Anatomy Ch. 8

Synovial

All of these are _________ joints. -Knee joint: Composed of the femoropatellar joint and the tibiofemoral joint. -Shoulder joint: Glenohumeral joint. -Elbow joint -Hip joint -Temporomandibular joint

Flexion

Angular joint movement. Bending movement usually on the sagittal plane that decreases the angle of the joint and brings the articulating bones closer together. -Ex: Bending head forward on the chest, bending body trunk or the knee from a straight to an angled position, arm is flexed when arm is lifted in anterior direction

Extension

Angular joint movement. Involved movement along the sagittal plane that increases the angle between articulating bones. Typically straightens a flexed limb or body part. -Ex: Straightening a flexed neck, body trunk, elbow, or knee.

Abduction

Angular joint movement. Movement of a limb away from the midline or median plane, along the frontal plane. -Ex: Spreading fingers or toes apart, moving arm away from body.

Adduction

Angular joint movement. Movement of a limb toward the body midline. -Ex: Moving arm towards body.

Circumduction

Angular joint movement. Moving a limb so it describes a cone in space. Distal end of the limb moves in a circle, while the point of the cone (shoulder or hip joint) is more or less stationary. Consists of flexion, abduction, extension, and adduction. Quickest way to exercise the muscles that move the hip and shoulder ball-and-socket joints. -Ex: Pitcher winding up to throw

Synovial

Articulating bones are separated by a fluid-containing joint cavity. Permits substantial freedom of movement. All are freely moveable (diarthroses). Nearly all joint of the limbs and most of the body fall into this class.

Cartilaginous

Articulating bones are united by cartilage. Lack a joint cavity and are not highly moveable.

Saddle joint

Biaxial movement. Adduction and abduction. Flexion and extension. Articulate surfaces both concave and convex. Found in carpaometacarpal joints of the thumb.

Condylar joint

Biaxial movement. Flexion and extension. Addunction and abduction. Found in metacarpophalangeal joints (knuckle) wrist joints.

Dislocation

Bones are forced out of alignment.

Fibrous

Bones are joined by fibrous tissue, namely dense fibrous CT, and no joint cavity is present. Amount of movement depends on the length of the CT fibers uniting the bones. Most are immovable.

Symphyses

Bones united by fibrocartilage. "growing together." Since fibrocartilage is compressible and resilient, it acts as a shock absorber and permits a limited amount of movement in the joint. Hyaline cartilage also is present in the form of articular cartilages on the bony surfaces. Amphiarthrotic joints designed for strength with flexibility. Slightly moveable. Found in axial skeleton. -Example: Pubic symphysis, vertebrae (body of vertebrae with intervertebral disc)

Synchondroses

Bones united by hyaline cartilage. "Junction of cartilage." All are synarrthrotic. Immobile. -Example: epiphyseal plates in the long bones of children -Example: Immovable joint between the costal cartilage of the first rib and the manubrium of the sternum.

Rheumatoid arthritis

Chronic inflammatory disorder with an insidious onset. Occurs 30-50 years old. Affects three times as many women as men. In early stages, joint tenderness and stiffness are common in the fingers, wrists, ankles, and feet. It is variable and marked by flare-ups. May also include anemia, osteoporosis, muscle weakness, and cardiovascular problems. It's an autoimmune disease where the body's immune system attacks its own tissue.

Articular surfaces

Component contributing to joint stability. Minor role. Shape determine what movements are possible at a joint. Ball-and-socket joint of the hip joint.

Ligaments

Component contributing to joint stability. Number and location. Unite the bones and prevent excessive or undesirable motion. The more ligaments a joint has, the stronger the joint.

Muscle tendons

Component contributing to joint stability. Those that cross the joint are the most important stabilizing factor. These are kept taut at all times by the tone of their muscles. Important in reinforcing shoulder and knee joints and arches of the foot.

Tendon sheaths

Elongated bursa wrapped completely around tendon subjected to friction. Surround tendon. Common to see injuries here.

Fibrous

External layer of the articular capsule. Dense irregular CT. Supporting structure. Move across planes.

Sutures

Fibrous joint. "seams" that occur only between bones of the skull (sutures). The wavy articulating bone edges interlock, and the junction is completely filled by a minimal amount of very short CT fibers that are continuous with the periosteum. Result is nearly rigid splices that knit the bones together, yet allow the skull to expand as the brain grows during youth. During middle age, fibrous tissue ossifies and skull bones fuse into a single unit. Immobile (synarthrosis).

Syndesmoses

Fibrous joint. Bones are connected exclusively by ligaments, cords or bands of fibrous tissue. The connecting fibers vary in length. Amount of movement depends on the length of the connecting fibers. Short fibers=little or no movement. Long fibers=large amount of movement is possible (amphiarthrosis). -Example: fibula and tibia connected by a ligament

Gomphoses

Fibrous joint. Peg-in-socket fibrous joint. "nail" or "bolt." Refers to the way teeth are embedded in their sockets. Periodontal ligament holds tooth in socket. Immobile.

Plane joint

Flat articular surfaces. Nonaxial movement. Gliding. Found in hands and feet (carpals, tarsals) such as intercarpal joints, intertarsal joints, joints between vertebral articular surfaces.

Diarthroses

Freely moveable

Articular cartilage

Hyaline cartilage. Prevents crushing of bone ends. Glide seamlessly across each other.

Synarthrosis

Immovable

Angular

Increase or decrease the angle between two bones. May occur in any plane of the body and include flexion, extension, hyperextension, abduction, adduction, and circumduction (cross all different planes; windmill, arm).

Synovial Membrane

Inner layer of the articular capsule. Loose CT. Produces/secretes synovial fluid. Capsule lines with this layer.

Elevation

Lifting a body part superiorly. Shrugging shoulders. Mouth closed.

Sprain

Ligaments are stretched or torn. Common in lumbar spine, knee, and ankle.

Osteoarthritis

Most common chronic arthritis. "Wear-and-tear arthritis." Degeneration of articular cartilage (bone on bone contact). Leads to thickening of subchondral bone (abnormal formation of new bone ("bone spurs:" Dehabilitating pain)). More women are affected than men and usually occurs in older women. More cartilage is destroyed than replaced.

Uniaxial

Movement in one plane

Multiaxial

Movement in or around all three planes of space and axes.

biaxial

Movement in two planes.

Eversion

Movement of the foot. Sole faces laterally.

Inversion

Movement of the foot. Sole of the foot turns medially.

Supination

Movements of the radius around the ulna. "Turning backward." Anatomical position. Palm faces anteriorly or superiorly. Radius and ulna are parallel.

Pronation

Movements of the radius around the ulna. "Turning forward." Palm faces posteriorly or inferiorly. Radius rotates over ulna.

Depression

Moving the elevated part inferiorly. During chewing, the mandible is depressed when open.

Ball and socket joint

Multiaxial movement. Flexion and extension. Adduction and abduction. Rotation. Spherical head (ball). Found in shoulder joints and hip joints.

Strain

Muscles are stretched or torn.

hinge

Name the type of synovial joint of the: Humeroulnar

pivot

Name the type of synovial joint of the: Radioulnar

hinge

Name the type of synovial joint of the: Temporomandibular

hinge

Name the type of synovial joint of the: Tibiofemoral

ball and socket

Name the type of synovial joint of the: humeroscapular

Protraction

Nonangular anterior movement in a transverse plane. Mandible protracted when you jut out your jaw.

Retraction

Nonangular posterior movement in a transverse plane. Mandible retracts when you bring your jaw back in.

Gliding

Plane joints (nonaxial) Occurs when one flat bone surface glides or slips over another (back and forth and side to side) without appreciable angulation or rotation. -Ex: Intercarpal and intertarsal joints, between flat articular processes of the vertebrae. Wrist and vertebral. Ulnar and radial deviation.

Bursae

Sacs lined with synovial membrane-contain synovial fluid. Reduce friction where ligaments, muscles, skin, tendons, or bones rub together. Cushions "pillow packet."

Opposition

Saddle joint between metacarpal 1 and the trapezium allow this movement of the thumb. When you touch your thumb to the tips of the other fingers on the same hand. Makes human hands such a fine tool for grasping and manipulating objects.

Amphiarthroses

Slightly moveable

Nonaxial

Slipping movements only, since there is not axis around which movement can occur.

Joint cavity

Small, fluid-filled potential space in joint. Contains synovial fluid

Synostoses

Suture. "bony junctions." Closed sutures that happen in middle age.

Bursa

Synovial fluid-filled sack, found outside a joint capsule, that allows tendons (or other structures) to slide freely over bones.

Rotation

Turning of a bone around its own long axis. Only movement allowed between the first two cervical vertebrae and common at the hip and shoulder joints. Directed toward or away from the midline. -Ex: Medial rotation of the thigh toward the median plane of the body.

Articular capsule

Two layers. -External Fibrous layer: Dense irregular CT. Supporting structure. Move across planes. -Inner Synovial membrane: Loose CT. Produces/secretes synovial fluid. Capsule lines with synovial membrane.

Hinge joint

Uniaxial movement. Flexion and extension. Cylinder and trough. Found connecting humerus and ulna (elbow joint), interphalangeal joints.

Pivot joint

Uniaxial movement. Rotation. In the ulna and radius: Sleeve (bone and ligament) Axle (rounded bone). Found in proximal radioulnar joints, atlantoaxial joints

Plantar flexion

Up-and-down movements of the foot at the ankle. Depressing the foot (pointing the toes). Corresponds to wrist flexion.

Dorsiflexion

Up-and-down movements of the foot at the ankle. Lifting the foot so that it's superior surface approaches the shin. Corresponds to wrist extension.

Cartilage tear

Very common. Menisci tears when subject to compression and shear stress stimutaneously.

Synovial fluid

Viscous, slippery filtrate of plasma and hyaluronic acid. Lubricates and nourishes articular cartilage. Contains phagocytic cells (immune cells) to remove microbes and debris

Synovial

articular cartilage, joint cavity, articular capsule, synovial fluid, reinforcing ligaments, nerves, and blood vessels

Fibrous

suturs, syndesmoses, gomphoses (teeth)

Cartilaginous

synchondroses, symphyses (pubic symphesis)