Arthrology Flashcards
what are the functions of joints?
- to transmit forces
- enable and restrict movement
- accommodate growth e.g. endochondral ossification are temporary joints
What are the four structural classifications of joints?
- Bony
- Fibrous
- Cartilaginous
- Synovial
What are the three types functional categories of joints? explain each
- Synarthrosis - no movement - located where movement between bones must be prevented
- Amphiarthrosis - little movement - permits more movement than a synarthrosis but is much stronger than a freely movable joint - articulating bones are connected by collagen fibres or cartilage.
- Diarthrosis - free movement - in synovial joints
What is the name for a bony joint? Provide an example
Synostosis - created when two bones fuse together. e.g. frontal suture of the skull and epiphyseal lines of long bones.
What is the functional category of a synostosis?
Synarthrisis (no movement)
What are the structural types of fibrous tissue?
Suture, gomphosis, syndesmosis
Give a description of a suture joint
a synarthrotic joint located only between the joints of the skull. The edges of the bones are interlocked and bound together at the suture by dense fibrous connective tissue.
Give a description of a gomphosis joint
a synarthrosis that binds the teeth to bony sockets in the maxillae and mandible. The fibrous connection between a tooth and its socket is a periodontal ligament.
Give a description of a syndesmosis joint
an amphiarthrosis joint that connects two bones by a ligament. E.g. distal joint between tibia and fibula
What is the functional category of a syndesmosis?
amphiarthrosis - permits a small amount of movement
describe a synchondrosis
a rigid cartilaginous bridge between two articulating bones made of hyaline cartilage. it is a synarthrosis. e.g. costochondral joints between the costal cartilage and ribs.
what kind of joint is the joint between the two pubic bones?
a symphosis - made of fibrocartilage
Describe a symphosis joint
a joint where the articulating bones are connect by a wedge or pad of fibrocartilage. It is amphiarthrosis.
What kind of joints are are in the function category diarthrosis?
Synovial joints - they have free movement.
Describe a synovial joint and where you would find it?
permit a wider range of motion than other types of joints. Typically located at the ends of long bones such as those in upper and lower limbs.
What components would you find in a synovial joint?
- Fibrous joint capsule
- Synovial membrane
- Articular cartilage
- Joint cavity (contains synovial tissue)
what is the function of articular cartilage and where do you find it?
in synovial joints covering the articulating bones in the joint. It is made of hyaline cartilage. The articular cartilage is smooth and reduces friction. the two bones do not touch, a thin layer of synovial fluid separates them.
what is synovial fluid?
a clear viscous solution with the consistency of egg yolk or molasses. It is secreted from the synovial membrane to:
- lubricate and reduce friction
- nutrient distribution
- shock absorption
what is the role of a ligament in a joint?
Ligaments join bone to bone and prevent unwanted movment
what kind of joint is in the intercarpals/intertarsals?
gliding/plane
what is a gliding/plane joint?
where flat surfaces of bones meet and move in almost any direction. The movement is non-axial as there is no axis in these types of bones. e.g. between clavical and sternum.
what is a hinge joint?
a type of synovial joint where there is angular, monaxial movement in a single plane. e.g. elbow, knee, ankle, interphalangeal
what is a condylar/ellipsoid joint?
An angular, biaxial joint that has an oval articular face nestled within a depression on the opposing surface. e.g. metacarpophalangeal joints (knucles) radiocarpal
What is a saddle joint?
Angular, biaxial joints that have complex articular faces that fit together like a rider in a saddle. Each face is concave along one axis and convex along another e.g. carpometacarpal (thumb)
what is a pivot joint?
a rotational, monaxial joint that only allows rotation. e.g. antanto-axial joint (c1 and c2) and proximal radio-ulnar joint.
what is a ball and socket joint?
an angular, multiaxial joint that allows circumduction, and rotation. The round head od one bone rests within a cup-shaped depression in another. e.g. shoulder, hip
what kind of joint is the temporomandibular joint?
a modified hinge - an intra-articular disc in this joint created two joint spaces. In the superior space the joint glides and the hinge action is in the inferior joint space.
what are examples of modified hinges?
temperomandibular joint and tibiofemoral joint
list the synovial joints in order of least to most movement
- gliding/plane
- hinge
- pivot
- condylar
- saddle
- ball and socket
what kinds of joints are amphithroses?
symphysis (cartilaginous), syndesmosis (fibrous)
which joints are non-axial?
plane/gliding joints
which joints are uniaxial?
hinge, pivot
which joints are biaxial?
condylar, saddle
