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Trauma & Orthopaedics Revision
BONE AND JOINT INFECTIONS - Go to Main Contents
| Acute haematogenous osteomyelitis |
| Brodie's abscess |
| Chronic osteomyelitis |
| Classification |
| Septic arthritis |
| Subacute osteomyelitis |
(1) Acute hematogenous osteomyelitis
(2) Sub acute osteomyelitis. Brodie's abscess is classified under this heading by some authors.
(3) Subacute epiphyseal osteomyelitis
(4) Chronic osteomyelitis
(5) Chronic-sclerosing osteomyelitis
(6) Osteomyelitis of miscellaneous group caused by rare organisms like salmonella, brucella, tuberculosis etc.
Blood supply of the epiphyses and metaphyses
(1) In an infant some metaphyseal vessels may penetrate the open growth plate and ramify in the epiphyses
(2) In a child - nutrient artery terminates in end artery adjacent to the growth plate
(3) In an adult metaphyseal and epiphyseal vessels communicate freely
Chronic bony infection forms sequestra, which is the dead bone. Involucrum is the new bone laid down by the periosteum, and it surrounds the sequestra. Cloacae are the openings in the outer involucrum through which the sequestra make its way out.
Laboratory and x-ray investigations as well as isotope bone scan are helpful.
Acute haematogenous osteomyelitis -
Most common pathogens:
(1) Infants less than 1 year, group B streptococcus, staphylococcus and E-coli
(2) Children 1 to 16 years - staph. aureus, streptococcus pyogenes and haemophilus influenzae
(3) Adults: staph. aureus
Subacute osteomyelitis: Brodie's abscess most common organism is staph. aureus.
Subacute epiphyseal osteomyelitis: The only causative organism is staph. aureus and typically affects the talus in children.
Chronic osteomyelitis: Most common organism is staph.aureus.
Staging is done by Ceirny as
Type I endosteal
Type II superficial
Type III medulla as well as cortex is involved
Type IV diffused involvement
Infection can occur at any age.
Most common organisms:
(1) Children under 2 years - H.influenzae and staph. aureus
(2) 2 to 16 years: staph.aureus and streptococcus pyogenes
(3) 16 to 30 years- N. gonorrhoea and staph.aureus
(4) More than 30 years - Staph.aureus and streptococci
