Hereditary multiple exostoses (HME) is a commonly inherited musculoskeletal condition and is associated with a diminished stature. We demonstrated that adults with HME were significantly shorter when compared with a control group (P<0.001); preadolescents, however, were significantly taller than predicted (P=0.01). This was reflected by their height centile; 58% of the adults were under the 25th centile, whereas 53% of the preadolescence group were above the 75th centile. Stature was more severely affected in patients with an EXT1 mutation (P=0.008). This study illustrates a novel age-related growth pattern associated with HME, which is also affected by genotype.