Note that contracture refers to a reduction of joint mobility due to permanent shortening of the soft parts around a joint, muscles, tendons, ligaments, fasciae, or skin. Ankylosis and contracture can occur together or alone. Fibrous ankylosis refers to adhesions between the opposing surface of a joint. Cartilaginous ankylosis implies the fusion of two apposed cartilaginous surfaces. Bony ankylosis or synostosis refers to an osseous union between articulating surfaces.