This is the text of Dr. Ignacio Ponseti's 1988 AAOS guest lecture reviewing his 50-year career in orthopedics. It traces transformative advances in antibiotics, endocrinology, and molecular biology, and presents Ponseti's own histopathologic research on juvenile kyphosis, Legg-Calvé-Perthes disease, and lathyrism as a model for collagen cross-linking disorders.
Three of the most important concepts in pediatric orthopedics — Scheuermann kyphosis, Legg-Calvé-Perthes disease, and collagen cross-linking disorders. Trace directly to Ponseti's bench and clinical work described here.
For Scheuermann kyphosis: the abnormality is in the cartilage matrix of the vertebral end plate, not avascular necrosis of the ring apophysis as originally proposed. Bracing during the florid stage works because the cellular defect is mechanically reversible (Hueter-Volkmann principle). Brace early; the biology supports it.
For Legg-Calvé-Perthes: Ponseti's biopsies raise the possibility that femoral head necrosis is secondary to epiphyseal cartilage matrix failure compressing nutrient vessels. The causal direction remains unsettled. Hold this as a hypothesis, not a fact.
For collagen biology: lathyrism research is why we know lysyl-oxidase is required for collagen cross-linking, and why a specific Ehlers-Danlos subtype (lysyl-oxidase deficiency) exists as a distinct entity.
This is the text of Dr. Ignacio Ponseti's 1988 AAOS guest lecture reviewing his 50-year career in orthopedics. It traces transformative advances in antibiotics, endocrinology, and molecular biology, and presents Ponseti's own histopathologic research on juvenile kyphosis, Legg-Calvé-Perthes disease, and lathyrism as a model for collagen cross-linking disorders.
Three of the most important concepts in pediatric orthopedics — Scheuermann kyphosis, Legg-Calvé-Perthes disease, and collagen cross-linking disorders. Trace directly to Ponseti's bench and clinical work described here.
For Scheuermann kyphosis: the abnormality is in the cartilage matrix of the vertebral end plate, not avascular necrosis of the ring apophysis as originally proposed. Bracing during the florid stage works because the cellular defect is mechanically reversible (Hueter-Volkmann principle). Brace early; the biology supports it.
For Legg-Calvé-Perthes: Ponseti's biopsies raise the possibility that femoral head necrosis is secondary to epiphyseal cartilage matrix failure compressing nutrient vessels. The causal direction remains unsettled. Hold this as a hypothesis, not a fact.
For collagen biology: lathyrism research is why we know lysyl-oxidase is required for collagen cross-linking, and why a specific Ehlers-Danlos subtype (lysyl-oxidase deficiency) exists as a distinct entity.