The Growing Skeleton

Growth and maturation occur in a predictable pattern throughout the body and within each individual bone. In the appendicular skeleton and in the spine, endochondral ossification predominates at cartilaginous growth plates, which are sites of relative weakness in the immature skeleton and prone to injury from acute insult and overuse. This chapter will first review the normal histo-anatomy and physiology of the growth plate complex, highlighting the unique contribution of each component and shared similarities between primary and secondary complexes. Components of the growth plate complex include the physis proper, subjacent vascularity within the growth cartilage and the ossification front. This is followed by a section on imaging considerations and common imaging findings encountered with normal and abnormal growth. Finally, the Salter–Harris classification for acute fractures and examples of characteristic overuse injury patterns involving the epiphyseal, apophyseal, and secondary growth plate complexes as well as the spine are reviewed. The goal of this chapter is to provide a foundation and basic framework to better understand and anticipate potential complications and growth disturbance, and to ensure optimal follow-up and early intervention when treatment can be less invasive.