Lecture 9 cont Articulations and Joints

A comprehensive set of practice flashcards covering joint structure, classifications, movements, selected joints, injuries, and common disorders based on the provided lecture notes.

What is a joint (articulation) and what does it connect?

A joint is a point of contact between two or more bones, between cartilage and bone, or between teeth and bone.

How are joints classified structurally?

Joints are structural classified as fibrous, cartilaginous, or synovial.

How are joints classified functionally?

Joints are functional classified as synarthroses (no movement), amphiarthroses (little movement), or diarthroses (freely moveable).

Name the three fibrous joint types and give a key example for each.

Sutures (dense fibrous CT; e.g., lambdoid suture), syndesmoses (denser fibrous CT; e.g., gomphosis), interosseous membranes (between radius and ulna or tibia and fibula).

What are the two main types of cartilaginous joints and their characteristics?

Synchondroses: hyaline cartilage; little to no movement after growth (epiphyseal plates, first sternocostal joint). Symphyses: fibrocartilage with hyaline, slight movement (pubic symphysis, intervertebral joints).

Provide examples of synchondroses and symphyses.

Synchondroses: epiphyseal plates; first sternocostal joint. Symphyses: pubic symphysis; joints between vertebrae (intervertebral discs).

What defines a synovial joint?

A synovial joint has a synovial cavity, articular cartilage, an articular capsule, ligaments, and synovial fluid; it is freely movable.

What are the two layers of the articular capsule in a synovial joint?

Fibrous membrane (dense irregular CT) and synovial membrane (areolar tissue, sometimes adipose).

What is the function of synovial fluid in a synovial joint?

Synovial fluid lubricates the joint, nourishes cartilage, absorbs shocks, and removes wastes.

What are bursae and tendon sheaths?

Bursae are sac-like structures filled with synovial fluid that cushion movement; tendon sheaths are tube-like bursae surrounding tendons with high friction.

What are angular movements?

Movements that change the angle between body parts, including flexion, extension, abduction, adduction, and circumduction.

What is rotation in joint movement?

Turning a bone around its own axis (medial/internal or lateral/external rotation).

List some special movements and give one example for each.

Pronation (radius over ulna) and supination (radius and ulna parallel); dorsiflexion and plantar flexion; inversion and eversion; protraction and retraction; elevation and depression; opposition.

What are condyloid, saddle, and ball-and-socket joints in terms of movement?

Condyloid: biaxial (flexion/extension, abduction/adduction, limited circumduction); Saddle: similar movements as condyloid with a different articulation; Ball-and-socket: triaxial (multiaxial) movements.

Give examples of each synovial joint type: condyloid, saddle, and ball-and-socket.

Condyloid: radiocarpal joint (wrist). Saddle: carpometacarpal joint of the thumb. Ball-and-socket: shoulder (glenohumeral) and hip joints.

What factors affect contact and range of motion at synovial joints?

Bone structure/shape, ligament strength, muscle arrangement and tension, contact of soft parts, hormones, and disuse.

Describe the Temporomandibular Joint (TMJ) and its movement during mouth opening.

The TMJ is between the temporal bone and the mandible with an articular disc; during mouth opening the mandibular condyle moves forward and hinges downward from the mandibular fossa onto the articular tubercle.

What is the Glenohumeral (shoulder) joint and what features support it?

A ball-and-socket joint with the widest range of motion; it has a loose articular capsule supported by ligaments and the rotator cuff muscles.

Describe the elbow joint anatomy as shown in the notes.

The elbow involves the humerus and ulna with the trochlea, articular cartilage, and synovial cavity; it has associated structures such as olecranon bursa and ligaments within the articular capsule.

Describe the hip joint anatomy and key stabilizing ligaments.

The hip is a ball-and-socket joint formed by the head of the femur and the acetabulum with an articular capsule, acetabular labrum, and ligaments including iliofemoral, pubofemoral, and ischiofemoral ligaments.

What is a sprain and what is a strain? How do they differ in tissue affected?

Sprain: injury to ligaments (bone-to-bone) due to joint being forced beyond its normal range; Strain: injury to muscles or tendons (muscle-to-bone) from overstretching or tearing.

What is RICE and when is it used?

RICE stands for Rest, Ice, Compression, Elevation; used for sprains and strains to reduce pain and swelling.

What is bursitis?

Inflammation of the bursae, the fluid-filled sacs around joints; example: tennis elbow.

What are common TMJ disorders and their treatments?

TMJ disorders are often due to bruxism, excessive gum-chewing, stress or trauma; treatments include night guards, splint therapy, Botox, and sometimes surgical realignment of the disk.

Differentiate gout, osteoarthritis, and rheumatoid arthritis in cause and typical joints affected.

Gout: metabolic uric acid crystals in joints (often big toe); OA: wear-and-tear degeneration of articular cartilage in weight-bearing joints; RA: autoimmune inflammatory disease affecting small joints and is often symmetrical.

What treatments are common for arthritis?

NSAIDs; disease-modifying drugs for RA (e.g., methotrexate), biologics; lifestyle changes; physical therapy; in severe OA/RA, joint replacement (knee or hip).

What is the memory trick to distinguish sprain from strain?

Sprain = ligament; Strain = tendon/muscle.