Scapula

The connector of the upper arm with the collar bone is termed as Scapula. This acts the posterior or the back side of the shoulder girdle and is triangular in shape. The front part of this bone is a broad concavity with a number of oblique ridges in the two third of the medial part. These ridges are connected by thin fleshy fibers and its arched form provides maximum support to the spine. The lateral third is covered with fibers of the muscle and very smooth to touch. The dorsal or the back part is unevenly divided and connected to the spine. The upper division is lesser than the lower division and both are supportively connected for providing the right usage for the upper arm.