Types of Joints and Their Functions

This set of flashcards covers the key concepts related to types of joints, their structures, functions, and movements as discussed in the lecture notes.

Bony Joint (Synostosis)

An immovable joint formed when the gap between two bones ossifies, resulting in a single bone.

Fibrous Joint

A joint made of fibrous tissue that is immovable or slightly movable, closely binding the bones of the skull.

Sutures

Immovable fibrous joints that connect bones of the skull.

Gomphoses

Fibrous joint that attaches a tooth to its socket, held in place by the periodontal ligament.

Syndesmosis

A fibrous joint where two bones are bound by longer collagenous fibers, allowing more mobility.

Synchondroses

Joints where bones are united by hyaline cartilage, such as the epiphyseal plate.

Symphysis

A cartilaginous joint where two bones are joined by fibrocartilage, allowing limited movement.

Synovial Joint

A type of joint characterized by a joint cavity filled with synovial fluid, allowing for free movement. Articular cartilage and reinforcing ligaments 

Articular Cartilage

Layer of hyaline cartilage covering the surfaces of bones in a synovial joint, protecting them.

Synovial Fluid

A slippery lubricant found in the joint cavity that nourishes articular cartilage and reduces friction.

Meniscus

Fibrocartilage in the knee that absorbs shock and pressure.

Bursae

Sacs of synovial fluid that reduce friction in synovial joints.

Joint (Articular) Cavity

Space that separates the articular surfaces of the bones in a synovial joint.

Range of Motion (ROM)

The degree through which a joint can move, influenced by the structure of articulating surfaces.

Nonaxial Movement

Movement that occurs with slipping motions only, such as in plane joints.

Uniaxial Movement

Movement that occurs in one plane, exemplified by hinge joints like the elbow.

Biaxial Movement

Movement that occurs in two planes, such as in condylar joints like the wrist.

Multiaxial Movement

Movement that occurs in or around all three planes, such as in ball and socket joints like the shoulder.

Glenohumeral Joint

The ball and socket joint of the shoulder, known for its high mobility and injury risk.

Acetabulofemoral Joint (Hip Joint)

Very stable ball and socket joint of the hip with substantial ligaments to minimize dislocation.

Knee Joint

The largest and most complex synovial joint that is prone to injuries, particularly in athletes.

Temporomandibular Joint

Jaw joint that frequently faces issues due to its repeated motion and disarticulation during mouth openings.

Serrate 

Interlocking wavy lines of the Coronal, sagittal and lambdoid sutures found in the skull that help stabilize the cranial structure.

Lap(squamous)

Overlapping beveled edges of the temporal and parietal bones 

Plane(Butt)

Straight, non-overlapping edges of the palatine processes of the maxillae

Immovable joints

occur most often in either Fibrous or cartilaginous joints

Joint( Articular Capsule) 

Connective tissue that encloses the cavity and retains synovial fluid, providing lubrication and support to the joint.

General anatomy of synovial joints 

In a few synovial joints, fibrocartilage grows inward from the joint capsule

Articular disc

Forms a pad between articulating bones that crosses the entire joint capsule 

Factors influencing stability of synovial joints

Inversibility related; mobility vs stability 

Mobility of Synovial Joints

Shoulder joint; Most mobility but least stable

Stability of synovial joints

Stability outweighs mobility

Factor that plays a minor role in synovial joints stability 

Shallow surfaces less stable than ball and socket

Factor that plays a limited role in synovial joints stability

The more ligaments, the stronger the joint 

Muscle Tone

Keeps tendons taut as they cross joints(Most important)

What factor plays a active role of the central nervous system?

Muscle tone

Where is muscle tone extremely important? 

Reinforcing the shoulder and knee joints along with the arches of the foot 

What determines the Range of motion of the a joint?

structure of the articulator surfaces 

Muscle tone plays role in the muscle and tendons in what way?

state of tension maintained in resting muscles 

All muscle attach at a bone or connective tissue no fewer than how many points?

fewer than two points

Origin of synovial joints?

Attachment to an immovable end and is usually a proximal or medial attachment

Insertion of synovial joints?

Attachment to a movable end, typically distal or lateral.

Uniaxial joints 

movement in one plane an example of this is at the elbow joint involving flexion and extension 

Gliding

Not much movement

Angular

Most movement

Rotation

Rotates around a joint

A plane joint is what type of movement? 

Nonaxial movement 

What joints are mainly involved with a plane joint? 

Intercarpal joints, intertarsal joints, joints between vertebral articular surfaces 

What type of movement is a Hinge Joint?

Uniaxial movement

What joints are mainly involved with a hinge joint?

Elbow joints and interphalangeal joints 

What type of movement is a pivot joint?

uniaxial movement that allows rotation around a single axis.

What joints are involved with a pivot joint? 

Proximal radioulnar joints( Head of radius spins in place, atlantoaxial joint(C1-C2) (No joint) 

What type of movement is a Condylar joint?

biaxial movement allowing flexion, extension, adduction, and abduction.

What joints are involved with Condylar joints?

Metacarpophalangeal (knuckle) joints,{TMJ} wrist joints

What type of movement is a Saddle Joint?

Biaxial movement( only one)

What joints are involved with saddle joints?

Carpometacarpal joints of the thumb 

What type of movement is a Ball and Socket joint?

Multiaxial movement allowing rotation

What joints are involved with a Ball and socket joint?

Hip and shoulder joints

Annular ligament

Holds the Radiohead in place by wrapping around and attaching to both sides of the ulna