Anatomical two-bundle medial patellofemoral ligament reconstruction with hardware-free patellar graft fixation: technical note and preliminary results. - Hinterwimmer, Stefan; Imhoff, Andreas; Minzlaff, Philipp; Saier, Tim; Rosenstiel, Nikolaus; Hawe, Wolfried; Feucht, Matthias (Knee Surgery, Sports Traumatology, Arthroscopy, 2013)