Reasons for revision are associated with rerevised total knee arthroplasties: an analysis of 8,978 index revisions in the Dutch Arthroplasty Register

Figures & data

Table 1. Patient characteristics by reason for index rTKA. Values are count (%) unless otherwise specified

Reason for revision ^a Patellar
Factor	Infection (n = 1,538)	Loosening (n = 1,422)	Malposition (n = 1,241)	problems (n = 2,043)	Instability (n = 1,452)	Stiffness (n = 228)	Other (n = 700)	Overall (n = 8,978)
Age, mean (SD)	69 (9.6)	67 (8.9)	66 (9.4)	68 (9.5)	65 (9.5)	64 (9.2)	68 (10.4)	67 (9.6)
Female sex	787 (51)	955 (67)	871 (70)	1,390 (68)	964 (66)	135 (59)	451 (64)	5,787 (65)
Missing	2 (0.1)	1 (0.1)	2 (0.1)	4 (0.2)	3 (0.2)	2 (0.9)	2 (0.3)	17 (0.2)
ASA
I	157 (10)	158 (11)	176 (14)	224 (11)	204 (14)	38 (17)	95 (14)	1,081 (12)
II	853 (56)	972 (68)	837 (67)	1,439 (70)	989 (68)	154 (68)	445 (64)	5,807 (63)
III–IV	504 (33)	273 (19)	205 (17)	341 (17)	233 (16)	30 (13)	138 (20)	1,780 (20)
Missing	24 (1.6)	19 (1.3)	23 (1.9)	39 (1.9)	26 (1.8)	6 (2.6)	22 (3.1)	310 (3.5)
Diagnosis of primary TKA
Osteoarthrosis	1,435 (93)	1,344 (95)	1,169 (94)	1,950 (95)	1,350 (93)	212 (93)	655 (94)	8,446 (94)
Osteonecrosis	6 (0.4)	8 (0.6)	2 (0.2)	4 (0.2)	3 (0.2)	0 (0)	2 (0.3)	26 (0.3)
Posttraumatic	37 (2.4)	27 (1.9)	25 (2.0)	32 (1.6)	45 (3.1)	10 (4.4)	11 (1.6)	191 (2.1)
Rheumatoid arthritis	33 (2.1)	19 (1.3)	16 (1.3)	33 (1.6)	27 (1.9)	4 (1.8)	17 (2.4)	151 (1.7)
Inflammatory arthritides	3 (0.2)	0 (0)	0 (0)	0 (0)	2 (0.1)	1 (0.4)	1 (0.1)	7 (0.1)
Other	10 (0.7)	5 (0.4)	8 (0.6)	6 (0.3)	8 (0.6)	1 (0.4)	4 (0.6)	49 (0.5)
Missing	14 (0.9)	19 (1.3)	21 (1.7)	18 (0.9)	17 (1.2)	0 (0)	10 (1.4)	108 (1.2)
Follow-up years, median	3.0	3.2	3.5	3.7	2.9	2.7	3.7	3.4
IQR	1.5–5.2	1.6–5.6	1.8–5.5	1.9–5.8	1.4–4.9	1.5–4.1	1.8–6.3	1.7–5.5

^a Reasons for revision in the table are those from the hierarchy.

Cumulative repeat revision rate of index rTKA by reason for revision.

Table 2. Cumulative repeat revision rate after rTKA by reason for revision

	Repeat revision rate (95% CI)
Factor	at 1 year	at 8 years	at 8 years ^a
Overall	0.06 (0.05–0.06)	0.19 (0.18–0.20)	–
Infection	0.16 (0.14–0.18)	0.28 (0.25–0.32)	0.18 (0.15–0.21)
Loosening	0.03 (0.02–0.04)	0.16 (0.13–0.19)	0.05 (0.03–0.06)
Malposition	0.03 (0.02–0.04)	0.15 (0.12–0.19)	0.02 (0.01–0.03)
Patellar problems	0.04 (0.03–0.05)	0.15 (0.13–0.17)	0.02 (0.02–0.03)
Instability	0.04 (0.03–0.06)	0.23 (0.17–0.28)	0.07 (0.05–0.09)
Stiffness	0.07 (0.04–0.11)	0.23 (0.15–0.31) ^b	0.07 (0.03–0.14) ^b
Other	0.06 (0.04–0.08)	0.20 (0.16–0.24)	0.01 (0.00–0.04)

^a For the same reason as the index revision.

^b At 6-year follow-up.