Osteomyelitis Flashcards
What is the definition of osteomyelitis?
Acute inflammation of the bone caused by a bacterial infection.
Where does osteomyelitis commonly occur in children?
- arms, legs, hips, shoulders, wrists
Where does osteomyelitis commonly occur in adults?
- spine, feet, pelvis
What are the most common causes of osteomyelitis?
- blood borne infection secondary to respiratory/renal/UTI
- cellulitis
- open wound over a bone
What are the predisposing factors for osteomyelitis?
- PVD
- Peripheral Neuropathy
- Diabetes
- Open #
- Surgery/injection
- Orthopaedic/dental
- Immuno-suppressed
What are the signs and symptoms of osteomyelitis?
- fever/irritability/fatigue
- nausea
- tenderness/swelling
- loss of ROM if near a joint
Treatment for osteomyelitis is based on…
- causative agent/bacteria
- route by which infection reached the bone
- duration of infection
- local and systemic factors
What is the pathogenesis of osteomyelitis?
Bacteria hides in osteoblasts - secretes pus - spreads to vascular channels - impairs blood flow - acute becomes chronic infection - ischaemic necrosis of bone (no living osteocytes)
What are the types of osteomyelitis?
- Acute hematogenous
- Secondary osteomyelitis
- Sub-acute
- Chronic development
What is acute hematogenous osteomyelitis?
- infection arises in blood
- predominantly in children
- commonly in metaphysis of long bones
- commonly in the spine in adults and in IV drug users
- usually history of blunt trauma that has created a haematoma
What are the symptoms of acute hematogenous osteomyelitis?
- fever
- chills
- localized pain/tenderness
- decreased ROM/ability to WB
- erythema
What is secondary contiguous osteomyelitis?
- secondary to contiguous infection
- common in adults
- usually secondary to an open wound
- other causes include bites, open #, surgical procedures or foreign bodies
- diagnosis not usually made until chronic infection present and sinus present
Risk of chronic osteomyelitis is increased in those with…
- PVD
- Diabetes
- decreased neurovasc status
- infection
- poor healing due to poor tissue perfusion
- frequent trauma due to neuropathy
How is osteomyelitis diagnosed?
- PROBE TO BONE
- clinical findings (subjective and objective)
- lab tests
- x-rays, MRI and CT
- histopathologic and microbiologic assessment (GOLD STANDARD)
What is chronic suppurative osteomyelitis?
- a complication of chronic osteomyelitis
- the necrotic bone forms a sequestrum of dead bone that spurs on the infection
- multiple sinuses can occur
Is acute hematogenous osteomyelitis polymicrobial?
No, it is usually infected by a single organism. Most common is staph aureus. Secondary contiguous infection is more likely to be polymicrobial.
Treatment of osteomyelitis involves…
- antimicrobial management (oral or IV antibiotics)
- surgical debridement
- drainage of pus
- stabilization of bone
- amputation
- chronic wound management
What type of benign bone tumours are there?
- osteochondroma
- osteoblastoma
- osteoid osteoma
- giant cell tumour
Describe osteochondroma.
- contains cartilage and bone
- common to growth plates of long bones
Describe osteoblastoma.
- solitary bone neoplasm
- common to vertebrae of children and young adults
- short and flat bones are most affected
Describe osteoid osteoma.
- benign osteoblastic tumour of unknown aetiology
- most often in long bones
Describe giant cell tumour.
- most common of benign tumours
What is the treatment for benign bone tumours?
- surgery
- monitor
What is a primary malignant lesion?
- originated in bone
- bone cells that become cancerous then spread through the bloodstream to other sites
What is a secondary malignant lesion?
- cancerous cells from another site (e.g. breast) spread through the bloodstream and infiltrate the bone
Describe osteosarcoma.
- most common type of primary malignant bone tumours
- usually in metaphysical regions of long bones
- penetrates and destroys bone cortex and extend to surrounding tissue
What are the symptoms of osteosarcoma?
- frequent pain in areas
- swelling
- decreased ROM
Describe Ewing’s Sarcoma.
- primary malignant bone tumour
- common in teenagers
- common in pelvis, hips, femur or tibia
- can sometimes see in soft tissue
Describe chondrosarcoma.
- primary malignant bone tumour
- relatively rare
- cancer of the cartilage cells
- common in pelvis, femur, humorous and ribs
- adults over 40
Describe multiple myeloma.
- a plasma cell tumour that can interfere with the production of blood cells
- plasma cell proliferation causes skeletal destruction
- plasmacytomas (accumulate in bone or soft tissue)
- easily misdiagnosed as back pain in early stages
What are the symptoms of multiple myeloma?
- bone pain
- persistant infection
- anaemia
- renal impairment
- back pain/pathological #
- symptoms of spinal cord or nerve root compression
What is the treatment and prognosis of multiple myeloma?
- no cure just symptoms control
- survival is 1-10 years with a average of 3 years
What is osteoporosis?
Insufficient bone formation or excessive bone reabsorption. Bone becomes brittle and fragile. Bone loses minerals faster than it can replace.
What is osteomalacia?
- impairment of bone mineralization usually due to vitamin D
- due to reduced sunlight or digestive kidney disease
- bone reabsorption is faster than bone reformation
What is Paget’s Disease?
- accelerated skeletal remodelling
- generally affects long bones and leads to enlarged bones and makes them spongy
- unknown aetiology
What are the symptoms of Paget’s Disease?
- pain
- bone deformity
- #
- arthritis
How is Paget’s Disease diagnosed?
- x-ray
- alkaline phosphatase test
What is osteochondritis dissecans?
- affects adolescents and young adults, commonly males
- spontaneous loss of blood supply to bone and adjacent cartilage
- symptoms include joint pain and loss of ROM
- treated with surgical removal
What is osteogenesis imperfecta?
- genetic disorder - mutation of COL1A1 and COL1A2 gene
- increased bone fragility, low bone mass, connective tissue problems
- associated with blue sclera, hearing loss, hyper laxity of ligaments, spinal curvature, triangular face, muscle weakness
What is the treatment of osteogenesis imperfecta?
- physiotherapy
- surgery
- braces
- orthoses
