Fig. 1

Examples of coronal and transverse magnetic resonance images in four adult participants with achondroplasia: two participants without spinal stenosis (to the left), and two participants with symptomatic spinal stenosis (to the right). The performance in the six-minute walk test (6MWT) and muscle fat infiltration (MFI) in the anterior compartment are provided for each of the participants. Muscle compartments are displayed in color