the next phase is the replacement of the hyaline cartilage and woven bone with lamellar bone. the replacement process is known as endochondral ossification with respect to the hyaline cartilage and bony substitution with respect to the woven bone. substitution of woven bone happens before substitution of hyaline cartilage. the lamellar bone begins forming soon after the collagen matrix of either tissue becomes mineralized at this stage, the process is induced by il-1 and tnfα. the mineralized matrix is penetrated by microvessel and numerous osteoblasts. the osteoblasts form new lamellar bone upon the recently exposed surface of the mineralized matrix. this new lamellar bone is in the form of trabecular bone. eventually, all of the woven bone and cartilage of the original fracture callus is replaced by trabecular bone, restoring most of the bone's original strength