Clavicle and Ear bones By,M. Thiru murugan Shoulder girdle (or) Pectoral girdle: The pectoral girdle or shoulder girdle is where the arms attach to the axial skeleton. It consist clavicle & scapula Clavicle - 2 (collarbone): The clavicle is located between the ribcage (sternum) and the shoulder blade (scapula). It is the bone that connects the arm to the body. Attaches medially to manubrium of sternum & laterally to scapula, prevents shoulder dislocation. The clavicle is a slender bone with an ‘S’ shape. It can be divided into a sternal end, a shaft and an acromial end. Sternal (medial) End: It contains a large facet – for articulation with the manubrium of the sternum at the sternoclavicular joint. Shaft: The shaft of the clavicle acts a point of origin and attachment for several muscles - deltoid, trapezius, subclavius, pectoralis major, sternocleidomastoid and sternohyoid. Acromial (lateral) End: it has a small facet for articulation with the acromion of the scapula at the acromioclavicular joint. It also serves as an attachment point for two ligaments: Conoid tubercle – attachment point of the conoid ligament & Trapezoid line – attachment point of the trapezoid ligament. Ear bones (6): Bones of the inner ear (or) auditory ossicles, Inside the temporal bone are the 3 smallest bones of the body: Malleus (one in each ear) Incus (one in each ear) Stapes or stirrup (one in each ear - this is the smallest bone in the body) These three bones articulate with each other and transfer vibrations from the tympanic membrane to the inner ear.

1. Clavicle and Ear bones

2. • Shoulder girdle (or) Pectoral girdle:
• The pectoral girdle or shoulder girdle is where the arms attach to
the axial skeleton. It consist clavicle & scapula
• Clavicle - 2 (collarbone):
• The clavicle is located between the ribcage (sternum) and the
shoulder blade (scapula). It is the bone that connects the arm
to the body.
• Attaches medially to manubrium of sternum & laterally to
scapula, prevents shoulder dislocation.
• The clavicle is a slender bone with an ‘S’ shape. It can be
divided into a sternal end, a shaft and an acromial end.
• Sternal (medial) End: It contains a large facet – for
articulation with the manubrium of the sternum at
the sternoclavicular joint.

3. • Shaft: The shaft of the clavicle acts a point of origin and
attachment for several muscles - deltoid, trapezius, subclavius,
pectoralis major, sternocleidomastoid and sternohyoid.
• Acromial (lateral) End: it has a small facet for articulation with
the acromion of the scapula at the acromioclavicular joint. It also
serves as an attachment point for two ligaments: Conoid
tubercle – attachment point of the conoid ligament & Trapezoid
line – attachment point of the trapezoid ligament.
Clavicle: Shaft

4. Ear bones (6):
• Bones of the inner ear (or)
auditory ossicles, Inside the
temporal bone are the 3
smallest bones of the body:
1. Malleus (one in each ear)
2. Incus (one in each ear)
3. Stapes or stirrup (one in
each ear - this is the
smallest bone in the body)
• These three bones articulate
with each other and transfer
vibrations from the tympanic
membrane to the inner ear.