1. Diffusion-weighted MRI for outcome prediction in early Legg-Calvé-Perthes disease: Medium-term radiographic correlations
- Author
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Julie Vial, Gauthier Gracia, Jérôme Sales de Gauzy, Franck Accadbled, and Christiane Baunin
- Subjects
Male ,medicine.medical_specialty ,Adolescent ,Radiography ,03 medical and health sciences ,Femoral head ,0302 clinical medicine ,Predictive Value of Tests ,Medicine ,Effective diffusion coefficient ,Legg-Calve-Perthes disease ,Humans ,Orthopedics and Sports Medicine ,Prospective Studies ,Stage (cooking) ,Prospective cohort study ,Child ,Femoral neck ,030222 orthopedics ,business.industry ,Femur Neck ,Patient Selection ,030229 sport sciences ,medicine.disease ,Prognosis ,Surgery ,body regions ,medicine.anatomical_structure ,Diffusion Magnetic Resonance Imaging ,Legg-Calve-Perthes Disease ,Female ,Radiology ,business ,Diffusion MRI - Abstract
Outcome prediction at the early sclerotic stage of Legg-Calvé-Perthes disease (LCPD) is valuable to select patients likely to benefit from early surgery. The metaphyseal apparent diffusion coefficient (ADC) ratio correlated significantly with Herring's classification of LCPD in a preliminary study of 49 MRIs, in which values greater than 1.63 were associated with poor outcomes. The objective of this study was to determine whether the femoral neck ADC ratio, with the 1.63 cut-off, determined at the initial stage of LCPD correlated with medium-term radiographic outcomes.The metaphyseal ADC ratio correlates significantly with medium-term radiographic outcomes of LCPD.A prospective study was performed in 27 children (mean age, 13 years; range, 9.5-16 years) who underwent 49 MRIs at the sclerosis or fragmentation stage of unilateral LCPD. ADCs measured bilaterally at the femoral head and neck were used to compute the corresponding ADC ratios between the affected and unaffected sides. The patients received regular follow-up for at least 5 years. The correlation between the ADC ratios and Stulberg grade at last follow-up was assessed.After a mean follow-up of 6.8 years (range, 5.2-8.4 years) from the date of the first MRI, 13 hips were Stulberg 1 or 2, 13 were Stulberg 3 or 4, and 1 was Stulberg 5. The metaphyseal ADC ratio increased significantly with the Stulberg grade (p0.01). When only MRIs obtained at the early stage of sclerosis were considered, the correlation remained significant (p=0.03). It was also significant in the subgroup of surgically treated patients (p0.0001) but was not significant in the subgroup without surgery (p=0.51). A metaphyseal ADC ratio greater than 1.63 was associated with a worse Stulberg grade (p=0.02).Diffusion-weighted MRI is a non-irradiating and non-invasive investigation that contributes to the management of LCPD when used in combination with morphological MRI sequences. Elevation of the femoral neck ADC is a finding of adverse prognostic significance that correlates with Herring's grade at the fragmentation stage and with Stulberg's grade at the healed stage. Early ADC elevation in the affected femoral neck can serve to select those patients most likely to benefit from early surgery before the fragmentation stage, i.e., before Herring's classification can be applied.III, prospective uncontrolled study 3.
- Published
- 2018