Joints and Articulations - · PDF file–Synovial Joints. Functions ... Hinge Joint...
Transcript of Joints and Articulations - · PDF file–Synovial Joints. Functions ... Hinge Joint...
Joints and Articulations:
Junctions between bones.
• Types/Categories
– Fibrous Joints
– Cartilaginous Joints
– Synovial Joints
Functions
• Bind parts of the skeleton.• Allow for bone growth.• Permit changes of skeleton
during childbirth.• Allow for movement.• Vary considerably in
structure and function.• Classified based on degree
of movement.AND/OR
• The type of tissue that bonds the bones together.
Fibrous Joints• Connect bones that are
very close to one another.
• A thin layer of connective tissue joins the bones together.
• No measurable movement occurs at this joint.
• Example: sutures between bones of the skull.
Cartilaginous Joints
• Use of hyaline cartilage to connect bone.
• Allows limited movement.
• Absorbs shock.
• Example: intervertebral discs.
Synovial Joints
• Most joints fit into this category.
• Permits free movement.
• Structurally complex.
• Ends of bones are covered with smooth cartilage = allows for gliding and prevents bones from rubbing together.
• Surrounds a joint capsule filled with fluid to lubricate joints.
• Some have flatened shock absorbing pads called meniscus.
• Some have a bursae that allows for tendons to glide smoothly over the joint.
Ball-and-Socket
• Bone with a rounded (ball-shaped) end that articulates with a cup-shaped cavity.
• WIDE range of motion
• Example: Shoulder and Hip
Condyloid Joint
• Oval shaped bone extension fits into a shallow cavity.
• Can move in different directions but NOT rotate.
• Example: between metacarpals (bone of palm) and phalanges (fingers).
Gliding Joint
• Articulations on an almost flat plane.
• Allow for sliding or twisting motion.
• Examples:
– Between carpal (wrist) and tarsal (ankle) bones.
– Sternum and ribs.
– Sacrum and pelvis
Hinge Joint
• Convex surface of one bone fits into concave surface of another bone.
• Resembles the hinge of a door.
• Examples:
– Joints of the phalanges
– Elbow
Pivot Joint
• Cylindrical surface of one bone rotates in the ring formed between another bone and a ligament.
• Permits rotation.
• Example:
– Radius and ulna
– Cervical vertebrae (neck) and skull.
Saddle Joint
• BOTH bone surfaces have both a concave and convex surface.
• Bone fits like a puzzle piece.
• Allows for a variety of movement.
• Example: bones between metacarpal (hand) and thumb.
Special Considerations
• Arthritis:inflammation of one or more joints that results in pain, swelling, stiffness, and limited movement
Special Considerations
• Arthrocentesis: removal of fluid from the joint capsule to alleviate pressure and swelling.
Special Considerations
• Arthrodesis: surgical union of a joint; fusing two or more bones together
Surgical Union of Lumbar
(lower back) Vertebrae.