Radiologically Hyperdense Zones of the Patella Seem to Be Partial Osteonecroses Subsequent to Fracture Treatment - Schüttrumpf, Jan Philipp; Behzadi, Cyrus; Balcarek, Peter; Walde, Tim Alexander; Frosch, Stephan; Wachowski, Martin Michael; Stürmer, Klaus Michael; Frosch, Karl-Heinz (The Journal of Knee Surgery, 2013)