Asphericity of the femoral head-neck junction is common in cam-type
femoroacetabular impingement (FAI) and usually quantified using
the alpha angle on radiographs or MRI. The aim of this study was
to determine the natural alpha angle in a large cohort of patients
by continuous circumferential analysis with CT. CT scans of 1312 femurs of 656 patients were analyzed in this
cross-sectional study. There were 362 men and 294 women. Their mean
age was 61.2 years (18 to 93). All scans had been performed for
reasons other than hip disease. Digital circumferential analysis
allowed continuous determination of the alpha angle around the entire
head-neck junction. All statistical tests were conducted two-sided;
a p-value < 0.05 was considered statistically significant.Aims
Methods
Osteochondrosis juvenilis is caused by a dysfunction of endochondral ossification. Several epiphyses and apophyses can be affected, but osteochondrosis juvenilis of the medial malleolus has not been reported. We describe a 12-year-old boy with bilateral pes planovalgus who was affected by this condition. Conservative management was successful. The presentation, aetiology and treatment are described and the importance of including it in the differential diagnosis is discussed.
