Comparison of clinical outcomes between total hip replacement and total knee replacement

Table 8 Pre-operative and post-operative impact of body mass index category on patient reported outcome measure scores: Total hip replacements

		Normal (n = 14), median (IQR)	Overweight (n = 16), median (IQR)	Obese (n = 34), median (IQR)	Morbidly obese (n = 4), median (IQR)	P value1	H value
HOOS pain	Pre-operative	38 (23-43)	35 (29-44)	30 (25-39)	22.5 (15-X)	0.405	2.917
	Post-operative	99 (65-100)	99 (86-100)	93 (73-97)	97 (97-97)	0.310	3.582
HOOS symptoms	Pre-operative	40 (28-53)	38 (25-53)	40 (30-49)	35 (25-X)	0.720	1.339
	Post-operative	90 (63-100)	98 (69-100)	85 (78-90)	85 (85-85)	0.718	1.349
HOOS ADL	Pre-operative	39 (23-48)	38 (32-42)	33 (27-43)	18 (18-X)	0.277	3.860
	Post-operative	92 (67-99)	98 (73-100)	84 (63-96)	94 (94-94)	0.294	3.712
HOOS Sport/Rec	Pre-operative	28 (20-31)	25 (19-44)	6 (0-25)	13 (6-X)	0.088	6.536
	Post-operative	88 (75-100)	91 (55-100)	63 (34-91)	75 (75-75)	0.252	4.090
HOOS QoL	Pre-operative	25 (6-41)	25 (19-31)	19 (13-25)	13 (0-X)	0.486	2.443
	Post-operative	88 (58-100)	81 (53-98)	69 (38-90)	94 (94-94)	0.376	3.106
Overall HOOS	Pre-operative	35.9 (29.9-41.7)	36.0 (24.8-38.5)	25.7 (20.7-33.3)	25.0 (12.8-X)	0.267	3.950
	Post-operative	91.2 (88.8-100)	95.1 (68.3-98.6)	79.0 (60.4-90.0)	89.0 (89.0-89.0)	0.256	4.047
WOMAC pain	Pre-operative	40 (33-63)	38 (31-53)	38 (30-45)	25 (15-X)	0.445	2.673
	Post-operative	100 (68.8-100)	100 (85-100)	90 (75-98)	95 (95-95)	0.332	3.417
WOMAC stiffness	Pre-operative	38 (19-50)	38 (25-50)	25 (25-38)	25 (13-X)	0.377	3.099
	Post-operative	94 (56-100)	94 (66-100)	75 (75-88)	75 (75-75)	0.483	2.459
WOMAC function	Pre-operative	39.7 (30.1-54.4)	39.7 (32.0-43.8)	33.1 (26.8-44.1)	17.6 (17.6-X)	0.267	3.951
	Post-operative	91.9 (69.1-99.3)	98.5 (73.2-99.6)	83.8 (63.2-95.6)	94.1 (94.1-94.1)	0.313	3.562
Oxford hip score	Pre-operative	23 (12-29)	18 (13-22)	13 (10-19)	7 (5-X)	0.046a	8.001
	Post-operative	44 (35-47.75)	44 (36-48)	39 (31-45)	47 (47-47)	0.275	3.882
EQ-5D index	Pre-operative	0.527 (0.059-0.699)	0.481 (0.235-0.568)	0.289 (0.210-0.420)	0.169 (-0.199-X)	0.305	3.624
	Post-operative	1 (0.659-1)	1 (0.685-1)	0.750 (0.639-0.892)	1 (1-1)	0.158	5.198
EQ-5D VAS	Pre-operative	60 (40-80)	80 (60-85)	65 (40-74)	65 (40-X)	0.250	4.105
	Post-operative	93 (60-100)	94 (71-100)	80 (75-84)	90 (90-90)	0.106	6.114
SF-12 PCS	Pre-operative	31.8 (19.7-37.1)	26.8 (22.5-37.9)	24.1 (21.4-27.6)	25.0 (21.7-X)	0.370	3.144
	Post-operative	54.8 (40.5-56.0)	49.3 (36.4-55.3)	43.9 (28.0-54.8)	49.3 (49.3-49.3)	0.590	1.914
SF-12 MCS	Pre-operative	59.5 (51.2-63.1)	53.5 (39.9-61.7)	47.4 (40.1-52.7)	32.3 (16.7-X)	0.075	6.919
	Post-operative	57.5 (55.9-59.8	59.8 (55.7-60.8)	57.7 (50.2-59.8)	60.8 (60.8-60.8)	0.334	3.396

¹Kruskal Wallis H test.

^aStatistically significant P < 0.05.

IQR: Interquartile range; HOOS: Hip Osteoarthritis Outcome Score; ADL: Activities of daily living; Sport/Rec: Sports and recreation; QoL: Quality of life; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; EQ-5D: EuroQol-5D index; VAS: Visual Analogue Scale; SF-12: Short Form 12 item survey; PCS: Physical component summary; MCS: Mental component summary.