Osteonecrosis of the femoral head associated with slipped capital femoral epiphysis.

Kennedy JG, Hresko MT, Kasser JR, Shrock KB, Zurakowski D, Waters PM, Millis MB. J Pediatr Orthop 2001 Mar-Apr;21(2):189-93

We performed a retrospective analysis of 212 patients (299 hips) with slipped capital femoral epiphysis (SCFE) over a 9-year period to assess the incidence of osteonecrosis of the femoral head. Risk factors for the occurrence of osteonecrosis and the influence of treatment on the development of osteonecrosis were determined. Osteonecrosis occurred in 4 hips with unstable SCFE (4/27) and did not occur in hips with stable SCFE (0/272). The proportion of hips in which osteonecrosis developed was significantly higher among the unstable hips (4/27 vs. 0/272, p < 0.0001). Among those with an unstable hip, younger age at presentation was a predictor of a poorer outcome. Magnitude of the slip, magnitude of reduction, and chronicity of the slip were not predictive of a poorer outcome in the unstable group. In situ fixation of the minimally or moderately displaced “unstable” SCFE demonstrated a favorable outcome. We have identified the hip at risk as an unstable SCFE. The classification of hips as unstable if the epiphysis is displaced from the metaphysis or if the patient is unable to walk is most useful in predicting a hip at risk for osteonecrosis.

Slipped capital femoral epiphysis: evaluation of different modes of treatment.

Rostoucher P, Bensahel H, Pennecot GF, Kaewpornsawan K, Mazda K. J Pediatr Orthop B 1996 Spring;5(2):96-101

We reviewed 91 hips with slipped capital femoral epiphysis (SCFE) after an average follow-up period of 6 years 6 months. Different treatment methods used, according to types and stages of slipping, are discussed. In situ fixation appears to be the best procedure for SCFE with < 60% displacement. Careful reduction-fixation is indicated in acute and acute-on-chronic SCFE > 60%. Primary rotation osteotomies are associated with a high percentage of complications. Secondary osteotomies should be simple (preferably a subtrochanteric derotation osteotomy) to reduce the risk of necrosis. Preventive contralateral fixation is indicated when the growth cartilage is still open.

Diagnostic imaging of the early slipped capital femoral epiphysis.

Magnano GM, Lucigrai G, De Filippi C, Castriota Scanderberg A, Pacciani E, Toma P. Radiol Med (Torino) 1998 Jan-Feb;95(1-2):16-20

INTRODUCTION: Early slipped capital femoral epiphysis (ESCFE) can be treated surgically, with excellent results, if it is diagnosed in its initial stage; however, the rate of late or missed diagnoses remains surprisingly high. PURPOSE: We compared radiography, US and MR sensitivity in ESCFE diagnosis. MATERIAL AND METHODS: We examined 21 symptomatic overweight patients (15 boys and 6 girls) aged 9 to 15 years with anteroposterior radiographs; frog leg images were not acquired in 3 cases only. US was performed in 19 cases and the images acquired with 5-7.5 MHz probes on the sagittal plane parallel to the femoral neck. MRI was performed in 9 cases, with coronal and sagittal T1 SE and T2* GE images. RESULTS: Our sensitivity rates were 66% for anteroposterior radiography (6 false negatives), 80% for combined anteroposterior and frog leg images (3 false negatives), 95% for US (1 false negative) and 88% for MRI (1 false negative). DISCUSSION AND CONCLUSION: We believe that US is the method of choice in ESCFE diagnosis; if it is negative, but pain persists, MRI should be performed.