Which joint is the single attachment between the axial and appendicular skeletons?

Which joint is the single attachment between the axial and appendicular skeletons?

• A. Sternoclavicular
• B. Glenohumeral
• C. Acromioclavicular
• D. Atlantoaxial

Answer: (A)

The main idea here is that only one bony joint directly connects the axial skeleton to the appendicular skeleton—the sternoclavicular joint. This joint links the medial end of the clavicle (which belongs to the appendicular skeleton, forming part of the shoulder girdle) with the manubrium of the sternum (part of the axial skeleton). That single articulation is what ties the upper limb to the trunk. Other joints listed don’t provide that direct connection: the shoulder (glenohumeral) joint is between the humerus and the scapula (both part of the appendicular skeleton); the acromioclavicular joint is between the clavicle and the scapula (again both appendicular); and the atlantoaxial joints connect cervical vertebrae (both axial). Therefore, the sternoclavicular joint is the sole direct attachment between the two skeletal divisions.

The main idea here is that only one bony joint directly connects the axial skeleton to the appendicular skeleton—the sternoclavicular joint. This joint links the medial end of the clavicle (which belongs to the appendicular skeleton, forming part of the shoulder girdle) with the manubrium of the sternum (part of the axial skeleton). That single articulation is what ties the upper limb to the trunk.

Other joints listed don’t provide that direct connection: the shoulder (glenohumeral) joint is between the humerus and the scapula (both part of the appendicular skeleton); the acromioclavicular joint is between the clavicle and the scapula (again both appendicular); and the atlantoaxial joints connect cervical vertebrae (both axial). Therefore, the sternoclavicular joint is the sole direct attachment between the two skeletal divisions.