On October 4, 2012, One Direction's Niall Horan, 19, revealed on Twitter that he is getting a knee operation: ``Ya know the way I always had a bad knee, added to it playin ball the other day!
132799
Niall Horan gets knee operation;
172507
Josh Hamilton has played through groin injury ``for a while''
87714
Matthews has slight tear in left knee
21352
Tisdale has part of leg amputated due to cancer
16508
Nathan has Tommy John surgery
69853
Rgiii cried after realizing he had ACL surgery
111755
Wayne Rooney to have hernia operation
11452
One Direction proud to be record breakers
25318
Jabbari undergoes knee surgery
41745
Green Day's Billie Joe Armstrong may be in rehab through the new year
57935
Surgeon operated on wrong side of patient
158691
One Direction to write songs with rock band Boyce Avenue for new album
76090
Aj Foyt hospitalized for complications from knee surgery
35825
One Direction's Louis Tomlinson and Niall Horan break down on camera
129593
Jamie to have surgery
111374
Andrew Driver - to undergo hernia surgery.
125269
Ireland lose another player to injury