (left if you're right-handed) to dangle loosely at your side.
This will relax the muscle, so that the needle can penetrate easily. 3.
The site for injection will be near the upper (wider) end of the deltoid, about \l/z inches below your shoulder (at about the po sition of the arrow in Figure 19-2).
We use the wide end of the muscle because you are less likelyto miss it with the needle, and because you would not want to pierce the axillary nerve, which is located near the tip of the V, at the lower end.