The Appendicular skeleton Appendage = add on = limb Why do I even want an appendicular skeleton? Appendicular Skeleton • The appendicular skeleton is made up of the bones of the limbs and their girdles • Pectoral girdles attach the upper limbs to the body trunk • Pelvic girdle secures the lower limbs • What the heck is a girdle? • A girdle usually means a belt like structure surrounding the body Pectoral Girdles • The pectoral girdles consist of the anterior clavicles and the posterior scapulae • They attach the upper limbs to the axial skeleton • The way its set upallows for maximum movement • They provide attachment points for muscles that move the upper limbs Maximum movement good or bad? You tell me! Good • Lots of flexibility! – Lots o’ movement Bad • Poorly reinforced – Lots o’ dislocations Glenohumerol joint Figure 7.22a Clavicles (Collarbones) • Slender, “doubly curved” long bones lying across the superior thorax – Curve makes sense! • attachment points for muscles • act as braces to hold the scapulae and arms out laterally - away from the body Clavicle You’ve got: • The acromial (lateral) end articulates with the scapula, • The sternal (medial) end articulates with the sternum (manubrium @ what notch?? • Conoid tubercle – near acromial end – ligaments attach collar bone to 1st rib Clavicles (Collarbones) Figure 7.22b, c Scapulae (Shoulder Blades) • Moves quite freely across thorax • Triangular, flat bones lying on the dorsal surface of the rib cage – between the second and seventh ribs • Scapulae have three borders and three angles – Superior – shortest & sharpest – Medial – parallel to vertebral column – Lateral – runs into armpit! (glenoid cavity) Angles – superior, lateral, inferior Scapula • Anterior view = boring! • Posterior view includes 1. Spine – palpated easily! 2. Acromion – region we learned (shoulder point) a) Articulates with clavicle acromioclavicular joint 3. Coracoid process – bicep brachialis anchored here 4. Suprascapular notch – nerve passage helps bound coracoid process – (laterally bounded by glenoid cavity) 5. Infraspinous and 6. supraspinous fossae • Major markings include the suprascapular notch, the supraspinous and infraspinous fossae, the spine, the acromion, and the coracoid process Scapulae (Shoulder Blades) Figure 7.22d Scapulae (Shoulder Blades) Figure 7.22e Scapulae (Shoulder Blades) Figure 7.22f