Most patients with clinically apparent juvenile osteochondritis dissecans (JOCD) are between 12 and 19 years of age. Often the disease can be treated successfully with nonoperative modalities, but even in cases where the initial lesion resolves, patients may be predisposed to osteoarthritis later in life. While repetitive microtrauma is suspected to be involved in the development of JOCD, the exact etiology remains poorly understood, even 130 years after the condition was first described.
In the December 19, 2018 issue of The Journal, Toth et al. histologically examined 59 biopsy samples from the central condyles of 26 pediatric cadavers to look for areas of epiphyseal cartilage necrosis. Hypothesizing that such evaluation would reveal some lesions similar to those found in animals, the authors did indeed identify 6 samples with 1 or more areas of necrotic cartilage, which were either incorporated into subchondral bone or associated with focal failure of endochondral ossification. Those characteristics are consistent with a similar disease process called osteochondrosis manifesta seen in pigs and horses. While the clinical significance of these findings remains to be determined, the authors suggest that they may help explain an epiphyseal etiology of JOCD, and the data suggest that these microscopic changes (some of which are rendered in this article as whole-slide images) are probably present in young people 5 to 10 years prior to the clinical manifestations of JOCD.
These findings lend credence to the theory that the underlying etiology of JOCD primarily involves the epiphyseal growth plate rather than subchondral bone. Furthermore, the similarities between these cadaveric specimens and osteochondrosis manifesta lesions in porcine and equine femoral condyles may help us develop improved models to better diagnose, prevent, and treat this pathology.
Chad A. Krueger, MD
JBJS Deputy Editor for Social Media
Each month during the coming year, OrthoBuzz will bring you a current commentary on a “classic” article from The Journal of Bone & Joint Surgery. These articles have been selected by the Editor-in-Chief and Deputy Editors of The Journal because of their long-standing significance to the orthopaedic community and the many citations they receive in the literature. Our OrthoBuzz commentators will highlight the impact that these JBJS articles have had on the practice of orthopaedics. Please feel free to join the conversation about these classics by clicking on the “Leave a Comment” button in the box to the left.
“Injuries Involving the Epiphyseal Plate” by Drs. Salter and Harris, published more than a half-century ago, has had a lasting impact on the field of orthopaedic surgery and on the practice of medicine in general. Every surgeon in our specialty—and almost every radiologist, pediatrician, and emergency physician—has at least a passing knowledge of the “Salter fractures.” This most enduring orthopaedic schema lives on in our practices because of its clarity of presentation, its guidance of our understanding, and its implications for treatment. It has outlasted many classifications developed before and since.
In addition to presenting the fracture classification in this classic and beautifully illustrated JBJS Instructional Course Lecture, the authors laid the groundwork with basic principles of mechanical failure and vascularity of the physis. The authors then use these principles to help explain how physeal damage may arise from misalignment, crushing, or vascular interruption. The authors elucidate these concepts further by presenting experimental studies of growth arrest, with resulting histology, and the effects of interpositional surgery. Salter and Harris then describe the famous five types of physeal injury and the clinical implications for treatment and prognosis.
Not content with generalities, the authors conclude with an extensive section describing the variations of physeal fractures in each long bone. The article is fun and inspiring to read because of the obvious fascination that the authors had in exploring the topic so completely. Rarely has experimental and clinical thought been so nicely interwoven. We don’t write that way now, and rarely if ever will we see a 36-page article in one of today’s orthopaedic journals; in many ways we are poorer for that.
Classification systems are highly cited and influential; they figure prominently in lists of top-cited orthopaedic articles. Those at the top earn this rank by their utility. This is just one of three monumental contributions by the late Dr. Salter of Toronto (along with introducing us to surgical reorientation of the acetabulum and to continuous passive motion). Please share your reactions to this classic article and its impact on you and your practice.
Paul Sponseller, MD
JBJS Deputy Editor for Pediatrics