Kids often get knee pain. When it persists, an X-ray may show a lesion of the articular cartilage: the bearing surface of the joint. That lesion is usually called Osteochondritis dissecans, a terrible and misleading name that implies inflammation (itis) and drying out (dissecans), though neither is present in the condition.
We take sunlight for granted. In our hubris we produce our own version of light and imagine it an acceptable replacement. Oddly, we have a greater appreciation of plants' need for natural light than our own. Recent research now adds depression to the already lengthy list of illnesses associated with inadequate sunlight.
The one common element to all of these extraordinary recoveries was the person's positive state of mind, whereby nothing was going to get in their way or prevent them from returning to their previous lifestyles; which enabled them to pursue all of their goals, some of them even bigger and better than before.