Osteomyelitis

Def – osteomyelitis is a severe pyogenic infection and inflammation of bone and surrounding tissues

Etiology Bacteria Viruses Fungi and parasites Common microorganisms are S.aureus, streptococcus, hemophilus influenzae enterobacteria, salmonella Entry of organism from an open wound or hematogenous spread

Risk factors Soft tissue infections and direct bone contamination (surgery, gunshot) Chronic illness Diabetes or vascular disease Alcohol or drug abuse Immunosuppression Elderly Poorly nourished Obese patients

Classification Based on mode of entry – classified in to Exogenous osteomyelitis Endogenous or hematogenous osteomyelitis Based on the duration Acute and chronic ostoemyelitis

Exogenous osteomyelitis Onset is insidious Caused by a pathogen outside the body or by the spread of infection from adjacent soft tissues. Example – from an open fracture or a surgical procedure can also caused by human and animal bites The infection spreads from soft tissues to the bone

Hematogenous osteomyelitis Caused by blood borne pathogens originating from infectious sites within the body Example –from sinus, ear, dental, respiratory and genitourinary infections In this the infection spreads from the bone to the soft tissues and eventually break through the skin becoming draining fistula More common in children's and older adults

Pathophysiology In hematogenous osteomyelitis Organisms reach the bone through the circulatory and lymphatic systems Bacteria lodge in the small vessels of the bone Inflammation Blockage of the vessel causes thrombosis, ischemia and necrosis of bone (femur, tibia, humerus and radius are commonly affected)

Bacteria and inflammation spread within the shaft of the bone and spread throughout the haversian systems and reach the periosteum Subperiosteal abscess Segmental bone necrosis sequestrum (dead piece of bone) new bone laid down over the infected bone by osteoblasts is called as involucrum- opening in the involucrum allow infected material to escape into soft tissue

In exogenous osteomyelitis Infection begins in soft tissues, disrupting muscle and connective tissue and eventually forming abscess

Clinical features Acute osteomyelitis – less than one month in duration CM of acute osteomyelitis are both systemic and local Systemic – fever, night sweats, chills, restlessness, nausea and malaise Local – severe bone pain unrelieved by rest and worse with activity, swelling, tenderness, warmth at the site Later signs include drainage from sinus tracts to the skin and fracture site

Bone infection persists for longer than 4 weeks and also failed to respond to the initial treatment

Clenched fist osteomyelitis

Complicaitons Sepsis Pathologic fracture and non union Draining fistula Shortening of the extremity Amputation Brodie’s abscesses – isolated encapsulated pockets of microorganisms surrounded by bone matrix –capable of reinfection at any time

Diagnostic measures lab studies - elevated WBC, c-reactive protein (CRP) and erythrocyte sedimentation rate BLOOD CULTURE – to find out the organisms CT scan and radionuclide bone scan X ray ,MRI, Bone biopsy History collection Physical examination

Management Goals Complete removal of dead bone and affected soft tissue Control of infection Elimination of dead space

Surgical management Debridement surgery To remove necrotic tissue Removal of sequestrum and surrounding granulation tissue (sequestrectomy) The dead space is later filled with, antibiotic beads (polymethylmethacrylate beads with either vancomycin, tobramysin or gentamicin),tissue flaps and bone grafts Beads are usually removed after 2 to 4 weeks and reconstruction is performed

Osteomyelitis with fracture Bone graft and internal or external fixation together Ilizarov technique – helps in bone lengthening and reshaping. Papineau technique - type of open bone grafting technique in which wounds are packed with cancellous bone with no attempt at soft tissue coverage.

Medical management Antipyretics and analgesics Antibiotic therapy – penicillin, cephalosporin, clindamycin Depends on the causative organism 2 to 4 weeks IV followed by 4 weeks oral medication 3 to 6 weeks in case of orthopedic implants Hyperbaric oxygen therapy may be used

Nurisng management Maintain aseptic technique during dressing Observes for signs and symptoms of complications Timely medication – for effective action of antibiotics Complete rest for early healing Fracture prevention Use splints and other assistive devices ROM exercises to prevent contractures and functional deformities Provide diet high in vitamins and proteins

Nsg diagnosis Acute pain Activity intolerance Impaired physical mobility Risk for fracture Deficient knowledge

Relieving pain Restrict activity Immobilize affected part – use splints Handle affected part with care Elevate affected part to reduce swelling and discomfort Administer prescribed analgesic Monitor neurovascular status of affected extremity

Controlling infectious process Monitor response of treatment Observe IV sites for phlebitis or infiltration If surgery is planned, ensure adequate circulation Maintain aseptic technique Avoid pressure on grafted area Monitor general health Provide a balanced diet high in protein and vitamin C to promote healing

Home and community based care Self care Strict therapeutic regimen of antibiotics Prevention of falls Teach patient how to maintain and manage the IV access site and equipment it there Provide medical education (drug name, dose, frequency and administration) Instruct patient to observe for elevated temp, drainage, adverse reactions Teach patient and family how to perform aseptic dressing Explain the importance of follow up