1. Interactive Case Tutorial

2.  Review the history and signalment for the client  Evaluate the radiographs provided  Explore the interactive images and compare the answers given with your own interpretations  Answer the questions regarding a diagnosis and recommendations  Review the radiologist’s findings

3.  Signalment: 13 month old, FS, Newfoundland  History: 4-5 week history of left thoracic limb lameness  Study: Lateral and caudocranial views of the left shoulder  Technique note: the medial widening of the joint on the caudocranial view is positional artifact – the shoulder does not have true collateral ligaments (supporting muscle/tendons act as such) and thus has more inherent laxity

4. Faintly mineralized clavicular remnant Small mineral fragments Flattened caudal aspect humeral head End-on vein Normal physis Moderate subchondral sclerosis

5.  Provide a diagnosis based on your findings. Submit Osteochondritis dissecans (OCD) of the left humeral head Feedback Continue

6.  Provide your recommendation for this client. Submit Radiograph the right shoulder as this is often a bilateral lesion. Surgical management of the left humeral head OCD. Feedback Continue

7.  Severe flattening of the caudal aspect of the humeral head  Small mineral fragments at level of flattening  Moderate subchondral sclerosis of the humeral head

8.  Radiographs of the right shoulder obtained  Open arthrotomy with a caudolateral approach was performed on the left shoulder. The mineralized flap was removed with a curette and hemostat. The edges of the defect were beveled slightly and the subchondral bone was debrided. All loose fragments were removed, the caudal joint pouch explored and the joint flushed and closed.  The patient recovered and was placed on 2 week strict exercise restriction followed by gradual increase in activity.