What are the most common locations for OCD lesions in dogs and horses?

What are the most common locations for OCD lesions in dogs and horses?

• A. Dogs stifle joint; horses shoulder joint.
• B. Dogs hip joint; horses elbow joint.
• C. Dogs scapulohumeral joint; horses femorotibial or tibiotarsal joints.
• D. Dogs carpal joints; horses carpal joints.

Answer: (C)

Osteochondrosis dissecans lesions develop in young animals where abnormal endochondral ossification creates focal cartilage defects in weight-bearing joints, with the typical sites differing by species due to how they move and load their joints. In dogs, the shoulder joint (scapulohumeral joint) is a commonly affected location, where cartilage irregularities can form and sometimes progress to intra-articular flaps. In horses, the most frequent sites are the hindlimb weight-bearing joints, specifically the femorotibial (stifle) and tibiotarsal (hock) joints, where cartilage lesions are often seen. These patterns align with where mechanical stress and growth factors most commonly drive OCD changes in these species. Other joints listed are less typical primary sites for OCD in dogs and horses.

Osteochondrosis dissecans lesions develop in young animals where abnormal endochondral ossification creates focal cartilage defects in weight-bearing joints, with the typical sites differing by species due to how they move and load their joints. In dogs, the shoulder joint (scapulohumeral joint) is a commonly affected location, where cartilage irregularities can form and sometimes progress to intra-articular flaps. In horses, the most frequent sites are the hindlimb weight-bearing joints, specifically the femorotibial (stifle) and tibiotarsal (hock) joints, where cartilage lesions are often seen. These patterns align with where mechanical stress and growth factors most commonly drive OCD changes in these species. Other joints listed are less typical primary sites for OCD in dogs and horses.