DEAR DR. WELDY’S: My trail horse is 14 years old an has recently developed high ringbone. Is this something that can be successfully treated and what is the long term outlook for soundness?
DEAR READER: High ringbone is arthritis of the pastern joint of the horse. The pastern joint only has a 7 degree movement but when it gets degenerative joint disease that slight movement becomes quite painful to the horse. This joint is a high load — low motion joint and does not respond to intra-auricular injections so treatment can be difficult.
Radiographs and ultrasound are useful in confirming the diagnosis and the severity of the arthritic damage. Often new bony growth forms along the front and sides of the pastern and sometimes can be seen or felt during the lameness exam.
Horses that exert on their lower limbs during sudden stopping and turning are more prone to developing high ringbone. Performance horses can do remarkably well without that 7 degree movement of the pastern joint so high ringbone is one arthritic condition that can be resolved completely by fusing the pastern joint either surgically or allowing time and the bony deposits to gradually fuse the joint. This gradual fusing can take up to a year and surgically the joint can be fused in a matter of weeks with the horse in a cast and box stalled to allow arthritides to occur.
Anti-inflammatory treatment with phenylvbutazone (bute) can be used to decrease inflammation and for long term management while the joint is naturally fusing. Corrective shoeing to ease the break over of the foot decreases the torque on the pastern and can make a big difference in management of high ringbone. Keeping the toe short and rolling the shoe to aid break over often provides great relief to the horse.