ORTHO 218 Hip Fracture Flashcards
What is a fracture?
A loss of continuity of the substance of a bone due to physical force
What is a dislocation?
Complete loss of contact between articulating surfaces of a joint
What types of fractures can you get in Long bones?
Transverse, spiral, oblique, comminuted, segmental
What fractures do you get in cancellous bones?
Impacted/crush or compression
What type of fractures due you get peri-articularly?
Avulsion fractures
What are the two types of hip fracture (broadly speaking)
Intracapsular and Extra capsular
Describe an intracapsular hip fracture?
Proximal to the intertrochanteric line
Usually presents with external rotation, adduction and shortening
What is avascular necrosis and what type of hip fracture is it more likely in?
Disruption of blood supply to the femoral head more likely in an intracapsular fracture
What is the blood supply to the femoral head?
Medial and lateral femoral circumflex arteries
What is an extracapsular fracture?
Distal to the intertrochanteric line
What are the three R’s for treating a fracture?
Reduction - open/close and how accurate?
Retention - stabilise surgically or not
Rehab - Get them weight bearing asap
What type of fracture needs to be reduced very accurately - therefore surgically?
Fracture through a joint
What are the options for treating an extracapsular fracture?
Dynamic hip screw - providing optimal stability whilst still allowing micromovement
Cannulated screw can be added if additional stability is required
What are the main treatments for an intracapsular fracture?
Hemiarthroplasty or THR
What are some of the complications of fractures?
Fat embolism, nerve, vessel or visceral damage, union problems, joint stiffness or myositis ossificans
What is the 1st stage of fracture healing?
Formation of the fracture haematoma containing required cells for required regeneration - fibrin clot, polymorphs, platelets and monocytes. Later - fibroblasts, osteoprojenitor cells and vascular in growth
What is the 2nd stage of fracture healing?
Soft callous
Bony fragments become united by fibrous/cartilagenous tissue, usually when swelling and pain subside
Still possible to angulate however
What is the 3rd stage of fracture healing?
Hard callous - as the cartilage/fibrous tissue becomes mineralised and converted into endochondral and membranous bone by osteoblasts
= increased stiffness and external callous formation
What is the 4th Stage of fracture healing?
Remodelling - where woven bone becomes lamellar bone and excess callous is removed and the medullary canal reconstituted
What is osteoporosis?
Disease characteristics by low bone mass and micro architectural deterioration of bone tissue and an increased fracture risk
How do you diagnose osteoporosis?
DEXA scan
Tscore >2.5 Standard deviations from the gender matched young adult mean
How do you diagnose osteopenia?
T score between 1-2.5 Standard deviations
What is the Z score?
Bone density and number of standard deviations away from the gender and age matched mean - used more in children
What are some risk factors for the osteoarthritis?
Hypogonadism in men Smoking Alcohol Low BMI Inactivity Caucasian Medication: aromatase inhibitors and GnRH agonists
What are the treatments for osteoporosis?
Lifestyle : exercise and falls prevention
AdCalD3
Drugs:
to increase bone formation and decrease bone resorption
What drug treatment increases bone formation?
Teriparatide - recombinant human PTH given in pulses (paradoxically increases BMD!)
What drug treatments decrease bone resorption?
Bisphosphanates - alendronic acid inhibits osteoclasts
RANK ligand inhibitor - denosuman prevents osteoclast differentiation, activation and survival
What is osteomalacia(OM) and ricketts?
Inadequate mineralization of the osteoid due to vitamin D deficiency
What are some causes of OM and ricketts?
Lack of sunlight and diet deficiency/malabsorption
Medication : rifampicin and phenytoin
Liver or renal disease
Low phosphate
How do children with ricketts look?
Protruding forehead/large head
Kyphosis and pigeon chest
Protruding abdomen
Curved tibia and fibula
What are the clinical features of OM?
Bone pain
Proximal muscle weakness
Back pain
Stress fractures
What is pagets disease?
Disorder of bone metabolism
What is the pathophysiology behind pagets disease?
There is initial overactivity - excessive resorption followed by increased osteoblast activity and bone formation however new bone is woven bone (disordered not lamellar)
Where does pagets disease common affect?
Spine, pelvis, skull and femur
What can some symptoms be of pagets disease?
Often asymptomatic Bone pain - worse on weight bearing Pathological High cardiac output Compression effects - CN palsies, sciatica and cauda equina
How do you diagnose pagets disease?
Xray, increased ALP and isotope scan
How do you treat pagets disease?
Bisphosphonates - stimulate production of lamellar bone
