Total knee arthroplasty: Effect of obesity and other patients’ characteristics on operative duration and outcome

Table 1 Patient’s characteristics

Variable		Frequency (n)	%
Gender	Males	49	24
	Females	155	76
Type of TKR	Unilateral	163	79.9
	Bilateral	41	20.1
Co-morbidities	Hypertension	126	61.8
	Diabetes	84	41.2
	Dyslipidemia	67	32.8
BMI	Normal BMI (BMI value 18.5 to < 25)	9	4.4
	Overweight (BMI value 25 to < 30)	37	18.1
	Obesity class 1 (BMI value 30 to < 35)	47	23
	Obesity class 2 (BMI value 35 to < 40)	61	29.9
	Morbid obesity (BMI value > 40)	50	24.5
Post	DVT	2	1
Operative	PE	0	0
Complications	Infection	2	1

TKR: Total knee replacement; BMI: Body mass index; DVT: Deep venous thrombosis; PE: Pulmonary embolism.

Table 2 Association of patient’s characteristics and duration of surgery

Duration of surgery vs		Unilateral TKR					Bilateral TKR
		n	%	Mean duration	SD	P value	n	%	Mean duration	SD	P value
Gender	Males	35	21.5	124.5	29.2	0.69	14	34.1	224.7	50.2	0.51
	Females	128	78.5	126.9	31.4		27	65.9	212.4	58.3
BMI	Normal BMI	5	3.1	115.8	44.6	0.28	4	9.8	239	51.2	0.66
	(BMI value 18.5 to < 25)
	Overweight	27	16.6	117.1	24		10	24.4	215.3	66.3
	(BMI value 25 to < 30)
	Obesity class 1	40	24.5	125.9	37.3		7	17.1	228.4	33.5
	(BMI value 30 to < 35)
	Obesity class 2	48	29.4	127	29.5		13	31.7	198.8	64.3
	(BMI value 35 to < 40)
	Morbid obesity	43	26.4	133	27.4		7	17.1	226.8	42.5
	(BMI value > 40)
DM	Yes	63	38.7	124.7	30.8	0.59	21	51.2	215.2	56.4	0.87
	No	100	61.3	127.4	33.8		20	48.8	218.1	55.7
HTN	Yes	99	60.7	126.3	29	1	27	65.9	223.8	50.3	0.25
	No	64	39.3	126.3	33.8		14	34.1	202.7	63.7
DLP	Yes	52	31.9	126.7	25.8	0.92	15	36.6	227.1	42.2	0.36
	No	111	68.1	126.2	33.1		26	63.4	210.5	61.7

TKR: Total knee replacement; BMI: Body mass index; DM; Diabetes mellitus; HTN: Hypertension; DLP: Dyslipidemia.

Table 3 Association of patients’ characteristics and length of hospital stay

Length of hospital stay vs		Unilateral TKR					Bilateral TKR
		n	%	Mean	SD	P value	n	%	Mean	SD	P value
Gender	Males	35	21.5	12.6	6.3	0.37	14	34.1	14.6	4.1	0.79
	Females	128	78.5	10.9	3.7		27	65.9	15	6.1
BMI	Normal BMI	5	3.1	10.8	2.5	0.27	4	9.8	12	2.2	0.32
	(BMI value 18.5 to < 25)
	Overweight	27	16.6	10.7	3.6		10	24.4	14.7	6.9
	(BMI value 25 to < 30)
	Obesity class 1	40	24.5	12.6	6.8		7	17.1	16.6	5.6
	(BMI value 30 to < 35)
	Obesity class 2	48	29.4	10.7	3.3		13	31.7	13.5	4.1
	(BMI value 35 to < 40)
	Morbid obesity	43	26.4	10.9	3.3		7	17.1	17.9	6.1
	(BMI value > 40)

TKR: Total knee replacement; BMI: Body mass index.