Fig. 1

Changes in Figure 1 - small text & poor quality image/text ; Figure 2 - poor quality image/text. Please provide replacement of figure files. Otherwise kindly confirm if we can retain the current presentation.the BI scores after surgery in patients. a Comparison in all patients before and after surgery. The 95% confidential interval (C.I.) was 25.4–55.0 in the preoperative and 53.0–80.2 in the postoperative patients; p = 0.017. b Changes in the BI scores in patients capable of ambulation within 7 days. The 95% C.I. was 25.3–60.8 in the preoperative and 68.0–90.1 in the postoperative patients; p = 0.003. c Changes in the BI scores in patients incapable of ambulation within 7 days. The 95% C.I. was − 3.35 to 63.4 in the preoperative and − 13.2 to 54.9 in the postoperative patients; p = 0.33. d Change in the BI scores in patients AWD. The 95% C.I. was 21.9–76.2 in the preoperative and 51.3–91.5 in the postoperative patients; p = 0.15. e Change in the BI scores in patients DOD. The 95% C.I. was 15.4–52.8 in the preoperative and 41.5–83.5 in the postoperative patients; p = 0.11. f Changes in the BI scores in patients who died of disease within 3 months of surgery. The 95% C.I. was − 1.54 to 41.5 in the preoperative and − 33.0 to 68.0 in the postoperative patients; p = 0.31. g Changes in BI scores in patients who died of disease after more than 3 months. The 95% C.I. was 26.7–60.6 in the preoperative and 61.9–87.2 in the postoperative patients; p = 0.006