Introduction to the musculoskeletal system Flashcards
Revision
What do axial bones consist of?
They are the bones of the skull.
The bones of the neck, including the cervical vertebrae and the hypoid bone.
The bones of the trunk (chest, abdomen and back).
(The axial skeleton essentially runs down the midline).
What are the two separate parts that the skeleton can be divided into?
The axial skeleton and the appendicular skeleton.
What bones does the appendicular skeleton consist of?
Bones of the pectoral girdle.
Bones of the upper limbs
Bones of the pelvic girdle.
Bones of the lower limbs.
What are the bones in the upper limbs?
1 long bone in the arm: the humerus
2 long bones in the forearm: radius and ulna (your thumb radiates away from your hand and the radius is on the same side as your thumb)
Hand: carpal bone (wrist)
metacarpals (palm) (meta=after metacarpals=after carpals)
phalanges (fingers)
What are the bones in the lower limbs?
1 long bone in the thigh: femur
2 long bones in the leg: tibia and fibula
foot: tarsal bones (hindfoot/midfoot)
metatarsals (forefoot) (meta=after metatarsals=after tarsals)
phalanges (forefoot-toes)
What is a bony feature?
A bony feature is something you find on bones (e.g. a groove, lump or bum) that is developed during bone growth and makes the bone functional, the best shape for the job.
What causes bony features?
Bony features are normally caused by an adjacent structure e.g. a tendon, a blood vessel, a nerve or another bone, which applies a force to the developing bone moulding it’s shape accordingly.
It can also sometimes be caused by an adjacent structure developing at the same time as the bone. The bone has to grow around the other structure forming a foramen (hole).
What are examples of bony features in the upper limb?
Greater tubercle (tuberosity) of the humerus. Styloid process of the radius (Anytime you see the word stylo you are looking for a little point, like a pen).
What is the skeleton made up of?
It is made up f a combination of bones and cartilage.
What is the definition of bone?
It is a hard connective tissue.
What are the functions of bone?
Support and protection of the body and organs
Calcium metabolism
Red blood cell formation
Attachment for skeletal muscles
What are the functions of cartilage?
It is less rigid than bone and so is located mostly but not exclusively where mobility is required, at articulations (joints).
Movement of the skeleton occurs at joints. How do the muscles allow the joints to move?
The skeletal muscles contract to move the bones.
Without joints we couldn’t move.
There are different types and subtypes of joints. What are the main 3?
Synovial (the most moveable)
Cartilaginous (the next most moveable)
Fibrous (the least moveable)
Each joint is a compromise between mobility and stability. what is the relationship between these?
Increased mobility = decreased stability
decreased mobility = increased stability
What is the name of the nerves that supply the joints and what is the result of their presence?
Joints have an excellent sensory nerve supply.
Sensory nerves detect some type of sensation.
This means that they hurt a lot when dislocated or affected by pathology e.g. arthritis.
What are the 4 sensations detected by the sensory receptors of the joint nerves?
Pain
Touch
Temperature
Proprioception (joint position sense), this can also be explained as an awareness of where your body is in space, e.g. allows you to close your eyes and touch your nose.
The arteries supplying joints arise from large named arteries located near the joint. these are called what?
Articular branches.
What type of arteries are common around the joint?
Periarticular (meaning around the joint) arterial anastomoses.
These are present in addition to the main blood supply. This helps to prevent the blood supply from being cut off.
What can happen to the arteries supplying joints, if the joint is dislocated?
The arteries supplying joints can be damaged by dislocations, dangerously compromising the blood flow to distal joints.
What are the roles of skeletal muscles?
Their primary role is to produce movement however, they also provide some structure and are involved in heat production.
Where are skeletal muscles normally found?
Deep in the deep fascia.
What is the deep fascia?
It is a tough fibrous connective tissue covering the body.
The shiny white appearance is the deep fascia
What are the layers that lead down to the skeletal muscle?
Epidermis (epithelium) is what we know as skin.
Next is the dermis made of collagen and elastic fibres.
Then is the superficial fascia (adipose tissue), this is a fatty tissue, the superficial fascia also has a bit of connective tissue.
The deep fascia is a really thick tough fibrous tissue covering the skeletal muscles. The shiny whit appearance is the deep fascia. Generally the muscles are found in the deep fascia but not always e.g. facial muscles.
What are the advantages of long muscle fibres?
They have a greater potential range of shortening.
They have a greater potential range of movement produced at a joint.