concave dip in hoof wall

[Becca-84]

My pony (13.3 14yr old haflinger gelding) has a concave ridge running top to bottom down the outside of his off hind. I have only recently noticed it but he has always had problems with this leg and drags the toe, struggles to bring it under home and get the correct canter lead on left rein etc. What could have caused the misshapen hoof and could that be the cause of the weakness, or because of it? He is shod in front but not behind. Any advice welcome

 

[laura_nash]

Not an expert, but the most common cause of a ridge like this (I believe) is a previous injury to the coronet. Providing there is no crack / infection I doubt it is a problem. Still, maybe the cause of the weakness is also related to an injury on that foot / leg in the past?