Pathological fracture and prognosis of high-grade osteosarcoma of the extremities. An analysis of 2, 847 consecutive cooperative osteosarcoma study group (COSS) patients. (February 2017) - Kelley, L.; Schlegel, M.; Hecker-Nolting, S.; Rössig, C.; Reichardt, P.; Kager, L.; Kühne, T.; Gosheger, G.; Windhager, R.; Specht, K.; Kevric, M.; Nathrath, M.; et al.