Types of Joint Movements

The Standard SAP2. Students will analyze the interdependence of the integumentary, skeletal, and muscular systems as these relate to the protection, support and movement of the human body. b. Explain how the skeletal structures provide support and protection for tissues, and function together with the muscular system to make movements possible.

Essential Question What are some examples of the movements “PROTRACTION” and ”RETRACTION”?

Movement in the Shoulder Girdle Very free moving because Only attaches at one point to axial skeleton Loose attachment of scapula allows it to slide Glenoid cavity very shallow

Shoulder Girdle Also called pectoral girdle Composed of only two bones Clavicle Scapula

Humerus The 3rd bone of the shoulder joint

Clavicle Collar bone Double-curved Attaches medially to manubrium of sternum Attaches laterally to scapula Acts as a brace, keeping arm away from thorax Also prevents shoulder dislocation

Scapula Main function is attachment of shoulder Major point of muscle attachment for movement of arms Weakly attached to thorax, so moves easily

Glenoid Cavity Socket of arm joint Shallow Allows for great range of motion Also dislocates easily

Sternoclavicular Joint

Acromioclavicular Joint

Glenohumeral Joint

Fractures

Simple Fracture Also called closed fracture Bone breaks cleanly, and does not penetrate skin. Little chance of infection

Compound Fracture Bone breaks completely Bone ends protrude through skin Major chance of serious bone infection

Comminuted Fracture Bone breaks into many fragments Common in elderly

Compression Fracture Bone is crushed Common in porous bones Especially common in vertebrae of osteoporosis patients

Depression fracture Broken bones are forced inward Common in skull fractures

Impacted Fracture Broken bone ends are forced into each other Common in falls (ie. From ladder) where person attempts to break their fall

Spiral Fracture Occurs from excessive twisting force on bone Common in sports injuries

Greenstick Fracture Bone breaks incompletely Common in children due to more collagen in bones

Repairing Fractures Closed reduction = bones are eased back into alignment and “reset” Open reduction = bones are surgically reset using screws or wires After either, a cast is usually applied to immobilize the bone; healing begins