In an unselected series of 55 cases of slipped capital femoral epiphysis (SCFE) we observed an incidence of 25% of epiphyseal reduction, mostly unintentional. Reduction indicated physeal instability and was associated with an effusion, detected by sonography on admission, and inability to bear weight. The true prevalence of instability may be higher since an effusion was noted in 33 cases (60%) on the initial sonographic assessment. Serial radiographs showed reduction in 12 (22%), with an average change of 15.1 degrees in the head-neck angle. Serial sonography showed reduction in 7 out of 20 cases (35%), with an average change of 3.7 mm in displacement. In two cases reduction was seen on sonography but not on radiography. Of the hips which showed subsequent reduction, 12 had had a bone scan on admission; three showed initial epiphyseal avascularity but only one progressed to symptomatic avascular necrosis. All stable hips had normal epiphyseal vascularity on the initial bone scan. This indicates the importance of injury from the initial displacement in causing avascular necrosis, rather than effusion, vascular compromise or iatrogenic injury from gentle repositioning. Physeal instability in SCFE is common and should be assessed clinically on admission. It is indicated by joint effusion or inability to bear weight. A slip is very unlikely to be unstable in a child able to bear weight and with no sonographic effusion.
We used ultrasonography to study 26 hips with slipped capital femoral epiphyses. In recently slipped epiphyses the ultrasound image revealed a step at the anterior physeal outline (mean 6.4 mm), diminished distance between the anterior acetabular rim and the femoral metaphysis (mean 4.3 mm) and an effusion. As metaphyseal remodelling progressed the physeal step decreased. The femoral neck appeared straighter in hips which had been symptomatic for longer than three weeks. It was possible to measure posterior epiphyseal displacement without projectional errors and the method was accurate in diagnosing minimal slip and in staging displacement. The suggested criteria are, less than 7 mm for a mild slip, 7 to 11 mm for a moderate slip and more than 11 mm for a severe slip. We recommend ultrasonography for the diagnosis, staging and follow-up management of slipped upper femoral epiphysis.
Serial serum C-reactive protein (CRP) measurements were made, for three weeks, in 42 consecutive patients with solitary tibial fractures. The CRP response was related to the treatment: lower values were observed in 27 patients treated conservatively than in 15 operated patients. Open reduction and plating resulted in a greater response than closed intramedullary nailing. The timing of the CRP response was related to the timing of the treatment: the highest values were usually recorded two days after admission or operation. The timing of the operation did not affect the degree of CRP response. Neither the site, nor the type of fracture, nor the age of the patient played any role. Awareness of these natural CRP responses after fractures may help in the diagnosis of early post-traumatic and postoperative complications, especially infections.
A prospective study was made of 119 children with transient synovitis or any other cause for synovial effusion and elevated intra-articular pressure. During a follow-up of one year not one case of Perthes' disease was diagnosed and the late clinical and radiographic changes were minimal with moderate overgrowth of the femoral head in 33% and widening of the joint space in 14.2%. Our results do not support the widely accepted concept that Perthes' disease develops as a result of the period of elevated intra-articular pressure found in transient synovitis. Further research into this and Perthes' disease should follow the premise that they are two different diseases without any aetiological connection.
