We have a '18 filly showing lameness in left hindquarters.  Vet exam and X-rays indicate OCD in high stifle area.  Have you found any diet, supplement, exercise or stall rest to be effective.  Her lameness is worse at times - unknown causes.  How successful is surgery?. Thank you for any info.

The younger they are, the higher the success rate for a positive outcome from surgery. OCD lesions in young horses develop when the softer baby cartilage doesn't turn into bone. The lesion is basically a cartilage lump in the bone. Take it out, the area fills in with bone like it should. Leave it there and no amount of exercise or rest will fix it. I'm skeptical of a feed through supplement fixing the issue like many claim.

I have a 2 year old who has been showing lameless for unknown reasons off and on.  What tests need to be completed in order to diagnose OCD lesions?  Rads, MRI, Ultrasound.  After reading this I would like to have it further reserached on my filly.  Thanks! 

Radiographs are generally definitive. 

Which type of OCD? Not all stifle OCDs are created equally and they carry different prognoses.  Honestly, if the horse is lame now, before even getting into training, I would do surgery. But I'd like to know which type of OCD it is.