Biomechanics of Articular Cartilage

These flashcards cover essential concepts from the Biomechanics of Articular Cartilage lecture, focusing on joint types, cartilage functions, treatment of osteoarthritis, and principles of joint stability and flexibility.

What are the three categories of joints?

Synarthroses, Amphiarthroses, Diarthroses.

What is articular cartilage?

A protective layer of dense white connective tissue covering the articulating bone surfaces.

What is the primary function of articular cartilage?

To reduce contact stress and regulate lubrication in synovial joints.

What does joint stability refer to?

The ability of a joint to resist abnormal displacement of the articulating bones.

What is osteoarthritis?

A common, degenerative disease of articular cartilage characterized by pain, swelling, and joint inflammation.

What are the key components that contribute to joint stability?

A closely reciprocating match of articulating bone surfaces, a strong array of ligaments and muscle tendons, and absence of muscle fatigue.

What are the two classifications of cartilage?

Articular cartilage (hyaline) and fibrocartilage.

What are the types of synovial joints?

Gliding, Hinge, Pivot, Condyloid, Saddle, and Ball-and-socket.

What is the role of synovial fluid?

To provide lubrication inside the articular capsule.

What is the composition of articular cartilage?

70 to 85% water, 60 to 70% collagen, and proteoglycans like chondroitin sulfate.

What is the function of fibrocartilage?

To distribute loads over joint surfaces and improve the fit of articulating surfaces.

What do the terms dynamic flexibility and static flexibility mean?

Dynamic flexibility refers to active movement through range of motion; static flexibility involves passive movement.

What does PNF stand for?

Proprioceptive Neuromuscular Facilitation.

What is the purpose of active stretching?

To develop tension actively in antagonist muscles.

How much water is present in articular cartilage?

70 to 85% of wet weight.

What is a syndesmosis joint?

A fibrous joint where dense tissue binds bones together, allowing limited movement.

What is a synchondroses joint?

A cartilaginous joint held together by a thin layer of hyaline cartilage.

What is the role of tendons?

To connect muscles to bones.

What is the role of ligaments?

To connect bones to other bones.

What is the mechanism of ball-and-socket joints?

Permits rotation in all three planes of movement.

What type of joint is the knee considered?

A synovial joint.

What is active static stretching?

Holding a position near the extreme joint range of motion for about 30 seconds.

What is the typical treatment for osteoarthritis?

Includes non-surgical options like drug therapy and lifestyle changes, and surgical options like joint replacement.

What is the effect of excessive mechanical stress on articular cartilage?

It can promote the development of osteoarthritis.

What is joint flexibility?

The relative ranges of motion allowed at a joint in different directions.

What are the effects of static stretching?

Maintaining a slow, controlled stretch over time, usually for 30 seconds.

What does a goniometer measure?

Range of motion (ROM) during joint movement.

What is the primary difference between active and passive stretching?

Active stretching is initiated by the individual whereas passive stretching involves an external force.

What is the iliotibial band?

A strong, thickened region of fascia that contributes to knee stability.

What is the main structural feature of articular cartilage?

It is fluid-saturated and dense, structured to bear loads and minimize friction.

What classifies uniaxial joints?

Joints that allow movement around one axis only.

What is the near maximum joint stability position called?

The close-packed position.

What are bursae?

Small capsules filled with synovial fluid that cushion structures in joints.

What is shock absorption in the context of articular fibrocartilage?

To protect and cushion the joint from impacts.

What are the treatment options for osteoarthritis?

Non-surgical treatments include drug therapy and physical therapy; surgical options include joint replacement.

What type of cartilage is found in the pubic symphysis?

Fibrocartilage.

What are some examples of diarthroses joints?

Knee, hip, and shoulder joints.

What is the composition of fibrocartilage?

Matrix of collagen and proteoglycans that supports and absorbs shock.

What characterizes amphiarthroses joints?

Joints allowing slight movement, connected with cartilage.

What is the most common symptom of osteoarthritis?

Pain and stiffness in the joint.

What can excessive mechanical stress lead to?

The degeneration of articular cartilage and development of osteoarthritis.

What are the major functions of synovial fluid?

Lubrication of joints and nutrient transport for the cartilage.

What is the structure that surrounds a synovial joint?

The articular capsule.

What is the major concern when dealing with joint flexibility?

To increase or maintain a joint's range of motion.