Client Education: Your foal is suffering from septic arthritis which is a bacterial infection of the joint. It appears to only be affecting the right hind fetlock joint. This may have resulted from a small injury over this joint that allowed the bacteria access to the joint. The radiographs did not indicate damage to the surrounding bone. It appears that we've caught the infection early so with aggressive antibiotic therapy the prognosis is good. Discharge Instructions: Continue with dispensed antibiotics for five weeks: potassium penicillin orally every 6 hours and amikacin subcutaneously once daily. Please call to set up a follow-up appointment upon completion of antibiotics. Abstain from strenuous exercise through the duration of antibiotic therapy. Monitor foal for signs of illness: 1) stops suckling 2) elevated rectal temperature ( > 102 F) Monitor Right Hind Fetlock joint for the following: 1) swelling or heat when touched 2) lameness If suspect any recurrence of signs call hospital immediately.