Concave
Concave (Concavity): A shape is concave if at least part of it curves inward. That is, the outline or surface is curved like the interior surface of a bowl. A simple mnemonic: the "cave" in "concave" hints at being an inward curvature or hollowing like a cave's entrance.
- Opposite (Antonym): Convex (outward curvature)
- Practice Specific Example: Convex/Concave Rule
For more examples of the use of these terms in anatomy (including video lectures), check out:
Examples of Concave and Convex Surfaces in the Human Body
Bone Landmark Terminology
- Fossa: A concave depression in a bone.
- Tubercle: A convex, rounded projection on a bone.
- Groove: A concave, linear depression in a bone.
- Condyle: A convex or spherical end of a bone.
Joints:
- Shoulder (Glenohumeral) joint: The glenoid fossa ("shoulder socket") is a concave surface, and the humeral head is a convex surface.
- Hip (Pelvifemoral) Joint: The acetabulum ("hip socket") is a concave surface, and the femoral head is a convex surface.
- Knee (Tibiofemoral) Joint: The tibial plateau is slightly concave (made "deeper" by the menisci), and femoral condyles are convex.
- Spine: Generally, the superior articular surface is slightly concave to receive the slightly convex inferior facet.