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

Table 7 Pre-operative and post-operative impact of body mass index category on patient reported outcome measure scores: Total knee replacements

		Normal (n = 8), median (IQR)	Overweight (n = 24), median (IQR)	Obese (n = 31), median (IQR)	P value1	H value
KOOS pain	Pre-operative	41 (22-51)	38 (26-49)	33 (22-42)	0.230	2.936
	Post-operative	97 (95-100)	92 (73-97)	88 (72-98)	0.046a	6.160
KOOS symptoms	Pre-operative	32 (23-62)	38 (21-56)	32 (22-43)	0.701	0.712
	Post-operative	91 (86-95)	89 (86-93)	86 (79-93)	0.129	4.098
KOOS ADL	Pre-operative	40 (25-53)	38 (34-45)	40 (26-43)	0.466	1.527
	Post-operative	96 (89-99)	91 (78-97)	87 (76-96)	0.214	3.079
KOOS Sport/Rec	Pre-operative	5 (0-63)	8 (0-25)	5 (0-20)	0.621	0.952
	Post-operative	75 (60-100)	73 (51-84)	65 (45-88)	0.582	1.083
KOOS QoL	Pre-operative	19 (0-44)	19 (6-31)	6 (6-19)	0.302	2.394
	Post-operative	91 (75-99)	75 (63-100)	63 (47-81)	0.032a	6.881
Overall KOOS	Pre-operative	36.5 (12.1-51.1)	32.2 (20.8-43.8)	26.6 (16.7-33.7)	0.354	2.075
	Post-operative	87 (80-97)	81.3 (67.2-92.0)	79.9 (64.1-84.8)	0.208	3.139
WOMAC pain	Pre-operative	45 (25-54)	40 (30-50)	35 (25-50)	0.332	2.206
	Post-operative	100 (95-100)	90 (75-99)	90 (79-100)	0.045a	6.186
WOMAC stiffness	Pre-operative	38 (6-59)	25 (25-47)	25 (25-38)	0.704	0.702
	Post-operative	100 (75-100)	75 (63-100)	75 (63-88)	0.084	4.960
WOMAC function	Pre-operative	39.7 (25.0-53.3)	38.2 (34.1-45.2)	39.7 (26.5-44.1)	0.521	1.302
	Post-operative	97.1 (93.0-100)	91.2 (78.3-97.1)	86.0 (75.7-97.1)	0.125	4.154
Oxford knee score	Pre-operative	17 (11-23)	15 (11-19)	14 (11-19)	0.566	1.137
	Post-operative	39 (38-40)	42 (33-45)	39 (33-43)	0.559	1.165
EQ-5D index	Pre-operative	0.502 (0.107-0.630)	0.304 (0.215-0.479)	0.356 (0.206-0.535)	0.606	1.002
	Post-operative	0.837 (0.821-1)	0.837 (0.735-1)	0.767 (0.633-0.939)	0.260	2.696
EQ-5D VAS	Pre-operative	80 (65-80)	80 (50-90)	60 (50-70)	0.139	3.940
	Post-operative	80 (74-85)	85 (70-95)	85 (70-90)	0.652	0.856
SF-12 PCS	Pre-operative	29.6 (24.8-36.4)	28.2 (23.9-37.8)	27.2 (21.6-29.9)	0.257	2.714
	Post-operative	49.0 (44.0-51.7)	46.9 (30.1-53.3)	38.5 (32.5-49.6)	0.379	1.942
SF-12 MCS	Pre-operative	48.2 (38.1-54.6)	50.1 (40.0-59.6)	45.0 (38.6-54.1)	0.692	0.737
	Post-operative	58.6 (53.4-60.6)	59.3 (44.2-62.3)	57.8 (51.2-60.5)	0.897	0.208

¹Kruskal Wallis H test.

^aStatistically significant P < 0.05.

KOOS: Knee Osteoarthritis Outcome Score; ADL: Activities of daily livin; 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.