Joint Classification Flashcards
Fibrous Joints
- Dense fibrous connective tissue
- Structure : ligaments
- Function : limiting movement for stability
e.g Cranial sutures
Cartilaginous Joints
- Some movements
- Tissue : fibrocartilage
- Various structures with specific functions
e.g. intervertebral disc
Synovial Joints
- Free moving
- Most limb joints
- Amount and direction of movement is determined by joint structure
Synovial Joint Structure
- Synovial Membrane (lines joint capsule)
- Joint Capsule (layer of connective tissue around joint)
- Joint Cavity (potential space)
- Articular Cartilage (covers bone ends)
- Ligaments (hold bone together restricts movement)
Articular Cartilage in Synovial Joint
- Covers bone ends where they move/articulate
- Allows for smooth, frictionless movement
Joint Capsule in Synovial Joint
- Outer layer of DFCT (very strong)
- Inner layer of synovial membrane (secretes synovial fluid)
- Holds bones together
- Tight and thick where more support required
- Loose where movement is allowed
Capsular Ligaments in Synovial Joints
More support is required in some joints e.g. collateral ligaments of knee
Present in MCL (medial collateral ligament) which connects femur to tibia and restricts abduction and LCL (lateral collateral ligament) which connects femur to fibula and restricts adduction
Intracapsular ligaments in Synovial Joints
Additional bands of DFCT located internally to capsule holds bones together
In cruciate ligaments of knee:
ACL (anterior to tibia posterior to femur), restricts posterior displacement
PCL (posterior to tibia anterior to femur), restricts anterior displacement
Fibrocartilaginous structures in synovial joints
- Small structures made of fibrocartilage that fill space and provide cushioning/shock absorption and deepen articulations
- Meniscus in knee are an example
Range of Movement (ROM)
The type and amount of movement is determined by the structure of the joint : bone end shape, ligament location and length and body surface contact
Plane Joint
- Multiaxial
- Sliding and gliding
- Inter carpal and tarsal joints
Hinge Joint
- Uniaxial
- Flexion and extension
- Elbow
Pivot Joint
- Uniaxial
- Movement is rotation
- C1-C2 vertebrae
Condylar Joint
- Biaxial
- Flexion and extension
- Rotation (when flexed)
- Knee
Ellipsoid Joint
- Biaxial
- Flexion and extension
- Abduction and adduction
- Circumduction
NO ROTATION - Wrist joint