Purpose: To evaluate the vascularisation of the femoral head in children with slipped capital femoral epiphysis (SCFE) before and after surgery with use of contrast-enhanced MRI

Methods and Materials: 20 consecutive children, 13 boys and 7 girls, aged 9–15 years, with slipped capital femoral epiphysis, were included into the study. The classification of SCFE was performed traditionally due to the patient’s history, physical examination and findings of the radiographs. There were no pre-slips, 9 children had acute, 5 children had acute-on-chronic and 6 children had chronic SCFE. The MRI-examinations were performed in a 1.5 Tesla MR-scanner with use of the body coil and all postoperative MR-examinations were carried out within 4 weeks after surgery. The examination protocol included a coronal fat-suppressed STIR-sequence, a coronal contrast-enhanced T1-weighted spin-echo sequence and a sagittal 3D-gradient-echo (FFE) sequence. Morphology, signal intensities and contrast-enhancement of the femoral head were assessed retrospectively by two experienced radiologists in consensus.

Results: Morphologic distortion of the physis, bone marrow edema in the metaphysis and epiphysis and joint effusion were the preoperative MRI-findings of slipped capital femoral epiphysis in each child. In 17 children, who underwent in situ-fixation with a single screw, and in one child, who underwent open reduction of the epiphysis, the vascularisation of the femoral head before and after surgery was normal. An avascular zone in the posterior-lateral aspect of the epiphysis was visible preoperatively in one child, which completely revascularized after open reduction and internal fixation of the epiphysis with two screws. One child with severe SCFE developed avascular necrosis of the femoral head after open reduction and corrective osteotomy through the physis.

Conclusion: MRI allows for accurate evaluation of the femoral head vascularisation before and after surgery in children with slipped capital femoral epiphysis.