Every organ in the body can be get infected, so is Bone. Microorganisms harbouring in the bone and causing their harmful effects either by release of Toxins or eating away the bone cause local and systemic or whole body effects, this is collectively called Bone infection or Osteomyelitis.

Bone can get infected in 2 ways-
Indirect- Most common way of bone infection. Bacteria(mostly) or Fungus(very less) affecting other body parts can enter blood stream and reach the bone and intiate an infection in bone.
Direct- when we sustain injuries due to minor cuts, accidents and there is a skin cut deep enough to expose the bone the microorganisms gain access to the bone and form infection.

History- Injury with a sharp object, cuts, recent lung infection or septicemia
Sympyoms- Pain in the affected bone, inability to move it-pseudoparalysis, Fever, swelling
Signs- the affected bone is warm to touch, tender and restricted movements in the nearest joints.

Clinical examination
X ray of the affected bone to rule out any fracture( fracture can also occur in infected bone, that is called as pathological fracture)
Blood tests to check for inflammatory markers
May need MRI at times to confirm in subclinical cases.

Early detection is the key. High index of suspicion on part of the clinician will help in early diagnosis and treatment.
Antibiotics ( Intravenous for 2 weeks followed by tablet for for 4 weeks)
Certain cases where we see no or poor response to antibiotic will need further imaging like MRI or PET CT to check for any dead bone (Sequestrum, Involucrum)which act as a bed of infection.
These cases need surgery for removal of the dead bone, tissue for culture sensitivity and clearing of any visible infection in the form of pus followed by organism sensitive IV Antibiotics for 2 weeks and 4 weeks oral antibiotics.

Patients diagnosed early and responding to Antibiotics get well with little or no complications
Delay in diagnosis can lead to myriad of complications like Fracture, repeated surgeries, limb shortening, joint stiffness at times more severe SEPSIS with Multi organ failure can also develop.