Makes (Horse) Sense To Me

Two horse enthusiasts were having a conversation. "I found a veterinarian that specializes in racehorses. Their legs and joints can get very tender and fragile as they get old. My 'ol Betsy is starting to have problems trotting." "What's so great about this place?" "They're professional, experienced, and they have extremely fast service." "So what's this place called?" "Po-Knee Express!"