Measurement of morphological parameters of giant cell tumor of bone in the knee

The aim of the present study was to characterize the morphological parameters of giant cell tumor of bone (GCTB) in the knee. The imaging data of 250 patients with GCTB in the knee were retrospectively reviewed, and the morphological parameters were analyzed. The study included 137 cases with GCTB in the distal femur and 113 cases with GCTB in the proximal tibia. The maximal longitudinal diameter of the tumor was 6.616±2.322 cm in the femur group and 5.738±2.278 cm in the tibia group (P=0.003). The maximal transverse diameter in the two groups was 4.865±1.525 and 4.313±1.309 cm, respectively (P=0.003). The shortest distance from the articular surface (SDAS) in the two groups was 0.381±0.404 and 0.280±0.328 cm, respectively (P=0.035), whereas the longest distance from the articular surface in the two groups was 6.924±2.135 and 5.878±1.825 cm, respectively (P=0.001). There were statistically significant differences between the two groups in terms of the range of SDAS (P=0.043). Additionally, the incidence of pathological fractures in the femur was higher compared with that in the tibia (P=0.001), and the incidence of pathological fractures in the two groups gradually increased with the increase in lesion diameter. GCTB in the distal femur was larger compared with that in the proximal tibia, whereas GCTB in the tibia was closer to the articular surface compared with that in the femur. Furthermore, the incidence of pathological fractures in the femur was higher compared with that in the tibia.