High efficiency pathway for lower limb orthopedic surgery: A matched historic cohort study

Table 1 Pre- and post-match baseline demographic characteristics

	Pre-match			Post-match
	Traditional (n = 553)	High efficiency (n = 838)	SD	Traditional (n = 429)	High efficiency (n = 429)	SD
Female, n (%)	342 (63.9)	619 (73.9)	0.27	289 (67.4)	289 (67.4)	0
Age (year), mean (SD)	52.3 (15.4)	55.9 (14.1)	0.26	54.2 (14.7)	53.9 (14.9)	0.02
BMI (kg/m2), mean (SD)	29.5 (6.5)	28.0 (5.6)	0.26	29.2 (6.3)	28.3 (5.7)	0.16
ASA I and II, n (%)	380 (68.7)	622 (74.2)	0.13	294 (69.9)	300 (68.5)	0.03
Surgery below ankle, n (%)	317 (57.3)	718 (85.7)	0.81	314 (73.2)	314 (73.2)	0

BMI: Body mass index; ASA: American Society of Anesthesiologists.

Table 2 Distribution of surgical procedures before and after matching, n (%)

	Pre-match		Post-match
	Traditional (n = 553)	High efficiency (n = 838)	Traditional (n = 429)	High efficiency (n = 429)
Below ankle	318 (57.5)	718 (85.6)	314 (73.2)	314 (73.2)
Soft tissue excision	14 (2.5)	48 (5.7)	14	20
Toe or foot hardware removal	26 (4.7)	69 (8.2)	26	30
Toe or foot arthrodesis	147 (26.6)	256 (30.5)	145	108
Toe open reduction	17 (3.1)	39 (4.7)	17	21
Toe or foot osteotomy	81 (14.6)	288 (34.4)	81	127
Foot tendon repair	33 (6.0)	18 (2.1)	31	8
At or above ankle	235 (42.5)	120 (14.3)	115 (26.8)	115 (26.8)
Ankle arthroscopy	20 (3.6)	6 (0.8)	8	6
Ankle or tibial hardware removal	46 (8.3)	100 (11.9)	23	95
Ankle arthrodesis	25 (4.5)	0 (0)	10	0
Ankle ligament repair	8 (1.4)	1 (0.1)	4	1
Ankle or tibial osteotomy	25 (4.5)	2 (0.2)	11	2
Ankle open reduction	111 (20.0)	11 (1.3)	59	11

Table 3 Pre- and post-match outcomes

	Pre-match1		Post-match2		Mean difference or odds ratio3 (95%CI)	P value	E value (5%CL)
	Traditional (n = 553)	High efficiency (n = 838)	Traditional (n = 429)	High efficiency (n = 429)
Total recovery time (minute), median [IQR]	133 [102-169]	68 [51-90]	133 [100-171]	67 [49-88]	-63 (-69 to -57)	< 0.001a	6.2
Preoperative time (minute), median [IQR]	40 [32-54]	42 [31-58]	39 [32-52]	41 [31-59]	-2 (-4 to 1)	0.17
Operating time (minute), median [IQR]	59 [43-76]	40 [27-52]	59 [43-77]	39 [27-51]	-20 (-23 to -17)	< 0.001a	4.2
Total length of stay (minute), median [IQR]	324 [279-380]	238 [203-275]	320 [275-378]	236 [205-273]	-84 (-92 to -75)	< 0.001a	5.7
Phase 1 recovery utilization, n/total, n (%)	458/553 (82.8)	45/838 (5.4)	403 (93.4)	26 (6.1)	0.016 (0.010-0.026)	< 0.001a	15.3
Opioid utilization, n/total, n (%)	175/553 (31.6)	87/745 (11.7)	139 (32.4)	45 (10.5)	0.24 (0.17-0.36)	< 0.001a	3.5

¹Outcomes under pre-matched samples were unadjusted, presented as median and IQR, or number and percentage.

²Outcomes from matched samples were adjust from multivariable regression model taking age, body mass index, sex, American Society of Anesthesiologists and surgical types as co-variates, presented as median and IQR, or number and percentage.

³Mann-Whitney U test was used for continuous outcomes and Fisher’s exact test for categorical outcomes.

^aP < 0.05 indicates statistically significant, compared post-matched samples between high efficiency and traditional groups.

Table 4 Pre- and post-match baseline demographic characteristics in the below ankle or at and above ankle surgery subgroup

	Pre-match			Post-match
	Traditional	High efficiency	SD	Traditional	High efficiency	SD
Below ankle	n = 317	n = 718		n = 312	n = 312
Female, n (%)	224 (70.1)	545 (75.9)	0.12	220 (70.5)	230 (73.7)	0.07
Age (year), mean (SD)	56.9 (13.4)	57.5 (13.1)	0.04	56.8 (13.5)	57.3 (12.9)	0.05
BMI (kg/m2), mean (SD)	29.7 (6.5)	28.0 (5.6)	0.30	29.3 (6.0)	28.9 (6.1)	0.07
ASA I and II, n (%)	198 (62.4)	522 (72.7)	0.23	198 (63.5)	200 (64.1)	0.04
Above ankle	n = 236	n = 120		n = 114	n = 114
Female, n (%)	118 (50.0)	74 (61.7)	0.24	68 (59.6)	70 (61.4)	0.04
Age (year), mean (SD)	46.1 (15.8)	46.5 (16.6)	0.03	45.6 (16.2)	45.8 (16.2)	0.01
BMI (kg/m2), mean (SD)	29.2 (6.4)	28.4 (5.7)	0.15	28.8 (6.1)	28.6 (5.6)	0.03
ASA I and II, n (%)	182 (77.1)	100 (83.3)	0.17	98 (86.0)	96 (84.2)	0.05

BMI: Body mass index; ASA: American Society of Anesthesiologists.

Table 5 Post-matched surgical procedures between high efficiency and traditional groups, n (%)

	Traditional	High efficiency
Below ankle	n = 312	n = 312
Soft tissue excision	14 (4.5)	15 (4.8)
Toe or foot hardware removal	26 (8.3)	27 (8.7)
Toe or foot arthrodesis	141 (45.2)	130 (41.2)
Toe or foot open reduction	17 (5.4)	24 (7.7)
Toe or foot osteotomy	81 (26.0)	111 (35.6)
Foot tendon repair	33 (10.6)	5 (1.6)
At or above ankle	n = 116	n = 116
Ankle arthroscopy	10 (8.6)	6 (5.2)
Ankle or tibial hardware removal	19 (16.4)	96 (82.8)
Ankle arthrodesis	14 (12.1)	0 (0)
Ankle ligament repair	3 (2.6)	1 (0.9)
Ankle or tibial osteotomy	14 (12.1)	2 (1.7)
Ankle open reduction	56 (48.3)	11 (9.5)

Table 6 Measured outcomes in pre- and post-matched samples with difference in mean and odds ratios in below ankle procedures

	Pre-match1		Post-match2		Mean difference (95%CI)	P value3	E value (5%CL)
	Traditional (n = 317)	High efficiency (n = 718)	Traditional (n = 312)	High efficiency (n = 312)
Total recovery time (minute), median [IQR]	137 [101-173]	69 [51-92]	137 [101-173]	68 [51-92]	-63 [-70 to -56]	< 0.001a	5.8
Preoperative time (minute), median [IQR]	39 [32-51]	42 [31-58]	40 [32-51]	42 [33-56]	-2 [-5 to 1]	0.12	3.5
Operating time (minute), median [IQR]	59 [41-77]	41 [28-52]	59 [41-77]	41 [28-54]	-17 [-20 to -13]	< 0.001a
Total length of stay (minute), median [IQR]	321 [278-378]	240 [204-275]	321 [278-378]	242 [203-271]	-84 [-94 to -74]	< 0.001a	5.8
Phase 1 recovery utilization, n (%)	249 (78.5)	32 (4.5)	245 (78.5)	15 (4.8)	0.014 (0.007-0.025)	< 0.001a	16.4
Opioid utilization, n (%)	96 (30.2)	71 (9.9)	96 (30.8)	30 (9.6)	0.24 (0.15-0.38)	< 0.001a	3.5

¹Outcomes under pre-matched samples were unadjusted, presented as median and IQR, or number and percentage.

²Outcomes from matched samples were adjust from multivariable regression model taking age, body mass index, sex, American Society of Anesthesiologists and surgical types as co-variates, presented as median and IQR, or number and percentage.

³Mann-Whitney U test was used for continuous outcomes and Fisher’s exact test for categorical outcomes.

^aP < 0.05 as statistically significant, compared post-matched samples between high efficiency and traditional groups.

Table 7 Measured outcomes in pre- and post-matched samples with difference in mean in above ankle procedures

	Pre-match1		Post-match2		Mean difference (95%CI)	P value	E value (5%CL)
	Traditional (n = 235)	High efficiency (n = 120)	Traditional (n = 116)	High efficiency (n = 116)
Total recovery time (minute), median [IQR]	130 [103-166]	60 [48-82]	131 [103-166]	60 [48-81]	-67 (-77 to -56)	< 0.001	7.9 (5.9)
Preoperative time (minute), median [IQR]	42 [32-59]	42 [31-59]	41 [33-59]	41 [31-60]	0 (-5 to 5)	0.97	4.6 (3.4)
Operating time (minute), median [IQR]	59 [46-73]	34 [26-45]	58 [44-78]	35 [27-46]	-22 (-27 to -17)	< 0.001
Total length of stay (minute), median [IQR]	330 [281-383]	225 [200-274]	327 [286-378]	226 [200-274]	-101 (-117 to -82)	< 0.001	7.6 (5.6)

¹Outcomes under pre-matched samples were unadjusted, presented as median and IQR, or number and percentage.

²Outcomes from matched samples were adjust from multivariable regression model taking age, body mass index, sex, American Society of Anesthesiologists as co-variates, presented as median and IQR, or number and percentage.

Table 8 Measured outcomes in pre- and post-matched samples with difference in odds ratios in above ankle procedures, n (%)

Recovery events	Traditional	High efficiency	Traditional	High efficiency	Odds ratio (95%CI)	P value1	E value (5%CL)
Phase 1 recovery utilization, n/total	209 (88.9)	13 (10.8)	98 (84.5)	12 (10.3)	0.022 (0.009-0.049)	< 0.001a	13.0 (8.5)
Opioid utilization, n/total	79 (33.6)	16 (13.3)	44 (37.9)	16 (13.8)	0.26 (0.13-0.52)	< 0.001a	3.3 (2.1)

¹Mann-Whitney U test was used for continuous outcomes and Fisher’s exact test for categorical outcomes.

^aP < 0.05 vs post-matched samples between high efficiency and traditional groups.