Glenohumeral joint

A highly mobile joint that connects the humerus to the scapula, allowing for a wide range of arm movements.

The glenohumeral joint, commonly known as the shoulder joint, is a synovial ball-and-socket joint formed by the articulation between the head of the humerus and the glenoid cavity of the scapula. This joint is crucial for upper limb mobility and plays an essential role in various daily activities involving arm movements.

Terminologia Anatomica

articulatio humeri

System

Skeletal system

Function

The glenohumeral joint is primarily responsible for facilitating a remarkable range of motion in the shoulder, enabling movements such as flexion, extension, abduction, adduction, and rotation of the arm. It allows the arm to move in multiple directions, which is vital for actions such as throwing, lifting, and reaching. Its unique structure, featuring a shallow glenoid cavity and a large humeral head, permits comprehensive flexibility but also makes it prone to dislocation and injuries. Additionally, the joint's dynamic stabilization is achieved through a complex interplay of muscles, tendons, and ligaments, particularly the rotator cuff, which reinforces the joint and maintains its stability during movement. Overall, the glenohumeral joint is essential not only for mobility but also for the strength required in many activities, making it integral to daily function.

Location

Located at the shoulder region, the glenohumeral joint sits between the upper arm bone (humerus) and the shoulder blade (scapula). The humeral head fits into the shallow glenoid cavity of the scapula, allowing for the arm's excellent range of motion. It is situated laterally to the thoracic cavity and superiorly to the ribs, positioned in such a way that it allows for extensive upper limb mobility. The joint is surrounded by a joint capsule that contains synovial fluid, facilitating smooth movement and cushioning the joint during various activities. The surrounding muscles and tendons, including those of the rotator cuff, play critical roles in both stabilizing the joint and allowing for its varied movements.

Did You Know?

The glenohumeral joint has one of the largest ranges of motion of any joint in the human body.
Despite its mobility, the shoulder joint is one of the most commonly dislocated joints due to its anatomical structure.
The rotator cuff is a group of four muscles that surround the glenohumeral joint, providing stability and enabling its complex movements.
Athletes engaged in sports requiring overhead motions are particularly susceptible to shoulder injuries related to this joint.