wk5 Flashcards
what are osteoblasts
Produce collagen (support and strength) and proteoglycans (polysaccharide and protein substances that transport minerals): stimulate osteoclast resorptive activity
what are osteoclasts
Maintain bone matrix, Resorb bone; assist with mineral homeostasis
what are the disease processes of musculoskeletal system
- Joint disorders
- Fractures
- Osteomyelitis
- Osteoporosis
- Paget’s disease
- Rheumatoid arthritis
- Osteoarthritis
- Gout
joint disorders
- Strains and sprains
strain vs sprain
o Strain- stretching or a partial tear in a muscle or muscle and tendon unit (a complete tear is a rupture)
o Sprain- involve damage to the supporting ligaments of a joint, or the joint capsule
whats a dislocation
the loss of articulation of the joint
o Caused by displacement of the bone ends
o Usually the result of severe trauma that disrupts the ligaments holding the bones in position
o May be traumatic, congenital or pathologic
o Signs and symptoms include pain, deformity, limited movement
o Treatment usually reduction, with assistance of pain relief or anaesthesia, and x-ray
o Joint will require immobilisation for several weeks to allow injured joining tissues to heal
o May be complicated by fractures
a herniated disk
- Discs are pads that serve as “cushions” between vertebral bodies
oHarder outer layer surrounds soft inner centre
- Outer layer split or rupture, inner layer centre squeezed outwards
oCommon in L4 & L5 lower back
- Disc tissue can press on the adjacent spinal nerves
whats a fracture
- Occurs when a greater stress is placed on a bone than it can withstand
- Causes include
o Sudden injury
o Fatigue or stress fractures
o Pathologic fractures
types of fractures
o Greenstick- a bend or partial break, common in children as they have more resilient bones
o Impacted- fractured fragments are wedged together
o Compression- two bones crushed together
o Comminuted- more than two pieces of fractured bone
TX of fractures
o First aid- ABCDE then splint the fracture- prevent movement and further injury
o Reduction of the fracture
o Immobilisation- to hold in place while healing occurs
o Preservation and restoration of function of the injured part
- Nursing Interventions o ABCDE o Pain relief o Postoperative elevation of the limb o Neurovascular observations of limb- colour, warmth, movement, sensation in extremities, pulse distal to fracture, capillary refill o Check for complications- DVT, compartment syndrome o Drains o Document o Nutrition o Physiotherapy o Social
four stages of bone healing
haemotoma formation: blood at fracture site forms a clot. this is the framework of bone repair
fibrocartilaginous callus formation: fibroblasts and osteoblasts migrate to site and begin reconstruction
Ossification: 3rd to 4th week callus is replaced with mature bone, can begin WBAT
Remodelling: reabsorption of callus from marrow space and around fracture site
complications with fractures
hypovolemic shock
- DVT
- Compartment syndrome
- Fracture blisters
- Fat embolism syndrome
- Osteomyelitis
what is compartment syndrome
- Increased pressure within a confined space
- Muscles and nerves of a limb are enclosed by a firm layer of tissue called fascia (muscle compartment)
- If there is much bleeding and/or oedema, increase in the volume of the muscle compartment
o Fascia does not stretch
o Pressure will increase inside the muscle compartment
o Pressure will cause permanent damage to muscles and nerves if not relieved
Tx of compartment syndrome
- Reduce the pressure
- If limb has a tight cast or dressing- slit these as pressure may be due to this
- Elevate limb
- Prepare for surgery- fasciotomy may be necessary to relieve pressure and save the muscles and nerves
what is osteoarthritis
- Surface crack appear in the cartilage surface
- Cracks widen down to subchondral bone
o Synovial fluid forms cysts within the bone - Articular cartilage becomes eroded, exposed bone becomes polished, thickened and hardened
- Abnormal bony outgrowths occur at the joint margins – spurs
- Joint loses its resilience and its structural integrity
