As you can read from his story, he actually had scoliosis as a teenager, and had Harrington rod surgery as a teen as well. His daughter, a dancer, also had scoliosis surgery as a teen.
He will likely also be discussing / tweeting about the National Scoliosis Foundation (http://www.scoliosis.org), which helps to promote early scoliosis detection and treatment to help decrease suffering due to spinal deformities, and also decrease need for scoliosis surgery.
2022 EST update
Ken Rosenthal did get a chance to specifically mention in a separate TWEET, he National Scoliosis Foundation: https://twitter.com/Ken_Rosenthal/status/1049041954850443265