An Update on the Pathogenesis of Osteochondrosis.
Authors: Olstad K, Ekman S, Carlson C S
Journal: Veterinary pathology
Summary
# Editorial Summary: An Update on the Pathogenesis of Osteochondrosis Osteochondrosis represents a focal failure of endochondral ossification in growth cartilage, and when the overlying cartilage fractures, fragments enter the joint as osteochondrosis dissecans (OCD)—a clinically significant complication in horses and pigs. Olstad and colleagues reviewed current understanding of the underlying mechanism: ischaemic chondronecrosis resulting from disrupted blood supply to the epiphyseal growth plate, confirmed through longitudinal imaging studies using contrast-enhanced CT and T1ρ MRI alongside histological examination. The research demonstrates that whilst some lesions resolve spontaneously through bone infill from new ossification centres and phagocytosis of granulation tissue, others progress to clinically manifested disease; notably, vascular failure appears linked to the normal process of vessel incorporation into the advancing ossification front, with bacteraemia also implicated as a potential trigger for vascular occlusion. For equine practitioners, this clarifies why osteochondrosis develops during the growth phase and suggests that management strategies should consider vascular health and infection control, though practitioners should recognise that identifying the specific cause of vascular compromise in individual cases remains challenging. The field's next frontier involves distinguishing between different causative mechanisms of vascular failure and elucidating the genetic factors predisposing certain horses to osteochondrosis—information that could eventually inform selective breeding decisions and targeted preventative interventions.
Read the full abstract on PubMed
Practical Takeaways
- •Understanding that OCD stems from vascular compromise during growth helps explain why some young horses develop lesions—vascular insufficiency is the fundamental issue, not just trauma or biomechanics alone.
- •Not all osteochondrosis lesions progress to clinical disease; some resolve spontaneously, so imaging findings must be correlated with clinical signs before deciding on intervention.
- •Future management strategies should focus on identifying and modifying risk factors related to vascular development and heritable predisposition rather than only treating symptomatic lesions after they form.
Key Findings
- •Osteochondrosis results from vascular failure to epiphyseal growth cartilage leading to ischemic chondronecrosis, confirmed in pigs and horses.
- •Early lesions (osteochondrosis latens) are detectable via contrast-enhanced CT or T1ρ MRI, while chronic lesions (osteochondrosis manifesta) can be followed longitudinally using plain CT.
- •Some osteochondrosis lesions undergo spontaneous resolution through filling with bone from separate ossification centers and phagocytosis of granulation tissue.
- •Vascular failure is associated with incorporation of blood vessels into the advancing ossification front during growth, and bacteremia can cause vascular occlusion.