Differentiation of Periosteal Cells in Muscle:An Experimental Study Using the Diffusion Chamber Method

Abstract

The osteo-chondrogenic capacity of the undifferentiated mesenchymal cells of the periosteum has been made use of in clinical reconstructive surgery (16, 19, 20). In the present investigation we studied the osteo-chondrogenic potency of free periosteal transplants in muscle using the diffusion chamber method. A total of 42 experimental and seven control rabbits aged four to six weeks were operated on. Periosteum was obtained from the anterior aspect of the left tibial bone by stripping. The grafts were placed in Nucleopore^® diffusion chambers with a pore size of 0.4 μm. The chambers were implanted in the anterior tibial and paraspinal muscles of the rabbit. Osteogenesis began after the second postoperative week and increased up to the 5–6 week interval when a plateau phase was reached. Chondrogenesis, which also began after the second postoperative week, reached two plateau phases; the first observed at 4–8 weeks and the second at 12–16 weeks. Neither bone nor cartilage formation could be observed outside the chambers. In the semi-open control chambers with only one end sealed, bone formed within the chamber as early as two weeks after transplantation and grew out into the adjacent connective tissue of muscle. It is noteworthy that the periosteal transplant retained its osteochondrogenic properties even when isolated in the diffusion chamber. The young age of the donor animals might have contributed to our findings.

Key Words:

• differentiation
• proliferation
• periosteum
• diffusion chamber