Fibroblast growth factor 2 (FGF2) inhibits proliferation and hypertrophy of chondrocytes in the growth plate, synthesis of cartilage matrix, terminal differentiation of hypertrophic chondrocytes and matrix calcification. Recent studies have found that mutations in the receptor for fibroblast growth factor 3 (FGFR3) cause achondroplasia, hypochondroplasia and thanatophoric dysplasia. These mutations evoke uncontrolled stimulation of the receptor, leading to inhibition of bone growth. Inactivation of the receptor in experimental animals causes excessive chondrocyte proliferation and abnormal bone length. Chondrocyte stem cells proliferate in the ossification groove of Ranvier and contribute to both peripheral and longitudinal growth of the growth plate. They express FGFR3, have a potential to differentiate into chondrocytes and are therefore considered adequate for healing cartilage defects in the articular surface. It is at present unknown what happens to the chondrocyte precursor cells in the ossification groove of patients with FGFR3 mutation.