BRUCE DOOLIN
The shoulder (glenohumeral) joint is the articulation between the glenoid fossa of the scapula and the humerus. As A multiaxial joint, it allows movement in three planes. The motions possible are: flexion and extension in the saggital plane, abduction and aduction on the frontal plane, external and internal rotation and horizontal flexion and extension in the transverse plane, and circumduction in a combination of planes. The scapula and glenohumeral joints work together and use highly synchronized and coordinated movements to perform most functions of the upper extremities.