Flashcards in Bones/Joints Deck (38):
Give an example of each classification of bones?
Long (femur), short (carpal), sesamoid (patella), irregular (vertebrae), flat (cranial bones), sutural (within a cranial suture)
Features of short bones?
Equal in length and width, have a layer of periosteum covering a v thin layer of compact bone but are mainly spongy/cancellous. Spongy bone has bone marrow between trabeculae.
What are the three areas of a long bone?
Epiphyses (proximal and distal), metaphyses, diapyses
What are the functions of bone?
Support, protection, movement (eg attachment of muscles), mineral storage, haematopoeisis
Where does haematopoeisis occur in children? Where in adults?
Children- long bones. Adults- pelvis, cranium, sternum, vertebrae
Characteristics of seesamoid bones?
Developed in tendons/muscles, they are mostly bone but consist of some fibrous tissue and cartilage too. Can be part of a synovial joint ensheathed in a Fibrous capsule.
What is the function of sesamoid bones?
Resist friction and compression of joint, enhancce joint movement, assist local circulation.
What is avascular necrosis?
Death of bone tissue, due to loss of arterial blood supply. Also called osteonecrosis, aseptic necrosis, ischaemic necrosis.
What is a joint?
An articulation between two or more bones
How can joints be classified?
Structurally and functionally.
What are the structural classifications of joints?
Fibrous, synovial, cartilaginous
What are the functional classfications of joints?
Synarthrosis (immovable), amphiarthrosis (slightly movable), diarthrosis (freely movable)
What does synarthrosis mean?
Immovable (regarding a joint)
What does amphiarthrosis mean?
Slightly movable (regarding a joint)
What does diarthrosis mean?
Freely movable (regarding a joint)
When can avascular necrosis happen?
After fracture, excessive steroid use, the bends, dislocation compressing artery.
Characteristics of fibrous joints?
Bones joined by fibres/fibrous tissue. Movement/flexibilty depends on length of the fibres, ie longer fibres=more flexible
Examples of fibrous joints?
Suture, syndesmosis (eg radioulnar interosseous membrane), gomphosis (fibres join tooth to mandible/maxilla)
what are the two types of cartilaginous joints?
What is the difference between the two types of cartilaginous joints? And name them.
Synchondrosis (primary joint)- two surfaces united by hyaline cartilage TF synarthrosis. Symphysis (secondary joint)- articulating surfaces covered in hyaline with pad of fibrocartilage between TF amphiarthrosis
Example of secondary cartilaginous joint?
Pubic symphysis, intervertebral disc, manubriosternal joint
Example of primary cartilaginous joint?
(Synchondrosis) epiphyseal plate, 1st sternocostal joint, Xiphisternal joint
What flexibility does a synovial joint have?
What is the most common type of joint?
What makes up a synovial joint?
Articulating surface covered in hyaline cartilage, outer fibrous membrane, surrounding synovial membrane. (Synovial membrane doesnt cover articulating surface). Cavity filled with synovial fluid.
What is the fibrous capsule of a synovial joint? What is its function?
Made up of collagen ligaments, with poor blood supply, permits movement but prevents dislocation.
What is the synovial membrane and what does it do?
Thin, highly vascularised, produces synovial fluid.
What is synovial fluid? What does it do?
Hyaluronic acid, lubricin, proteinase, collagenase. Reduces friction, shock absorption, nutrient/waste transport.
What is Hilton's Law?
The nerves supplying the joint capsule also supply the muscle moving it and the skin covering it too.
What are the different types of joints, movement wise?
Planar, hinge, pivot, condyloid/ellipsoidal, saddle, ball and socket
What movement can occur with a planar joint? Give an example
Gliding, sliding. Sternoclavicular, acromioclavicular
What movement can be done with a hinge joint? Give an example
Flexion, extension. Knee, ankle, humeroulnar joint of elbow.
What movement can be done with a pivot joint? Give an example
Rotation, eg pronation, supination. Proximal radioulnar joint
What movement can be done with a ball and socket joint? Give an example
(Poly/multi-axial) Flexion, extension, ABduction, ADduction, (TF circumduction), rotation. Hip, shoulder.
What movement can be done with a saddle joint? Give an example
Biaxial- Flexion, extension, ABduction, ADduction. 1st carpometacarpal joint
What movement can be done with a condyloid/ellipsoidal joint? Give an example
Biaxial- flexion, extension, ABduction, ADduction, (circumduction). Radiocarpal joint (wrist), metacarpophalangeal joints.
List some factors which affect the stability of a joint
Structure of articulating bones, use/disuse, tone and arrangement of muscles, strength and tension of joint ligaments, some hormones eg Relaxin.