Ultrasound examination of the irritable hip
Bickerstaff, D.R.; Neal, L.M.; Booth, A.J.; Brennan, P.O.; Bell, M.J.
Journal of Bone and Joint Surgery. British Volume 72(4): 549-553
1990
ISSN/ISBN: 0301-620X PMID: 2199451 Document Number: 365460
We made a prospective study of 111 children with acute hip pain to assess whether ultrasound can replace traditional radiography. An effusion was diagnosed in 71% by ultrasound but in only 15% by radiography. This effusion persisted for a mean of nine days; symptoms lasted for five days. Two patients found to have Perthes' disease had longer-lasting effusion and symptoms. Patients without an effusion had no obvious cause for their pain, so the pressure of an effusion from a transient synovitis does not account for all patients with irritable hips. Patients with an effusion persisting for over 24 days (the mean + 2 s.d. of our series) had more symptoms, a significantly larger effusion and greater limitation of movement. They may be more at risk for avascular necrosis. We found that radiographic examination influenced the immediate management of only two patients, those with Perthes' disease. We therefore propose a protocol of management for irritable hip, using ultrasonography at the first presentation of certain categories of patients. This would reduce the number of early radiographs by 75%.