4) Joe Ansbro
Ansbro broke his neck in a pre-season friendly against Munster on 24 August 2012.
After being taken to hospital straight after the match it was discovered that Ansbro had a triple fracture of the C1 vertebrae. As of 15 May 2013 Ansbro, aged 27, officially retired from rugby union.
Ansbro, having graduated from Cambridge before his professional career, became a Biology teacher and rugby coach at Harrow School.