Untitled Flashcards Set

1. Joint Classification

Joints (articulations) are categorized by structure (based on the connective tissue) and function (range of movement).

Structural Classifications:

• Fibrous Joints: Bones connected by dense connective tissue; no joint cavity.

• Cartilaginous Joints: Bones connected by cartilage; limited movement.

• Synovial Joints: Have a fluid-filled cavity allowing significant movement.

Functional Classifications:

• Synarthrosis: Immovable joints.

• Amphiarthrosis: Slightly movable joints.

• Diarthrosis: Freely movable joints (primarily synovial).

2. Joint Types and Examples

A. Fibrous Joints

1. Sutures

   • Found between skull bones (e.g., coronal suture).

   • Immovable (synarthrosis).

2. Syndesmoses

   • Bones connected by ligaments (e.g., between the radius and ulna).

   • Slightly movable (amphiarthrosis).

3. Gomphoses

   • Peg-in-socket joints (e.g., teeth in alveolar sockets).

   • Immovable (synarthrosis).

B. Cartilaginous Joints

1. Synchondroses

   • Bones joined by hyaline cartilage (e.g., epiphyseal plates in children).

   • Immovable (synarthrosis).

2. Symphyses

   • Bones joined by fibrocartilage (e.g., pubic symphysis, intervertebral discs).

   • Slightly movable (amphiarthrosis).

C. Synovial Joints

• Freely movable joints with six types based on movement.

1. Plane (Gliding) Joints

   • Allow sliding or gliding movements.

   • Examples: Intercarpal and intertarsal joints.

2. Hinge Joints

   • Allow flexion and extension.

   • Examples: Elbow (humeroulnar joint), knee (modified hinge), interphalangeal joints.

3. Pivot Joints

   • Allow rotational movement around a single axis.

   • Examples: Atlantoaxial joint (C1-C2), proximal radioulnar joint.

4. Condyloid (Ellipsoid) Joints

   • Allow movement in two planes (flexion/extension, abduction/adduction).

   • Examples: Wrist (radiocarpal joint), metacarpophalangeal joints.

5. Saddle Joints

   • Allow movement in two planes; bones fit together like a rider on a saddle.

   • Examples: Thumb (carpometacarpal joint of the first digit).

6. Ball-and-Socket Joints

   • Allow movement in multiple axes and planes.

   • Examples: Shoulder (glenohumeral joint), hip (acetabulofemoral joint).

3. Joints by Body Region

Head

• Skull sutures (fibrous).

• Temporomandibular joint (TMJ) - Synovial, hinge, and gliding.

Vertebral Column

• Intervertebral joints:

  • Between vertebral bodies: Symphyses (cartilaginous).

  • Between vertebral arches: Synovial (plane).

Upper Limb

• Shoulder (glenohumeral joint): Synovial, ball-and-socket.

• Elbow: Synovial, hinge.

• Radioulnar joints: Synovial, pivot.

• Wrist: Synovial, condyloid.

• Finger joints: Synovial, hinge.

Lower Limb

• Hip (acetabulofemoral joint): Synovial, ball-and-socket.

• Knee: Synovial, hinge (with some rotation).

• Ankle: Synovial, hinge.

• Toe joints: Synovial, hinge.

Thorax

• Sternocostal joints: Synchondroses (cartilaginous, first rib) or synovial (remaining ribs).