UNIVERSITY OF THE PEOPLE
PUBLIC HEALTH MAJOR
HUMAN ANATOMY
UNIT CODE : HS 2211
WEEK 2: OF T1 0F AY2023
WRITTEN ASSIGNMENT UNIT 2
INSTRUCTOR: Branko JabIanovic
This assignment will discuss hinge joint of the human body, give detailed anatomical
compositions, its structure, functionality, and usage of physiological terms as applicable in
the field of anatomy and physiology.
Introduction
A joint is point in skeletal system where bones meet or where bones and cartilage or tendons
meet. Physiologically, the more a joint moves the weaker it is. Some joint exhibit firmness
and would by any fault show tendency strain. In anatomy, joints are classified by their
structure and function. Structure wise, joints may be connected by a strong fibrous joint, or
by cartilage or by synovial joints. By function, the joints determined based on their level of
mobility or movement. In this category we have bones which are immovable, partly movable.
and those that can move with ease. The immovable are called synarthrosis and those that can
slightly move are the amphiarthrosis. Generally, the two classifications have a strong fibrous
joint that are highly beneficial in protecting delicate organs of the body, and as such, are the
most stable and stronger joints of the body. The movable category are the diarthrosis which
comprises of synovial joints where the hinge joints belongs to.
Hinge joint
A hinge joint is a uniaxial joint of the upper limb forming the larger synovial joint of the
body. The bones at this joint interlock each other as shutter operates the door, allowing
movement in one plane. It's made up of two to three bones that are held in position by
ligaments and other connective tissues such as cartilage and muscles engrossed in synovial
fluid zone. It comprises of the elbow, knee, joint of the hand and foot, and the joint of the
ankle.
Hinge joint moves in one plane by allowing flexion and extension. This it does by making
either short or long moves depending on the strength of muscles contractions applied to the
other bone. By their very nature and composition, hinge joints is flexed by very strong
muscles, mechanically latched by tendons and ligaments that provides stability, power, and
flexibility. For that reason, it ranked stronger and firm joint as compared to the ball-and-
socket joint. The flexion components of the motion is an implied functions of the brachialis.
biceps and brachioradialis muscles emerging from humerus and scapula and extend the same
to ulna and radius. On the other hand, the extension motion is facilitated by the triceps brachii
and the posterior muscles (anconeus) of the humerus and the scapula (Aquilina et al., 2017).
The flexion of the knee is made possible by the coordinative functions of the articularis
genus, rectus femoris, vastus lateralis, vastus intermedius and vastus medialis. These muscles
collectively originates partly from the anterior inferior iliac of the spine and the the femur.
The trio; vastus intermedius, medialis and lateralis consolidate their support to form the
patella tendon, which crosses