Session 3 Flashcards
What are the functions of the skeleton?
Support, protection, movement, mineral & growth factor storage and heamatopoeisis.
List the different classifications of bones by shape
Long - eg femur Short - eg carpal Sesamoid - embedded within a tendon or muscle, eg patella Flat - eg frontal bone of cranium Irregular - eg vertebra Sutural bone - within a cranial suture
Describe the blood supply to long bones
Metaphyseal arteries enter metaphysis at the site of attachment of the capsule. Periosteal arteries supply the periosteum and 1/3 of the cortex. The nutrient artery enters the diaphysis via the nutrient foramen.
How many bones are in the vertebral column, upper limb and lower limb?
26 vertebral
64 upper limb
62 lower limb
What are the different structural classifications of joints?
Fibrous
Cartilaginous
Synovial
What are the different functional classifications of joints?
Synarthrosis - immovable
Amphiarthrosis - slightly moveable
Diarthrosis - freely moveable
What are the 3 different types of fibrous joints?
Suture - restricted to cranium. Synostosis (fusion) on completion of growth.
Syndesmosis - amphiarthrosis, two bones held together by connective tissue. Examples include inferior tibiofibular joint and radioulnar interosseous membrane.
Gomphosis - immovable joint between teeth and maxilla/mandible
What are the different types of cartilaginous joints?
Primary cartilaginous joint - hyaline cartilage, synarthrosis. Eg 1st sternocostal joint, ephyseal growth plates
Secondary cartilaginous joint - fibrocartilage, amphiarthrosis. Eg intervertebral disc, pubic symphysis
What are the characteristics of a synovial joint?
Articular hyaline cartilage (sternoclavicular, acromioclavicular, temporomandibular joints are fibrocartilage).
Fibrous capsule completely enclosing joint with longitudinal and interlacing collagen bundles - stabilises joint.
Thin, highly vascularised synovial membrane that lines the capsule and covers exposed osseous surfaces, tendon sheaths and bursa. Does not cover articular cartilage. Produces synovial fluid.
Clear synovial fluid composed of hyaluronic acid, lubricin,proteinase and collagenase. It reduces friction, absorbs shock and transports nutrients and waste.
What are bursae and tendon sheaths?
A bursa is a sac filled with synovial fluid. They can be communicating for non-communicating with the joint cavity.
A tendon sheath is an elongated bursa wrapped around a tendon.
Describe the blood supply over synovial joints
Periarticular arterial plexus. Articular cartilage is avascular. Fibrous cartilage and ligaments have poor blood supply. Synovial membrane has rich blood supply.
What is Hilton’s law?
The nerves supplying the joint capsule also supply the muscles moving the joint and the skin overlying the insertions of these muscles.
What are the different types of synovial joint? & examples
Pivot - uniaxial, eg proximal radioulnar joint and atlantoaxial joint
Hinge - uniaxial
Saddle - biaxial joint, one bone is concavoconvex, eg 1st carpometacarpal joint
Planar - flat articulating surface, sliding movements, no axis of movement. Eg sternoclavicular, acromioclavicular, intercarpal and vertebral facet joints.
Condyloid - biaxial joint, oval shaped condyle of one bone rests on the elliptical cavity of another. Eg metacarpophalangeal, radiocarpal joints
Ball and socket
What are the effects of ageing on joints?
Decreased production of synovial fluid. Thinning of articular cartilage. Shortening of ligaments and decreased flexibility.
What are the signs and symptoms of arthritis?
Pain, swelling, stiffness, redness
What is rheumatoid arthritis?
An auto immune disorder where antibodies attack the synovium. Women more commonly affected. Joint erosion and deformity - MCP and PIP joints of hands, cervical spine, feet, can involve large joints.
Describe the articulation of the glenohumeral joint
The large round humeral head articulates with the shallow glenoid cavity of the scapula, which is deepened by the glenoid labrum.
What factors contribute to the stability of the shoulder joint?
Rotator cuff muscles - their resting tone acts to pull the humeral head into the glenoid cavity.
Glenoid labrum - a fibrocartilaginous ridge surrounding and deepening the glenoid cavity.
Ligaments
Lesser extent - deltoid, long head of triceps and long head of biceps
Where does the glenohumeral joint capsule attach?
Glenoid labrum to anatomical neck of humerus