Describe synovial joints
- surrounded by a sleeve like capsule (the ‘joint capsule’) attached to the periosteum
- the inner layer of the joint capsule is formed by a synovial membrane which secretes synovial fluid
- the synovial fluid helps lubricate the joint and provides nourishment for the articulate cartilage on the bone ends
What are the six main types of synovial joints?
- gliding
- hinge
- pivot
- condyloid
- saddle
- ball and socket
Describe ‘gliding’ synovial joints
- a small gliding movement over a more or less flat surface
Eg: between the small carpal and tarsal bones of the hand and foot
Describe ‘hinge’ synovial joints
- possible in one plane only
Eg: elbow / knee
Describe ‘pivot’ synovial joints
- movement is purely rotational
Eg: between the radius / humerous
Describe ‘condyloid’ synovial joints
- movement occurring in two planes
- a circular motion (circumduction) can also be possible
Eg: at the first knuckle / the wrist
Describe ‘saddle’ joints
- similar to condyloid but surfaces are concave and convex, restricting circumduction
Eg: base of the thumb
Describe ‘ball and socket’ synovial joints
- movement can occur in all three planes
Eg: shoulder and hip
Describe the hip joint
- ball and socket
- top of the femur (ball) meets the pelvis (socket)
- six movements:
Flexion and extension
Abduction and adduction
Rotation and circumduction
Describe the knee joint
- hinge
- where the femur and tibia meet
- two movements:
Flex ion and extension
Describe the ankle
- hinge
- where the tibia and bones of the lower leg meet the talus bone of the ankle
- two movements:
Plantar flexion
Dorsi flexion
Describe the shoulder joints
- ball and socket
- where the humerus meets the scapula
- six movements:
Flexion and extension
Abduction and adduction
Internal and external rotation
Describe the elbow joints
- hinge
- where the humerus meets the ulna
- two movements:
Flexion and extension
Describe the wrist joints
- condyloid
- where the radius and ulna meet the carpals
- four movements:
Flexion and extension
Abduction and adduction
Briefly name and describe the three main types of joints
Immovable (fibrous)
- tightly joined by fibrous connective tissue
- eg: bones of the skull
Slightly moveable (cartilaginous)
- bones connected by more pliable cartilage
- eg: joints between them vertebrae separated by the cartilage of the inter-vertebral discs OR ribs to the sternum, allowing the ribcage to raise and lower
Freely moveable (synovial)
- ends of the bones are surrounded by a fibrous capsule containing synovial fluid
- eg: elbow or knee
