injury in American football
... that concussions are the fifth-most common type injury in American football, possibly affecting over 100,000 players each year?
... that <a class="mw-redirect" href="./Concussions" id="mwBWE" rel="mw:WikiLink" title="Concussions">concussions</a> are the fifth-most common type <b id="mwBWI"><a href="./Health_issues_in_American_football" id="mwBWM" rel="mw:WikiLink" title="Health issues in American football">injury in American football</a></b>, possibly affecting over 100,000 players each year?