Digital radiographs & MRI of a right hind limb distal medial P1 stress fracture in an 8 year old warmblood jumper. Acute onset 3.5/5 RH lameness while at a show, no edema or tenderness in the limb, nontender to hoof testers RH foot, mildly positive to lower limb flexion, negative to upper limb flexion, blocks 90% sound with low pastern ring block RH, no further improvement with low 4 point block of the RH. Digital Radiographs showed no significant abnormalities. MRI shows significant increase in signal in the distal medial aspect of P1 on the STIR’s and an abnormal trabecular pattern on the T2’s. These findings are consistent with a stress fracture of the distal medial aspect of P1. There may be mild crushing of the subchondral plate of the distal medial condyle of P1 also.
Half-limb cast was applied for 6 weeks, then horse rested for another 10 weeks. Most stress fractures heal in 3-6 months. Horse is still on stall rest at this time. It is possible that this horse could develop osteoarthritis of the pastern joint in the future. If so, surgical fusion of this joint can be performed. Prognosis for return to work as an athlete is excellent after fusion of the pastern joint.