Bones under the skin are reliable reference points because they do not shift with fat or posture. Finding them by touch makes procedures safer and exams more precise.
Deltoid site
Find the lower edge of the acromion and inject into the thickest part of the deltoid, about two to three fingerbreadths below it. Staying high and central avoids the axillary and radial nerves.
Ventrogluteal site
Place the palm on the greater trochanter, the index finger on the anterior superior iliac spine and spread the middle finger along the iliac crest. Inject in the V between the fingers, well away from the sciatic nerve.
Chest landmarks
The sternal angle marks the second rib, the starting point for counting intercostal spaces. The lower half of the sternum is the hand position for CPR.
Intraosseous access and lumbar puncture
The flat inner surface of the proximal tibia, just below and inside the tibial tuberosity, is a common intraosseous site. A line joining the tops of the iliac crests crosses about the L4 spinous process.
| Landmark | How to find it | Used for |
|---|---|---|
| Acromion | Bony tip at the top of the shoulder | Deltoid injection |
| Greater trochanter | Bony bump on the side of the upper thigh | Ventrogluteal injection, pelvic binder |
| Sternal angle | Ridge where the manubrium meets the sternal body | Counting ribs, ECG leads |
| Tops of the iliac crests | Highest points of the hip bones | Lumbar puncture level |
| Tibial tuberosity | Bump below the kneecap | Intraosseous access |
At the bedside
Always find the landmark by touch before you mark or inject instead of estimating by eye. In patients with obesity, press firmly and confirm the site with more than one landmark.
Related guides
Written by Making Synapses. Topic reference: OpenStax, Anatomy and Physiology 2e (no text adapted).