Osteomyelitis is an infection of the bone or bone marrow by pyogenic bacteria and fungus.Osteomyelitis indicates the infection of the bone or bone marrow which may spread to the bone cortex and periosteum through the Haversian canals.It leads to inflammatory destruction of the bone and if the periosteum is affected, necrosis.When dead bone is detached from healthy bone, it is termed a sequestrum.A large sequestrum that stays in the tissue becomes a focus for ongoing infection.An involucrum indicates viable periosteum that is separated from the underlying bone and which develops new bone around it.Osteomyelitis may be acute or chronic (becoming worse over months or even years) and can be further classified into two main subgroups:1. Hematogenous osteomyelitisThis is an infection occurring from hematological bacterial seeding from a remote infection.2. Direct (contiguous) osteomyelitisThis form of infection happens where there is direct contact of infected tissue with bone such as during a surgical procedure or after traumatic injury.Medical signs are likely to be more localized and there are often multiple organisms affected.The causes of Osteomyelitis are1. Staphylococcus aureus bacteria (80%) including strains of meticillin-resistant S. aureus (MRSA).2. Streptococci Group A & B3. Enterobacter species4. Haemophilus influenzae5. Proteus spp.6. Pseudomonas spp.7. Pneumococci8. Salmonellae9. Coagulase-negative Staphylococcus spp.10. Mycobacteria.Systemic mycotic (fungal) infections may also produce osteomyelitis.1. Blastomyces dermatitidis2. Coccidioides immitis.The most frequent site of infection is the distal femur and the proximal tibia in children and cancellous bone in adults.Eventually any bone may be involvedIn children,1. The long bones are normally involved in children.2. Spread of bacteria happens from the bloodstream from a skin boil, dental abscess, direct injury to the bone.In adults1. Injury to the bone is the most frequent cause.The bone injury is normally exposed to local infection in the skin or environmentSymptoms:1. Pain and swelling of the bone2. Fever3. ToxemiaSigns:1. Hot tender bones2. Throbbing pain of bones3. Abscess and swellingBlood cultures are compulsory and positive in 60% of casesBone cultures (or curettage where there are linked ulcers) give the gold standard for diagnosis, with a positive test in 90% of patients.MRI is the imaging method of choice for investigation of acute osteomyelitisRadiological results revealing an osteolytic center with a ring of sclerosis is diagnosticAcute infections can be treated at first with extensive surgical cleaning linked with antibiotic treatment lasting four to six weeks.Chronic infections should be managed with extensive surgical debridement, removal of any implants and antibiotic treatment lasting three to six monthsIntravenous treatment is given at first and also over any surgical period up to 2 weeks after surgery.The change to oral therapy may occur once the medical condition stabilizes, the inflammatory markers are decreasing and there are good microbiology results.It is normally proper to delay treatment until culture and sensitivity results are receivedThe standard antibiotic treatment is six weeks of parenteral antibiotic treatment.The optimal period of treatment for chronic osteomyelitis is normally 6 monthsHyperbaric oxygen therapy has helped in the treatment of refractory osteomyelitis.Immobilization of the bone affected (bed rest, plaster casts, and splints) is usefulOsteomyelitis may also require surgical debridement to remove pus and damaged bone tissues.TABLE OF CONTENTIntroductionChapter 1 Bone Infection (Osteomyelitis)Chapter 2 CausesChapter 3 SymptomsChapter 4 DiagnosisChapter 5...