Osteomyelitis is a pus forming infection of the bone.
It is among the commonest conditions in children, decreasing as the child grows, and it increases in patients who are immune compromised, mainly aﬀecting older children.
Children develop infection in a long bone metaphysis. The commonest causative organism is Staphylococcus aureus, following infection elsewhere in the body despite the infrequency of staphylococcal
bacteremia, presumably because of that organism’s particular ability to infect bone
Most common organism
Newborns (less than 4 months
S. aureus ,Enterobacter species & group A&B streptococcus species.
Children (aged 4months to 4yrs )
S. aureus, group A streptococcus species, haemophilus influenza and enterobacter species.
Children 4yrs to adult
S. aureus (80%), groupA streptococcus species, H influenza and enterobacter species
S. aureus and occasionally Enterobacter or streptococcus species
Sickle cell anemia patients
Salmonella species are the most common in patients with sickle cell disease
- In children the long bone are usually affected. in adults, the vertebrae and the pelvis are most commonly affected.
- Acute osteomyelitis invariably occurs in children because of rich blood supply to the growing bones.
- When adults are affected it may be because of compromised host resistance due to debilitation, intravenous drug abuse, infectious root canaled teeth or other disease like immunosuppressive.
Wald Vogel Classification of Osteomyelitis
Osteomyelitis can be classified according to;
- Duration of Infection
- Mechanism of bone infection
Duration of Infection
- Acute osteomyelitis ( suppurative osteomyelitis) is usually regarded as that which occurs before there is actual bone death. Initial episodes of Edema, formation of pus, vascular congestion, thrombosis of small vessels, e.t.c
- Chronic osteomyelitis (suppurative osteomyelitis phase ) osteomyelitis involves infection both, within and around, the bone that has died. Recurrence of acute cases, Large areas of ischemia, necrosis, and bone sequestra.
N.B.: Acute osteomyelitis can lead to chronic osteomyelitis because without treatment, the infection and inflammation block the blood vessels and causes the bone to die. Chronic osteomyelitis is harder to treat Sequestra= a fragment of dead bone attached to healthy bone
Mechanism of Bone Infection
- Hematogenous: Secondary to bacterial transport through the blood. Majority of infections in children
- Associated with vascular insufficiency: Infections in patients with diabetes affecting the feet, or peripheral vascular insufficiency
- Contiguous: Bacterial inoculation from an adjacent focus. E.g. Posttraumatic Osteomyelitis like from neighboring tissue, infections from prosthetic devices
Pathophysiology of Osteomyelitis
- Causative bacteria enters bone causing an infection. Bacteria can enter bone via bloodstream, from a nearby infection, or direct contamination Risk factors include: Open wound over a bone, Open fracture, Recent surgery, Injection around bone, Medications that weaken immune system, Pre-morbid conditions (diabetes).
- In general, microorganism may infect the bone through one or more of the three basic methods.
- Via the blood stream. (haematogeneously) the most common method. From nearby areas of infection (as in cellulitis )
- Penetrating trauma including Iatrogenic causes such as joint replacement or internal fixation of fractures or secondary peripheral periodontitis in teeth
- The area usually affected when the infection is contracted through the blood stream is the metaphysis of the bone. Once the bone is infected, leukocytes enter the infected area and in their attempt to engulf the infectious organisms, release enzymes that lyse the bone.
- Pus spreads into the bone’s blood vessels, impairing their flow and areas of devitalized infected bone known as sequestra, form basis of chronic infection. Often the body will try to create new bone around the area of necrosis. The resulting new bone is often called an involucium.
- On histologic examination these areas of necrotic bone are the basis for distinguishing between acute osteomyelitis and chronic OM
- The history is usually short, 48 hours or less. Initially, there is bone pain and marked tenderness without visible inflammation. When infection spreads sub periosteally, local and systemic signs of infection appear. Pus then forms in bone and soft tissues. The appearance of the bone does not change for 10–14 days so radiographs are a baseline for future change and to exclude differential diagnoses (Ewing’s sarcoma, leukaemia). Softening of soft-tissue planes may be seen. OM is all infective process of bone (osseous) component including the bone marrow. When it is chronic, it can lead to bone sclerosis and deformity.
- Pyomyositis (bacterial infection of muscle)
- Sickle-cell disease (thrombotic crisis)(causative agent mostly S.Aureus, Salmonella also common)
- Intravenous drug use
- Prior removal of spleen
- Immune suppression
- Autoimmune disorder
- Systemic infections
Signs and Symptoms of Osteomyelitis.
- Onset is usually over several days
- Fever, usually high but may be absent, especially in neonates
- Pain (usually severe) in the affected limb
- Tenderness and increased “heat” at the site of infection, swelling of the surrounding tissues and joint
- Reduced or complete loss of use of the aected limb
- The patient is usually a child of 4 years or above with reduced immunity, but adults may also be afected.
- History of injury may be given, and may be misleading, especially if there is no fever
- Redness of the limb
- Edema of the limb
- May present with pain, erythema, or swelling, sometimes in association with a draining sinus tract
- Deep or extensive ulcers that fail to heal after several weeks of appropriate ulcer care (e.g. in diabetic foot), and non-healing fractures, should raise suspicion of chronic osteomyelitis
- Infection of joints
- Injury (trauma) to a limb, fracture (children)
- Bone cancer (osteosarcoma, around the knee) and adults.
Management of Osteomyelitis
Management can be medical or surgical or both.
Aims of management
- To preserve limb and joint function
- To prevent further complications
- Child is admitted to pediatric ward.
- Patient’s history is taken of including name, sex, address, nationality. Past medical history, past surgical history are taken
- Vital observation T,P,R and BP and recorded in patients chart
- Assessment of patient limb for redness, hotness, edema, general examination of the patient from head to toe
- Doctor is informed who will order the following investigations.
Investigations / Diagnosis
- Diagnosis is through physical examination, laboratory findings and radiological findings.
- ¾ X-ray shows
- – Nothing abnormal in first 1-2 weeks
– Loss of bone density (rarefaction) at about 2 weeks
– May show a thin “white” line on the surface of the infected part of the bone (periosteal reaction)
– Later, may show a piece of dead bone (sequestrum)
- ¾ Blood: CBC, ESR, C&S: Type of bacterium may be detected
- Immobilize the limb, splint
- Elevate the affected limb
- Provide pain and fever relief with paracetamol, or ibuprofen
- Typically patient need antibiotic for several weeks to properly treat the infections.
- Drain the infected site.
- Immobilize or stabilize the bone if necessary.
- Administer intravenous antibiotics like Cloxacillin Child: below 12yrs 50 mg/kg every 6 hours; Above 12year 500 mg IV every 6 hours for 2 weeks. Then Continue orally for at least 4 weeks (but up to 3 months) if it fails; then,
- Ceftriaxone 50mg-100mg/kg for about 10 days, vancomycin, penicillin and ciprofloxacin can also be used depending on results from culture and sensitivity.
- Administer analgesics depending on severity like, ibuprofen acetaminophen, morphine for pain relief.
- Failure to improve after 48-72 hours of antimicrobial therapy surgical intervention is considered by;
- Surgical intervention may be indicated in the following cases: Drainage of subperiosteal , soft tissue abscesses, and intramedullary purulence
- Removal of necrotic bone tissue and local pus or drainage is often necessary to speed up healing.
- – Debridement of contiguous foci of infection (which also require antimicrobial therapy)
– Excision of sequestra (i.e. weak and lifeless bone) Debridement of the area to remove necrotic tissue.
- Failure to improve after 48-72 hours of antimicrobial therapy
Surgery and antibiotics
- Continue with the Administration of intravenous antibiotics like ceftriaxone 50mg-100mg/kg for about 10 days, vancomycin, penicillin and ciprofloxacin can also be used depending on results from culture and sensitivity
- Ineffective Tissue Perfusion Related to: Inflammatory reaction, Thrombosis of vessels, Tissue destruction, Edema, Abscess formation As evidenced by: Bone necrosis, Continuation of the infectious process, Delayed healing, Pain, Erythema, Swelling, Altered sensation in the affected area, Weak peripheral pulses.
Ineffective Tissue Perfusion Interventions:
1. Establish blood flow at the site.
Blood circulation distributes nutrients throughout the body, aids in controlling waste production, enhances site recovery, and speeds up the healing process. Healthy blood flow across vessels, arteries, veins, and capillaries maximizes perfusion.
2. Manage chronic conditions and lifestyle factors.
Diabetes, peripheral vascular disease, sickle cell disease, neuropathy, smoking, malnutrition, and more affect the revascularization of the affected area. These need to be addressed before surgical intervention.
3. Provide DVT prophylaxis.
Anticoagulants should be administered as ordered to promote circulation and prevent the development of blood clots.
4. Prepare for possible surgery.
Depending on the degree of vascular insufficiency, procedures to restore adequate blood flow, such as debridement or vascular surgery may be necessary.
5. Prevention through pressure ulcer prophylaxis.
Patients who are immobile or bed-bound are at an increased risk of experiencing osteomyelitis due to pressure ulcers. By implementing appropriate interventions such as turning schedules and skin care, this can be prevented.
2. Hyperthermia Related to: Increased metabolic rate, Infection, Inflammatory response, Trauma As evidenced by: Increased body temperature, Warmth to touch, Flushed skin, Tachypnea, Tachycardia
1. Provide a tepid sponge bath.
Tepid sponge baths lower body temperature and provide comfort to the patient.
2. Apply a cooling blanket.
A cooling blanket can lower the internal body temperature by surface cooling. Monitor closely to prevent a rapid drop in body temp.
3. Initiate antibiotics.
Long-term antibiotics are required for the treatment of osteomyelitis to control the infectious process. Instruct patients that antibiotic therapy may be required for weeks.
4. Instruct on symptoms.
Teach the patient and family that if fever, chills, warmth to the skin, or skin flushing is observed that the body is attempting to fight off infection and to seek immediate assistance.
3. Acute pain Related to: Inflammation, Tissue necrosis As evidenced by: Verbalization of pain, Tenderness with palpation, Guarding behaviors, Facial grimacing, Increased vital signs.
Acute Pain Intervention
1. Reposition as needed.
Repositioning and turning can decrease the stimulation of the pain and pressure receptors.
2. Administer pain medication as prescribed.
Mild or moderate pain may be controlled with non-steroidal anti-inflammatory drugs (NSAIDs). More severe pain or pain related to debridement or surgical intervention may require oral or IV opioid medications.
3. Elevate or immobilize the site.
Elevation or splinting of an extremity may improve pain by increasing circulation.
4. Collaborate with physical and occupational therapists.
Physical and occupational therapists assist in pain management through exercise, stretching, and other techniques.
5. Anticipate referral to a pain specialist.
Osteomyelitis and its treatment can be very painful and prolonged. Acute pain can turn into chronic pain depending on the severity and pain tolerance of the patient, which may need a referral to a pain specialist.
- Cancer of the bone.