The Tori & Dean star received three stitches, in addition to the collapsed lung. He injured himself Tuesday after smashing his chest into the bars on his bike in what he called a "freak accident" on his Twitter.
"Let's just say, I won't be dirt biking anymore," he wrote on Friday.
McDermott, 43, and Spelling, 37, have been married for four years and have two children together: 3-year-old Liam and 2-year-old Stella. McDermott also has another son, Jack, from his first marriage.