SHANGHAI, China — Doctors in Shanghai on Tuesday were considering surgery options for a 2-month-old boy born with an unusually well-formed third arm. Neither of the boy’s two left arms is fully functional and tests have so far been unable to determine which was more developed, said Dr. Chen Bochang, head of the orthopedics department at Shanghai Children’s Medical Center.

A doctor inspects a 59-day-old baby boy who was born with three arms, at a hospital in Shanghai, in east China Monday. AP Photo.

“His case is quite peculiar. We have no record of any child with such a complete third arm,” Chen said in a telephone interview. The boy, identified only as “Jie-jie,” also was born with just one kidney and may have problems that could lead to curvature of the spine, local media reports said. Jie-jie cried when either of his left arms was touched, but smiled and responded normally to other stimuli, the reports said. Chen said doctors hoped to work out a plan for surgery, but the boy’s small size made it impossible to perform certain tests that would help them prepare. Media reports said other children have been reported born with additional arms and legs, but in those cases it was clear what limb was more developed. Chen’s hospital is one of China’s most experienced in dealing with unusual birth defects, including separating conjoined twins.