In 1992-1994, he served as a senior physician of the Department of Neurosurgery at the University of Maryland and as a Director of the Head and Spinal Injury Unit at the Shock-Trauma Center.
After he returned to Israel Dr. Knoller established the General Trauma Service at the Sheba Medical Center and headed it until 1997. At the same time, he joined the Neurosurgery Department and since that time, he has been promoting cutting-edge head and spine injuries. Dr. Knoller was appointed as a Director of the Spine Surgery Unit in 2000, and since that, he treats and analyzes the entire range of spine and head pathologies.