Glenoid fossa

Glenoid cavity of left scapula - animation

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Glenoid cavity of scapula - animation01

Gray328

Scapula ant numbered

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Shoulder muscle - force couple of rotator cuff

Glenoid fossa is a shallow depression located on the lateral aspect of the scapula, serving as the socket for the ball and socket joint of the shoulder. It articulates with the humerus to form the glenohumeral joint, which is responsible for the wide range of motion of the arm. The shape of the glenoid fossa is somewhat pear-shaped, being wider at the bottom than at the top, which aids in the stability and mobility of the shoulder joint.

Anatomy

The glenoid fossa is surrounded by a rim of fibrocartilage called the glenoid labrum, which deepens the cavity and provides additional stability to the joint. The surface of the fossa is covered with articular cartilage, which reduces friction and absorbs shock during movement. The scapula itself is a flat, triangular bone that sits on the posterior side of the ribcage, and the glenoid fossa is located on its lateral angle.

Ligaments, including the glenohumeral ligaments and the coracohumeral ligament, attach around the glenoid fossa and contribute to the joint's stability. The rotator cuff, a group of muscles and their tendons, also plays a crucial role in stabilizing the shoulder joint by holding the head of the humerus firmly within the glenoid fossa.

Function

The primary function of the glenoid fossa is to facilitate shoulder joint movements, including flexion, extension, abduction, adduction, and rotation. This wide range of motion makes the shoulder one of the most mobile joints in the body, allowing for a vast array of arm movements. However, this mobility also makes the shoulder more susceptible to dislocation and instability issues, particularly if the supporting structures around the glenoid fossa are damaged or weakened.

Clinical Significance

Conditions affecting the glenoid fossa can lead to pain, reduced mobility, and instability in the shoulder. Common issues include glenoid labrum tears, shoulder dislocations, and arthritis of the shoulder. Treatment for these conditions may involve physical therapy, medication, or surgery, depending on the severity and underlying cause.

Surgical Interventions

In cases where conservative treatments are ineffective, surgical interventions such as arthroscopy or shoulder replacement surgery may be necessary. During shoulder replacement, the damaged glenoid fossa can be resurfaced or replaced with a prosthetic component to restore joint function.