. 2020 Apr 30;54(6):868–878. doi: 10.1007/s43465-020-00115-5

Table 2.

Ambulatory functions according to dichotomized Koval’s categories (ambulatory outdoors: 1, 2, 3; ambulatory housebound: 4, 5, 6, 7)

Follow-up period	Group	Ambulatory outdoors	Ambulatory housebound	P value^a	P value^b	P value^c
Preoperative period (n = 151)	Group A	58 (75.3%)	19 (26.7%)	N/A
Preoperative period (n = 151)	Group B	56 (76.7%)	18 (24.3%)	N/A
1st year-follow-up (n = 112)	Group A	37 (63.8%)	21 (36.2%)	0.548	0.018
1st year-follow-up (n = 112)	Group B	38 (70.4%)	16 (29.6%)	0.548	0.133
2nd year-follow-up (n = 75)	Group A	27 (67.5%)	13 (32.5%)	N/A	0.323	0.183
2nd year-follow-up (n = 75)	Group B	24 (68.6%)	11 (31.4%)	N/A	0.160	0.032

^aComparison at each follow-up between the two groups

^bComparison with previous year in each group

^cComparison between the preoperative period and the 2nd year-follow-up in each group