Injury and Healing 1 Flashcards
What types of fractures can there be?
Trauma: Low energy or high energy
Stress: Abnormal stresses on the normal bone
Pathological: Normal stresses on abnormal bone
What are the characteristics of stress fracture?
Weight bearing bones prone to activity related causes ( military )
Bone weakening = stress fracture = risk of complete fracture
- can also be increased due to disordered eating, osteoporosis, amenorrhea
What pathological fracture may occur?
Osteoporosis - soft bone
Malignancy - primary, bone mets
Vitamin D deficiency - osteomalacia/ rickets
Osteomyelitis
Osteogenesis imperfecta
Pagets
What are the characteristics of Osteopenia and Osteoporosis?
Loss of bone density
( 2.5 deviations away from normal bone density on DEXA scan)
Osteoclast activity > Osteoblast activity
Female > Male 4:1
Postmenopausal Osteoporosis ( age 50-70 )
Senile Osteoporosis - > 70
Secondary osteoporosis: Any age, 60% Male
Hypogonadism
Glucocorticoid excess
Alcoholism
Associated with ‘fragility fractures’ – hip, spine, wrist
Low energy trauma = fracture
How does Vitamin D deficiency lead to bone fractures?
Vitamin D for calcium, magnesium and phosphate absorption
less Calcium or Phosphate = Defect in osteoid matrix mineralization
Rickets in children
Osteomalacia in adults
What are the characteristics of congenital Osteogenesis imperfecta?
Brittle Bone
-autosomal dominant or recessive
Decreased Type I Collagen due to:
Decreased secretion
Production of abnormal collagen
Insufficient osteoid production
Effects: Bones, Hearing, Heart, Sight
What are the characteristics of Pagets disease?
Genetic & Acquired factors
Excessive bone break down and disorganized remodeling = deformity, pain, fracture or arthritis
May transform into a malignant disease
4 stages:
- Osteoclastic Activity
- Mixed osteoclastic-osteoblastic activity
- Osteoblastic activity
- Malignant degeneration
Examples of primary bone cancers?
Osteosarcoma
Chrondosarcoma
Ewing Sacroma
Lymphoma
Examples of Secondary bone cancers?
due to primary cancers:
Blastic ( bone forming cancers ) due to : Prostate and breast
Lytic ( Bone eating cancers) due to: kidney, thyroid, lung
How to describe fractures?
Soft tissue can be open or closed
Bony fragments can be described as greenstick, simple or multigragmentary
Movement described as displaced or undisplaced
How do fractures heal - using general tissue healing principle?
Bleeding –> Inflammation –> New tissue formation –> remodelling
( due to blood –> neutrophils, macrophages –> fibroblasts, osteoblasts, chondroblasts –> macrophages, osteoclasts’/blasts to remodel )
How to fractures heal?
Inflammation :
Haematoma formation
Release of Cytokines
Granulation tissue and. blood vessel formation
Repair : Soft Callus formation (Type II Collagen - Cartilage) Converted to hard callus (Type I Collagen - Bone
Remodelling:
Callus responds to activity, external forces, functional demands and growth
Excess bone is removed
What is the Wolff’s law?
Bone Grows and Remodels in response to the forces that are placed on it
Describe primary bone healing?
Primary Bone Healing:
Intramembranous healing
Absolute stability
Direct to woven bone
Describe Secondary bone healing?
Secondary bone healing Endochondral healing Involves responses in the periosteum and external soft tissues Relative stability Endochondral ossification: more callus
How long do the following take to heal?:
Phalanges: Metacarpals: Distal radius: Forearm: Tibia: Femur:
Phalanges: 3 weeks Metacarpals: 4-6 weeks Distal radius: 4-6 weeks Forearm: 8-10 weeks Tibia: 10 weeks Femur: 12 weeks
- 3-12 weeks depending on size, signs of visible healing on Xray from day 7-10
How are fractures managed?
Reduce: bring fracture bones together ( reduction )
Hold : Metal or no metal
Rehabilitate : Move, Physio, Use
How do we reduce fractures?
Closed reduction : ( pulling on them ) - manipulation / taction = skin or skeletal pins in bone
Open reduction: Mini incision or full exposure
How do we hold fractures?
Closed holding : plaster or traction = skin or skeletal
Fixation Holding
How do we hold fractures through fixation?
Internal fixation : Intramedullary - Pin or nails
Extramedullary- Plate/screws or pins
External fixation:
Monoplanar
Multiplanar
How do we rehabilitate fractures?
Use : Pain relief = restrain
Move
Strengthen
Weight bear
What can go wrong with a tendon?
Tendinosis : abnormal thickening
Tendinitis: Inflammation
Both can lead to rupture
How to classify ligament injuries?
Grade I – Slight incomplete tear – no notable joint instability
Grade II – Moderate / Severe Incomplete Tear – Some joint instability. One ligament may be completely torn
Grade III – complete tearing of 1 or more ligaments – Obvious instability = Surgery
- can see bruising under skin
How can we treat tendon or ligament tears?
Immobilise : plaster or boot/brace
Surgical repair : suture
What are the pros and cons of immobilisation of injured ligaments?
Pro: less ligament laxity (lengthening)
Cons :
- Leads to scar tissue
- protein degradation exceeds protein synthesis r net d in collagen quantity
- production of inferior tissue by blast cells
- resorption of bone at site of ligament insertion
- decreased tissue tensile strength (50% in 6 - 9 weeks)
What are the benefits of mobalisation of injured ligaments?
ligament scars are wider, stronger, and are more elastic
Better alignment / quality of collagen
How to Ligaments heal?
Inflammatory phase ( hours-days)
Proliferation phase , Growth factors/cytokines ( weeks to months )
Tissue remodelling, Collagenase/enzymes/macrophages/blasts ( months )
What factors can affect tissue healing?
- Mechanical environment
movement
forces
-Biological environment Blood supply Immune function Infection Nutrition.
