The shoulder joint, or glenohumeral joint, is a highly mobile synovial ball-and-socket joint that allows for a wide range of movements including flexion, extension, abduction, adduction, internal rotation, and external rotation. Its mobility is facilitated by the shallow socket of the scapula and the flexibility of surrounding muscles and ligaments, but this also makes it susceptible to instability and injury.

Shoulder Joint Movements

The shoulder joint, also known as the glenohumeral joint, is a ball-and-socket joint that allows for a wide range of motion but is inherently less stable compared to other joints. Its stability is primarily maintained by a combination of muscles, tendons, and ligaments, making it susceptible to injuries such as dislocations and rotator cuff tears.

Shoulder Joint

The glenohumeral joint, commonly known as the shoulder joint, is a ball-and-socket joint that allows for a wide range of motion, making it one of the most mobile joints in the human body. Its stability is primarily maintained by a combination of muscles, tendons, and ligaments, rather than the bony structures alone, making it susceptible to dislocations and injuries.

Glenohumeral Joint

Mobile synovial ball-and-socket joint

Range of movements

Flexion is the movement that decreases the angle between two body parts, typically occurring at a joint. It is a fundamental motion in biomechanics, essential for activities such as walking, lifting, and bending.

Flexion

Extension refers to the process of expanding, enlarging, or prolonging something beyond its original limits, often used in various academic and practical contexts such as linguistics, mathematics, and computer science. It involves the application of existing knowledge or systems to new areas, thereby increasing their scope and utility.

Extension

Abduction is a form of logical reasoning that involves inferring the best possible explanation for a set of observations or facts. It is often used in scientific inquiry and everyday problem-solving to generate hypotheses when information is incomplete or uncertain.

Abduction

Adduction is a movement that brings a limb or body part closer to the midline of the body or towards another body part. It is a fundamental motion in various physical activities and is crucial for maintaining balance and coordination in the human body.

Adduction

Internal rotation refers to the movement of a joint towards the center of the body, often involving the shoulder or hip joints. This movement is crucial for various physical activities and is a key focus in physical therapy and sports training to ensure joint stability and prevent injuries.

Internal Rotation

External rotation is the movement of a joint away from the center of the body, typically involving the rotation of a limb around its long axis. This motion is crucial in various physical activities and is essential for maintaining joint stability and range of motion.

External Rotation

Mobility of the shoulder

Shallow socket of the scapula

Flexibility of surrounding muscles

Ligaments are strong, fibrous connective tissues that connect bones to other bones, providing stability and support to joints. They play a crucial role in maintaining the structural integrity of the skeletal system by limiting excessive movement and preventing dislocations.

Concepts

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