The star — who is also a dad to daughters Della Rose Joel, 9, and Remy Anne Joel, 7, with wife Alexis Roderick — is undergoing specific physical therapy under his doctor's instructions. He has also been "advised to refrain from performing during this recovery period."

The NBC sketch comedy series closed out its landmark 50th season with the 'Eleanor the Great' director as host and the "Tití Me Preguntó" singer as the night's musical guest.

Singer-songwriter Billy Joel has said he has been diagnosed with a neurological condition that prevents him from performing for some time. He is suffering from normal pressure hydrocephalus (NPH), where the fluids inside your brain cavities are overproduced,