Understanding Shoulder External Rotation at 90 Degrees Abduction

Shoulder external rotation at 90 degrees abduction is a crucial movement in both rehabilitation and general shoulder function. This article delves into the anatomical, functional, and clinical aspects of this movement, providing comprehensive insights for practitioners in the fields of Health & Medical, Education, and Chiropractors.

Anatomy of the Shoulder Joint

The shoulder joint, or glenohumeral joint, is a complex structure composed of bones, muscles, ligaments, and tendons that work together to facilitate a wide range of motion. Understanding its anatomical layout is fundamental to appreciating the significance of shoulder external rotation at 90 degrees abduction.

• Bones: The shoulder comprises several key bones including the humerus, scapula, and clavicle.
• Muscles: Major muscles involved in shoulder motion include the rotator cuff group (supraspinatus, infraspinatus, teres minor, and subscapularis) and the deltoid muscle.
• Ligaments: Ligamentous structures provide stability to the joint, preventing dislocations and supporting mobility.

The Motion of Shoulder External Rotation

Shoulder external rotation