has part has part characteristic of inheres in has modifier Abnormal diaphysis morphology Diaphyseal undertubulation UMLS:C1835473 Undertubulation of diaphyses Thickening of shaft or central part of long bones Diaphyseal widening HP:0005019 Undertubulated long bones Tubulation refers to the size and shape of tubular bones. In children and adolescents, the modeling process regulates normal bone growth. Final shaft (tube) diameter depends on appositional bone growth and the equilibrium between periosteal and endosteal bone resorption and formation. Undertubulation refers to a broad, widened form of the shafts (diaphyses) of long bones. abnormal increased thickness diaphysis