The centrodistal (CD) and tarsometatarsal (TMT) joints are often injected individually with a corticosteroid to resolve lameness caused by osteoarthritis (OA). There are no data available regarding diffusion of methylprednisolone (MP) from the TMT joint to the CD joint.
A therapeutic concentration of MP diffuses into the CD joint after methylprednisolone acetate (MPA) is administered into the TMT joint.
To measure the concentration of MP in the CD joint after MPA was administered into the TMT joint.
MPA was administered into a TMT joint of 16 horses. At different times, the ipsilateral CD joint of these horses was injected with a small amount of saline and recovered saline was measured for concentration of MP using high performance liquid chromatography.
Six hours after administration of MPA into the TMT joint, a therapeutic concentration of MP was found in all 10 CD joints sampled at this time.
Administering MPA into the TMT joint only, to treat OA of the distal 2 hock joints, reduces the difficulties and risks associated with centesis of the CD joint.
Horses with pain arising from the distal 2 joints of the hock can be treated by administering MPA into the TMT joint alone.