Functional outcomes after endoprosthetic knee reconstruction following resection of osteosarcoma near the knee

Abstract

Purpose. The aims of this study were to evaluate outcomes of osteosarcoma patients who underwent wide resection and endoprosthetic knee reconstruction, to compare with their own sound sides and controls, and to assess the interrelationships among these parameters.

Method. Twenty patients and 20 matched controls were recruited. Strength and range of motion (ROM) of the knee, gait and Enneking functional score were measured.

Results. The results revealed the operated knees were significantly weaker than sound knees and controls (p < 0.05). The ROM of operated knees, sound knees and controls were 106.28 + 13.08, 134.18 + 7.58, and 137.78 + 7.08 respectively (p < 0.05). Patients' and controls' walking velocity were 54 + 12m/min, and 72 + 6m/min (p < 0.05). Their Enneking score was 21.6 + 2.8 (72% of total score, 30). The ratio of extensor strength of operated/sound knee and isometric hamstring/ quadriceps ratio of operated knee were significantly correlated to the difference of stance-phase duration of bilateral sides (p < 0.05). In addition, the ratio of isometric flexor strength was significantly correlated to Enneking score (p < 0.05). Conclusions. The patients achieved an acceptable recovery in strength and gait in spite of some functional limitation.