At 86, Leon Fleisher is a living legend. A former child prodigy, his is a direct line to Beethoven. He studied with Artur Schnabel, who studied with Theodor Leschetizky, who studied with Carl Czerny, who studied with the master himself.

When he performed with the New York Philharmonic under Pierre Monteux at the age of 16, Monteux called him “the pianistic find of the century.” Fleisher landed a recording contract with Columbia Records and began laying down benchmark recordings of Beethoven, Brahms, Schumann, Grieg and Rachmaninoff with George Szell and the Cleveland Orchestra.

Then everything changed.

Fleisher was diagnosed with focal dystonia in 1964. He gradually lost control of his right hand, throwing his career as a concert pianist into jeopardy. His struggle with the affliction led to a period of soul-searching, and it forced him to diversify. He realized, as Schnabel had espoused, that music came first, the piano second.

Fleisher began channeling his energy into teaching and conducting. He has been a venerable presence at the Peabody Conservatory of Music in Baltimore, the Royal Conservatory of Music in Toronto, and the Curtis Institute of Music in Philadelphia.

Fortunately, the left-hand piano repertoire is extensive, and Fleisher himself has added considerably to it, through commissioned works from contemporary composers or gifts from friends. His new album, “All the Things You Are,” issued by Bridge Records, documents some of these, alongside his performance of Brahms’ towering arrangement of the Bach Chaconne.

The record has become a surprise hit. This week, according to Nielsen Soundscan data, the album ranked second, in terms of overall sales of classical records, in the United States. Billboard ranked it at number 11. The New Yorker’s Alex Ross lauded it as “one of [Fleisher’s] finest hours on record.”

This Sunday night on “The Lost Chord,” I am honored to have Leon Fleisher as my guest. He will join me to talk a little bit about the album and share some of his reflections on music.

Fleisher is an extraordinary individual. Not only has he fought hard to regain control of his right hand – and done so, thanks to experimental treatments with, of all things, Botox – he is quite possibly the most gracious and generous interview subject I’ve ever encountered. It pains me to have had to edit the conversation. But perhaps there will be a follow-up show, in which I’ll air his thoughts on Paul Wittgenstein, Franz Schmidt, Paul Hindemith, Federico Mompou and Erich Wolfgang Korngold.

In the meantime, I hope you’ll join me for “In Good Hands,” this Sunday night at 10 ET, with a repeat Friday morning at 3. Remember, you can enjoy episodes of “The Lost Chord” later as a webcast, at http://www.wwfm.org.