Readmission rate and early complications in patients undergoing total knee arthroplasty: A retrospective study

Table 1 Characteristics of the study population

Study variable		Cases, n	Percent, %
Age in year	≤ 40	5	0.8
	41-50	43	7.1
	51-60	197	32.3
	61-70	251	41.2
	71-80	104	17.1
	> 80	9	1.5
Sex	Female	420	69
	Male	189	31
Body mass index in kg/m2	< 24.9 (normal)	249	40.8
	25-29.9 (overweight)	332	54.5
	> 30 (class 1 obesity)	28	4.6
Diagnosis	Osteoarthritis	593	97.4
	Rheumatoid arthritis	16	2.6
Laterality	Bilateral	304	49.9
	Unilateral	305	50.1
Duration of complaint	< 1	3	0.5
	1-2.0	26	4.3
	2-5.0	168	27.6
	5-10.0	239	39.2
	> 10	173	28.4
Charlson comorbidity index	< 2	399	65.5
	2-3.0	156	25.6
	> 4	54	8.9
Length of stay in day	6	297	48.8
	7	306	50.2
	8	4	0.7
	10	1	0.2
	13	1	0.2

Table 2 Unplanned visits within 30 days after total knee arthroplasty

Unplanned visit after TKA within 30 days	Follow-up	Cases, n	Percent, %
Occurred	No	593	97.40
	Yes	16	2.60
Reason	Febrile illness	2	0.40
	Urinary tract infection	2	0.40
	Neurological issues	1	0.20
	Lower back ache	1	0.20
	Post TKA pain	3	0.60
	Wound complications	5	1.00
	Other surgery-related complications	2	0.40

TKA: Total knee arthroplasty.

Table 3 Unplanned visits within 90 days after total knee arthroplasty

Unplanned visit after TKA within 90 days	Follow-up	Cases, n	Percent, %
Occurred	No	815	95.40
	Yes	8	4.60
Reason for unplanned visits within 90 days	Febrile illness	3	0.60
	Urinary tract infection	3	0.60
	Neurological issues	2	0.40
	Generalized body weakness	1	0.20
	Lower back ache	2	0.40
	Soft tissue injury over knee	2	0.40
	Post TKA pain	7	1.40
	Wound complications	5	1.00
	Other surgery-related complication	3	0.60

TKA: Total knee arthroplasty.

Table 4 Reasons for readmissions at 90 days

Reasons for readmissions within 90 days	Cases, n	Percent, %
Febrile illness	2	0.40
Neurological issues	2	0.40
Talonavicular degeneration	1	0.20
Soft tissue injury over the knee	2	0.40
Wound complications	4	0.80

Table 5 Comparisons of readmissions after total knee arthroplasty in various studies

Readmission after TKA	On 30-day follow-up	On 90-day follow-up
Our study	1.1% (n = 7)	1.8% (n = 11)
Urish et al[19]	4% (n = 703)	5.8% (n = 1209)
Cassard et al[16]	3.3% (n = 2) outpatient	NA
	4.9% (n = 25) inpatient
Avram et al[15]	2% (n = 55)	NA
Workman et al[26]	2.8% (n = 210)	NA
Ali and Bottle[21]	6.0% (n = 37195)	NA
D'Apuzzo et al[22]	5.8% (n = 22076)	NA

TKA: Total knee arthroplasty; NA: Not available.

Table 6 Comparisons of unplanned readmissions after total knee arthroplasty in various studies

Unplanned readmission after TKA	On 30-day follow-up	On 90-day follow-up
In our study	1.1% (n = 7)	1.4% (n = 9)
Schairer et al[18]	4% (n = 57)	8% (n = 118)
Urish et al[19]	4% (n = 703)	5.8% (n = 1209)
Cassard et al[16]	3.3% (n = 2) outpatient	NA
	4.9% (n = 25) inpatient
D'Apuzzo et al[22]	5.8% (n = 22076)	NA
Odum and Springer[27]	12% outpatient1	NA
	6% inpatient1
Ali and Bottle[21]	6.0% (n = 37195)	NA
Workman et al[26]	2.8% (n = 210)	NA
Avram et al[15]	2% (n = 55)	NA
Yohe et al[20]	4.7% (n = 566)	NA

¹Number data not reported.

NA: Not available; TKA: Total knee arthroplasty.