THE IRRITABLE HIP

The limping or non-weight bearing child can present a difficult diagnostic dilemma. It may be possible to avoid admission of a large proportion of these patients if septic arthritis or other serious pathology can be exclude d. We have established a continuing, prospective study of all patients admitted for hip pain (with normal radiographs) to Starship Children’s’ Hospital between two and 13 years of age. Forty-two patients had a final diagnosis of transient synovitis. Only two patients during an eight month period had septic arthritis. Due to small numbers of patients with serious pathology we compared the transient synovitis group with a retrospective review of those with septic arthritis treated at Starship Hospital in the previous four years. Following comparisons of these two groups, we found that there was a greater incidence of septic arthritis in Maori and Pacific Islanders and septic arthritis tended to occur in younger children. The patients’ initial history, temperature, white cell count and ESR were sensitive in discriminating between septic arthritis and irritable hip. Once the diagnosis of “irritable hip” was made it was unlikely to be altered. We therefore would recommend that it is possible to avoid admission in a large number of these patients. We would however continue to recommend admission for those with a clear history of current illness, Maori or Pacific Islanders, children under the age of four, those with an elevated temperature, and any patient with an elevated white cell count especially neutrophil count or ESR.