A&P joints

How would you classify the knee joint based on movement?

Diathrosis

Ligaments: Question options: 1) hold a muscle and a bone together 2) hold bones together 3) are always present within a joint cavity 4) are always lined by synovial membrane

Hold bones together

The function of bursae is to: 1)increase the blood supply 2)increase range of movements 3)reduce friction 4)reinforce the joint

Reduce friction

Rotation

medial [internal rotation] if the front of the limb is towards the body and lateral [external rotation] if it is turned away

The acromioclavicular joint is prone to subluxate. By this you mean:

The joint is partially disrupted and while the bones are in contact the articulation of the bones is misaligned

movements along the vertical axis

medial rotation/lateral rotation

extension

movement that brings two ventral surfaces apart(unfolding)

Flexion

movement that brings two ventral surfaces together(folding)

Which joint allows motion in multiple planes [ flexion/extension; adduction/abduction and rotation?

multiaxial

The movement of a bone around its long axis or vertical axis is called

rotation

The primary movement permitted at pivot joints is...

rotation

Syndesmosis

seen in the inferior tibiofibular joint [distal tibiofibular joint] where the intervening fibrous tissue is the interosseus ligament. While primarily an immovable joint, it allows slight movement, such as when jumping from heights. The bones splay at the lower end to absorb the shock. The interosseus membranes between the bones of forearm and leg also form syndesmoses

Which joint allows motion in multiple planes [ flexion/extension; adduction/abduction and rotation? 1) elbow joint 2) shoulder joint 3) intercarpal joint 4) wrist joint

shoulder joint

Tendon sheaths

similar to bursae, but differ in shape. They look like sausage-shaped ballons that wrap around long tendons subjected to friction.

Eversion

sole faces outwards or laterally

Inversion

sole of the foot faces inwards or medially

movements along antero-posterior axis

abduction/adduction

types of fibrous joints

sutures, syndesmoses, gomphoses

what movements are possible at the wrist joint which is a condyloid joint?

adduction/abduction/flexion/extension

A partially movable joint is referred to as....

amphiarthrosis

Gomphosis

are the joints between the teeth and the sockets, where a peg shaped process is inserted into a socket. Again allows v slight movement during chewing

hip joint

being more weight bearing has more stability and less mobility (ball and socket)

Fibrocartilaginous discs lie between the vertebrae in the vertebral column thus helping to form an intervertebral joint. How would you classify this joint? 1) fibrous joint 2) synovial joint 3) cartilaginous joint

cartilaginous

neck of the femur

clasped by the joint capsule to facilitate the stability.

The pectoral girdle consists of:

clavicle and scapula

Circumduction

combination of sequential movements, where the limbs describes a cone and is not a separate primary movement

Cartilaginous joints:

synchondrosis(primary), symphysis(secondary)

Sutures in babies

the bones are still membranous and there are gaps in the sutures filled by membranes called fontanelles which help in the growth of the skull to accommodate the growing brain.

Pronation

the forearm is rotated so that the palm faces backward

3 main types of joints

fibrous joints (the intervening substance is fibrous tissue) cartilaginous (the intervening substance is cartilage ) synovial (the intervening substance is synovial fluid)

Bursae

flattened fibrous sacs lined w/synovial membrane, contains synovial fluid; common where things rub together they serve to reduce friction.

Movements along transverse axis

flexion/extension

A biaxial joint such as the wrist allows which of the following movements? 1)flexion and extension 2)abduction and adduction 3)gliding movements 4)flexion/extension; abduction/adduction 5) flexion/extension; abduction/adduction ; medial and lateral rotation

flexion/extension; abduction/adduction

Plantarflexion

foot is turned so that the toes point downwards, as in standing on your toes.

Dorsiflexion

foot is turned so that the toes point upwards, as in standing on your heels.

Pronation and supination are movements that take place:

forearm

Supination

forearm is rotated so that the palm faces forward

Plane synovial joints

gliding movements along no particular axis e:g intercarpal and intertarsal joints

Shoulder joint

greater mobility but less stability, which is why it has a muscle cuff surrounding it as added protection (ball and socket)

Classification based on movement

immovable (usually fibrous joints, also called synarthroses) partially movable (usually cartilaginous joints, also called amphiarthroses) freely movable (usually synovial joints, also called diarthroses)

Sutures (synarthrosis)

in the skull where fibrous tissue connects the articulating bones

Biaxial

(movement along 2 axes) -condyloid joint, allows flexion / extension and abduction /adduction e:g metacarpophalangeal joints, wrist joint. - saddle joint, where the articular surfaces are convex on section in one direction and concave in the other. The movements allowed are flexion /extension accompanied by rotation, and abduction / adduction e:g carpometacarpal joint of the thumb (some classify these as multi-axial)

Polyaxial

(movement along all three axes) - ball and socket joint, freely movable joint allowing flexion / extension, adduction / abduction, and medial rotation / lateral rotation e:g shoulder and hip joints.

Uniaxial

(movement along one axis only) - hinge joint, (movement along transverse axis) allowing flexion and extension.e:g elbow joint, interphalangeal joints - pivot joint, (movement along vertical axis) allowing rotation, medial and lateral rotation e:g radioulnar joints,atlantoaxial joint of the neck which is used when you say 'no'

Conditions affecting joints:

-Sprains- when a ligament is stretched or torn -Dislocations- bones out of alignment with no contact at all -Subluxation- partial dislocation, with partial contact between bones -Arthritis- inflammation of joints -Gout- uric acid/ urate deposits in joints, especially the joints of the big toe.

Synchondrosis: or primary cartilaginous joints

-The intervening tissue is hyaline cartilage -which ossifies and there is no joint visible when this occurs -No movement is permitted at these joints and these develop to allow skeletal growth ex: joint between the epiphysis and diaphysis, separated by the epiphyseal disc.

Symphisis or secondary cartilaginous joints

-articular surfaces are covered by hyaline cartilage -the intervening cartilage is fibrocartilage -Slight movement is permitted/joints are seen in the midline body Ex: joints between the vertebral bodies (with intervening intervertebral discs), pubic symphisis, and joints between the 3 parts of the sternum -cartilages rarely ossify.

Synovial joints:

-most joints -articulating surfaces are covered by hyaline articular cartilage, and are separated by a cavity lined by synovial membrane which produces synovial fluid -A fibrous capsule continuous with the periosteum connects the articulating bones and the synovial membrane lines the inside of this capsule, and the joint cavity except for the articular cartilage -The synovial fluid is a lubricant and sometimes the joint cavity is divided into compartments by an articular disc which increases the movements possible, such as in the knee joint

three factors determine the strength or stability of the synovial joint, and the range of movement permitted by it

1. The shape of the articular surfaces of the bones 2. The ligaments: strong bands of dense fibrous connective tissue which bind the adjacent bones together 3. Muscles which extend between the two bones comprising the joint.

An intervertebral joint has fibrocartilaginous intervertebral discs present between the two vertebrae. How would you classify this joint? 1. diarthrosis- freely movable 2. amphiarthrosis- partially moveable 3. synarthrosis- immovable

2. amphiarthrosis- partially moveable

what is a joint?

A joint is formed where two or more bones articulate with each other. They are classified based on the material intervening between the articulating surfaces

An example of a secondary cartilaginous joint is:

Joints between the vertebrae

Abduction

Movement away from the midline of the body

adduction

Movement toward the midline of the body