Abstract
This paper looks at the physical findings, microbiology and haematological results of one hundred cases of septic arthritis.
The commonest joints to be involved are the knee (43 patients) and the shoulder (39 patients). The commonest organisms cultured were salmonella typhi (19 patients), salmonella enteritidis (13 patients) and staphylococcus aureus (11 patients). Most patients are anaemic (mean Hb 8.7) and underweight (mean 74% of expected weight for age). Ten patients were found to be HIV positive and two sickle cell positive.
The pathogenesis of septic arthritis in this group is discussed. It is likely that there is a widespread subclinical salmonella bacteraemia in this population as there is a high incidence of diarrhoeal disease. The reason for the high incidence of shoulder infection is not clear. It has been noticed that most children are carried on their backs by their mothers and lifted up for this by their arms. It is therefore proposed that repetitive minor trauma to the shoulder predisposes to bacterial arrest in this area and thus development of infection. It is also proposed that the low weight and body mass index is likely to be a determinant in these patients having a reduced immunity to infection.
No grading system for septic arthritis has been published therefore a new grading system is proposed.
The abstracts were prepared by Mr Simon Donell. Correspondence should be addressed to him at the Department of Orthopaedics, Norfolk & Norwich Hospital, Level 4, Centre Block, Colney Lane, Norwich NR4 7UY, United Kingdom.
