Descriptive Terms

The surfaces of the bones present a great variety of eminences and depressions, as well as perforations. The prominences and cavities may be articular, or non-articular, furnishing attachment to muscles, tendons, ligaments or fascia. A number of descriptive terms are used to designate these features, and the following are some of those in general use:

Process (Processus) is a general term for a prominence.

A tuberosity (Tuber, Tuberositas) is a large, rounded projection; a tubercle (Tuberculum) is a smaller one.

The term trochanter is applied to a few prominences, e. g., the trochanters of the femur.

A spine (Spina) or spinous process (Processus spinosus) is a pointed projection.

A crest (Crista) is a sharp ridge.

A line (Linea) is a very small ridge.

A head (Caput) is a rounded articular enlargement at the end of a bone; it may be joined to the shaft by a constricted part, the neck (Collum).

A condyle (Condylus) is an articular eminence which is somewhat cylindrical; a non-articular projection in connection with a condyle may be termed an epicondyle.

A trochlea is a pulley-like articular mass.

A glenoid cavity (Cavitas glenoidalis) is a shallow articular depression, and a cotyloid cavity or acetabulum is a deeper one.

The term facet is commonly applied to articular surfaces of small extent, especially when they are not strongly concave or convex.

The terms fossa, fovea, groove or sulcus, and impression are applied to various forms of depressions.

A foramen is a perforation for the transmission of vessels, nerves, etc.

A sinus or antrum is an air-cavity.

Other terms, such as canal, fissure, notch, etc., require no explanation.