Lecture 2 Joint and Muscle Function Flashcards
What is Wolff’s Law?
Bones adapt based on the stress or demands placed on them.
How are joints classified?
By structure (fibrous, cartilaginous, synovial) and by movement (synarthrosis, amphiarthrosis, diarthrosis).
What are fibrous joints?
Joints joined by fibrous connective tissue allowing little or no movement, like sutures in the skull. SYNARTHROSIS MOVEMENT
What is a syndesmosis joint?
A joint joined by an interosseous ligament, like between the radius and ulna.
What is a high ankle sprain?
An injury causing hypermobility of the syndesmosis joint between the tibia and fibula.
What are cartilaginous joints?
Joints connected by fibrocartilage or hyaline cartilage allowing some movement, like intervertebral joints.
What are synovial joints?
Freely movable joints with a joint cavity, like the elbow and knee.
What is the function of synovial fluid?
To lubricate joint surfaces, reduce friction, and provide nutrients to cartilage.
What is rheumatoid arthritis?
A progressive autoimmune disease causing hypertrophy of the synovial lining and damage to cartilage.
What structures improve joint stability?
Menisci, labrums, and discs.
What is the function of ligaments?
To align joint surfaces and guide or restrain motion.
What do tendons do?
Transmit forces from muscles to bones to produce motion.
What are bursae?
Connective tissue sacs that reduce friction between moving structures.
What is osteokinematics?
The movement of bones around a joint, described by plane and axis.
What is arthrokinematics?
The movement of joint surfaces, including roll, slide, and spin.
What is the convex-concave rule?
If a convex surface moves on a concave surface, roll and glide occur in opposite directions, and vice versa.
What is joint play?
The small, passive movements allowed in a joint, like roll, glide, and spin.
What is the close-packed position of a joint?
When joint surfaces are fully congruent, ligaments are taut, and the joint is most stable.
What is the loose-packed position of a joint?
When joint surfaces are incongruent, ligaments are lax, and passive movement is easiest.
What is end-feel?
The sensation felt at the end of a joint’s passive range of motion.
What are the types of end-feel?
Soft (muscle approximation), firm (capsular/ligamentous tension), hard (bone contact).
What is hypermobility?
Joint movement that exceeds normal limits.
What is hypomobility?
Joint movement that is less than normal.
What is the primary function of fibroblasts?
To synthesize the extracellular matrix of connective tissues.
