By William Grimes
Dr. Leon Root, a widely known orthopedic surgeon whose advice books on back pain and osteoporosis reached a broad public, and who created an ambitious program to screen children in Manhattan and the Bronx for disorders of the bones and joints, died on Monday in Manhattan. He was 86.
The cause was complications of a low blood count, his wife, Paula, said. 
Three years after joining the Hospital for Special Surgery in Manhattan in 1967, Dr. Root was made chief of pediatric orthopedics, a post he held for 27 years. Almost immediately, with his colleague Dr. Peter Bullough, he set up New York City’s first clinic for children with osteogenesis imperfecta, or brittle-bone disease, and expanded the hospital’s cerebral palsy clinic.
He also helped found the rehabilitation department now known as the Leon Root Motion Analysis Laboratory, which collects, analyzes and interprets movement data from patients with orthopedic, rheumatic and neurological disorders to determine the best course of treatment.