Premise: Adam Best is a fictional character from the BBC soap opera "EastEnders", played by David Proud, the first adult actor with a visible disability to appear regularly in the soap. Both Proud and his character live with spina bifida. The character made his first appearance in the episode broadcast on 10 September 2009 and his last in the one broadcast on 19 July 2010.
Hypothesis: Spina Bifida is a birth defect that occurs when the spine and spinal cord don't form properly and this is what Adam Best suffers from.