Complex sentence: In 1991, Shelbourne and Nitz questioned the validity of O’Donoghue's terrible triad study, a review of all arthroscopically confirmed acute injuries of second degree or worse to the ACL and MCL was performed.
Split into simpler sentences: In 1991, Shelbourne and Nitz questioned the validity of O’Donoghue's terrible triad study. A review of all arthroscopically confirmed acute injuries of second degree or worse to the ACL and MCL was performed.