Osteomyelitis and Septic Arthritis in the Developing World. Aetiology.

Osteomyelitis and Septic Arthritis are usually produced by micro-organisms of which a Staphylococcus is by far the most common pathogen. However, other bacteria such as the Pneumococcus, Haemophilus, E.Coli., and Salmonella (often associated with sickle cell anaemia) can produce acute problems, and it should also be noted that certain organisms may be more prevalent in particular geographic areas. The Tubercle Bacillus and various Fungi (Madura, Actinomyces) usually result in ‘primary’ chronic disease (except in immune-suppressed patients).


Sickle Cell - SS - Disease. Note the huge heart, and infarction of the left humerus	Sickle Cell Haemoglobin C Disease - with infarction and collapse of a segment of the femoral head. This occurs in older children and young adults

Sickle Cells in a Blood Film	Multiple bone infarcts in sickle cell SS disease

Osteomyelitis and septic arthritis may result from blood borne infections such as with umbilical sepsis in the new born, or they may follow breach of the skin and local soft tissues either from within as part of a compound fracture, or from without (gunshot wounds, surgical operations) and may then be associated with the introduction of foreign material. However, more often than not there is no obvious site of origin of the infection.


Osteomyelitis in the newborn - with a probable pathological hip dislocation

Virtually every known microrganism (other than the viruses) has been found to be implicated in acute and chronic bone and joint infections, and there is always a possibility of secondary infection in the presence of a sinus. When there is associated HIV/Aids infection various ‘unusual’ organisms may be isolated on culture.

Chronic bone and joint problems may follow acute infections, or occur slowly when caused by infection with the tubercle bacillus or certain fungi.

‘Trauma’ such as a direct blow is often blamed as a cause of an acute bone infection, and this tenet is difficult to prove or to disprove as certainly in the Developing World nearly every ill or disabled child will give a history of preceding trauma, whether the diagnosis is of idiopathic knock knees, poliomyelitis, ‘deformity’ or acute/chronic osteomyelitis. Prior treatment by a traditional healer can also be blamed.

While the history is certainly of great importance this can often be grossly misleading in the Developing World (and indeed elsewhere) and a high level of suspicion often helps in establishing an accurate diagnosis.

Bone and Joint Infections can also present from other ‘often fascinating’ causes, and here are a few examples:


Part of a Guinea Worm removed from a pus filled knee joint.	Ankylosis of an old Guinea Worm Knee	A post amputation 'ring-sequestrum'.

Bilateral hip ankylosis after septic arthritis (okay for elephant riding).