Week 1 - Joints And Bones of the Upper Limb Flashcards
How do you classify joints?
According to the tissue uniting the bone
- Hence there are fibrous, cartilaginous and synovial joint
What types of tissue can be located between joints?
- Fibrous
- Cartilaginous
- Synovial
What are some characteristics of joints?
- Most are moveable, some are not
- Can be rigid or flexible, depending upon the strength and range of movement possible at a particular site
- Movement at joints is smooth and controlled
- Receive abundant blood and nerve supply
What does the stability of a joint depend on?
- The shape, size and arrangement of the articulate surfaces
- The ligaments
- The tone of the muscles around the joint
What are joints?
Articulations between 2 or more bones
Describe some characteristics of fibrous joints
- Fixed
- Immobile
Where can fibrous joints be found?
- Sutures in skull
- Teeth (gomphosis)
- Interosseous membranes (between the radius and ulna)
- Syndesmosis
Describe cartilaginous joints
Connecting medium is hyaline cartilage or fibrocartilage
Can be primary (synchondrosis) or secondary joints (symphysis)
Primary:
- Only involve hyaline cartilage
- Joints can be immovable (synarthroses) or slightly movable (amphiarthroses)
Secondary joints:
- Can involve hyaline cartilage or fibrocartilage
- Joints are slightly moveable (amphiarthroses)
- E.g. Public symphysis
- E.g. Joint between the diaphysis and epihphysis of a growing long bone
Describe synovial joints
- A joint filled with synovial fluid
- Tend to be fully moveable (amphiarthroses)
- Main type of joint found around the body
- Defined by the arrangement of their articular surfaces, and the types of movement they allow
- Many different types
- Have 3 main features: articular capsule, synovial fluid, articular cartilage
- Also has accessory structures (e.g. Menisci) and ligaments (extrinsic and intrinsic)
What types of synovial joints are there?
- Hinge: permits flexion and extension (e.g. Elbow joint)
- Saddle: concave and convex joint surfaces (e.g. Metatarsophalangeal joint)
- Ball and socket: permits movement in several axes (e.g. Shoulder and hip joints)
- Condyloid: permits flexion and extension, abduction, addiction and circumduction (e.g. Metacarpophalangeal joint)
- Pivot: allows rotation, they are round bony processes that fit into a bony ligamantous socket (e.g. Atlantoaxial joint, proximal radioulnar joint)
- Plane: permits gliding or sliding movements (e.g. Acromioclavicular joint)
What are the roles of the skeleton?
- Support
- Protection
- Shape
- Movement (attachments for muscles; levers)
- Haemopoiesis (red marrow)
- Mineral storage (bone matrix)
- Lipid storage (yellow marrow)
What is the structure of the skeleton?
There is an axial and appendicular skeleton Axial: - 80 bones - Protection and support - Consists of: skill, vertebral column, ribcage Appendicular: - 126 bones - Mobility - Consists of: upper limb and lower limb
What different bones are there?
- Long (e.g. Femur)
- Short (e.g. Wrist)
- Flat (e.g. Skull)
- Irregular (e.g. Sphenoid)
- Sesamoid (e.g. Pisiform bones in hand, patella)
What is a tuberosity?
Roughened, rounded elevation
What is a tubercle?
Smaller elevation than the tuberosity
What is a spine?
A slender projection
What is a trochanter?
Large projection of the femur
What is a condyle?
A large prominence or rounded surface
What is a crest?
A ridge
What is a sinus?
A hollow space
What is a fossa?
A depression
What is a meatus?
A tunnel/canal
What is a foramen?
A hole/opening
What is a fissure?
A cleft/narrow slit
What is a notch?
A large groove
What is an epicondyle?
A smaller prominence above a condyle
What is the structure of a long bone?
Distal –> proximal
- Head at distal articular surface
- Neck
- Shaft
- Base at proximal articular surface
What innervates the pectoralis major?
Medial and lateral pectoral nerves (C5, C6, C7)
- Derived from the brachial plexus
Where is the pec. major?
- Origin = sternum and upper costal cartilages
- Has a sternal and a costal head
- Insertion = lateral lip of the intertubercular groove of the humerus
What are the actions of the pec. major?
Can adduct and medially rotate the humerus at the shoulder
What innervates the pectoralis minor?
Medial pectoral nerve (C8, T1)
Where is the pectoralis minor?
- Origin = anterior surface of the sternal ends of ribs 3-5
- Insertion = coracoid process of the scapula
- Lies posterior to the pectorals major
What are the actions of the pectoralis minor?
Draws scapula forward and downward
What innervates the serratus anterior?
Long thoracic nerve (C5, C6, C7)
Where is the serratus anterior?
- Origin = anterior surfaces of the first 8/9 ribs
- Insertion = anterior surface of the medial border of the scapula
What are the actions of the serratus anterior?
- Abducts scapula and upwardly rotates it whilst abducting the arm
- Stabilises scapula by holding it to chest wall
What innervates the subclavius?
Subclavian nerve (C5, C6)
Where is the subclavius?
- Origin = costochondral junction of the first rib
- Insertion = inferior surface of clavicle, in the subclavian groove
What are the actions of the subclavius?
Depresses clavicle inferiorly and anteriorly
What are the bones of the upper limb?
- Shoulder girdle (scapula and clavicle)
- Arm (humerus)
- Forearm (radius and ulna)
- Hand (carpals, metacarpals and phalanges)
How does the scapula develop?
By endochondral ossification
How does the clavicle develop?
By intramembranous ossification
How does the humerus develop?
By endochondral ossification
What lies between the radius and ulna?
The interosseal membrane
What carpal bones are found in the hand?
(from thumb to little finger)
Proximal row: scaphoid, lunate, triquetrum, pisiform
Distal row: trapezium, trapezoid, capitate, hamate
(Senior lecturers take prostitutes to the Carlton hotel)
What are the names of the fingers?
(Thumb to little finger)
- Pollex
- Index
- Medius
- Anularis
- Digitus minimus
