The three and a half week old Masai giraffe, named Yao, has an infection in his rear left leg and front right shoulder.
Keepers noticed he was limping a week after his birth, but found no signs of an injury.
His limp worsened over time and Dr. Wyatt Winchell, an equine orthopedic specialist with the Brazos Valley Equine Hospital, was called in for an assessment.
Dr. Winchell says Yao has a bone infection that is usually life-threatening in domestic animals.
"Any time you have a single infected joint we become very concerned. When you've got two joints and have bone involvement, as we see in Yao, we become a lot more concerned about his prognosis long-term."
Winchell performed arthroscopic surgery on Yao earlier this week to remove infected tissue and bone.
But he says the young giraffe is not improving as quickly as he'd like.
"The problem we see in young animals, sometimes, is that if they're not bearing weight normally in one leg, they start putting more pressure on the opposite healthy leg and start developing secondary problems that just makes kind of an upward hill battle as we go along here."
Yao was born on February 25th. He is being kept under observation in the giraffe barn with his mother.
The Houston Zoo currently has nine giraffes.