Young patients with hematologic and lymphatic malignancies have an increased risk of hip and knee arthroplasty

Figures & data

Figure 1. Radiograph of hip joints in 54-year-old female patient with acute lymphoblastic leukemia showing osteonecrosis of the left femoral head (arrow) (A). Cross-section of the femoral head during the total hip arthroplasty procedure showing osteonecrotic lesion and partial collapse of the femoral head (arrow) (B).

Figure 2. Flowchart of included patients with total joint arthroplasty performed between 2000 and 2012 after cancer diagnosis.

Table I. Patients with total joint arthroplasty performed between 2000 and 2012 after cancer diagnosis.

	Patients with cancer
Variables	Total		Hematologic and lymphatic malignancies		Other cancers		Patients with no cancer
No. of TJA	18 981		1261		17 720		170 854
No. of patients	15 034		1029		14 005		130 515
– Females	9301	(61.9%)	595	(57.8%)	8706	(62.2%)	82 815	(63.5%)
– Person years	2 323 512		193 973		2 129 539		68 752 631
– Mean age*	69.7	(SD 9.2)	68.3	(SD 10.6)	69.9	(SD 8.9)	66.7	(SD 10.8)
– Hip joint	8888	(46.8%)	724	(57.4%)	8164	(46.1%)	79 094	(46.3%)
– Knee joint	10 093	(53.2%)	537	(42.6%)	9556	(53.9%)	91 760	(53.7%)

SD, standard deviation; TJA, total joint arthroplasty.

*Age at the time of total joint arthoplasty.

Table II. Standardized incidence ratios for all hematologic and lymphatic malignancies by age group.

Age group	Person years	Observed # of TJA	Expected # of TJA	SIR (obs/exp)	95% CI
0–19	10 411	5	0.0	112	36.2–260
20–34	19 570	31	1.1	27.7	18.8–39.2
35–49	25 619	50	14.7	3.4	2.5–4.5
50–64	56 144	281	238	1.2	1.1–1.3
65–79	60 113	712	770	0.9	0.9–1.0
80–	22 114	182	197	0.9	0.8–1.1
Total	193 972	1261	1221	1.0	1.0–1.1

CI, confidence interval; SIR, standardized incidence ratio; TJA, total joint arthroplasty.

Table III. Standardized incidence ratios for cancers other than hematologic or lymphatic malignancies by age group.

Age group	Person years	Observed # of TJA	Expected # of TJA	SIR (obs/exp)	95% CI
0–19	12 514	0	0.1	0	n/a
20–34	38 986	9	2.1	4.2	1.9–8.1
35–49	159 479	146	90.4	1.6	1.4–1.9
50–64	614 839	2989	2586	1.2	1.1–1.2
65–79	889 760	11 218	11 430	1.0	0.96–1.00
80–	413 961	3358	3750	0.9	0.87–0.93
Total	2 129 539	17 720	17 858	1.0	0.98–1.01

CI, confidence interval; n/a, not applicable; SIR, standardized incidence ratio; TJA, total joint arthroplasty.

Table IV. Standardized incidence ratios for hematologic and lymphatic malignancies by malignancy type.

	ALL
Age group	Per. Years	Obs.#	Exp.#	SIR	95% (CI)
0–19	6537	4	0.0	142	38.7–364
20–34	5732	13	0.3	39.6	21.1–67.7
35–49	1984	7	1.0	7.3	2.9–14.9
50–64	695	10	2.9	3.4	1.6–6.3
65–79	336	5	4.3	1.16	0.4–2.7
80–	10	0	0.1	0	n/a
Total	14 994	39	8.7	4.5	3.2–6.2
	AML					CML					CLL
Age group	Per. Years	Obs.#	Exp.#	SIR	95% (CI)	Per. Years	Obs.#	Exp.#	SIR	95% (CI)	Per. Years	Obs.#	Exp.#	SIR	95% (CI)
0–19	793	0	0.0	0	n/a	101	0	0.0	0	n/a	3	0	0.0	0	n/a
20–34	951	6	0.1	110	40.4–240	390	3	0.0	134	27.7–392	53	0	0.0	0	n/a
35–49	1549	14	0.9	15.8	8.6–26.5	979	2	0.6	3.6	0.4–12.9	652	2	0.4	5.4	0.65–19.3
50–64	2254	21	9.6	2.2	1.4–3.4	1518	7	6.4	1.1	0.44–2.24	4634	17	19.6	0.9	0.5–1.4
65–79	1538	19	19.7	1.0	0.6–1.5	922	9	11.8	0.8	0.35–1.45	8662	93	111	0.8	0.7–1.0
80–	293	1	2.6	0.4	0.1–2.1	291	1	2.6	0.4	0.01–2.15	3695	31	32.9	0.9	0.6–1.3
Total	7378	61	32.8	1.9	1.4–2.4	4201	22	21.4	1.03	0.64–1.6	17 699	143	164	0.9	0.7–1.0
	Non-Hodgkin’s lymphoma					Hodgkin’s lymphoma					Myeloma
Age group	Per. Years	Obs.#	Exp.#	SIR	95% (CI)	Per. Years	Obs.#	Exp.#	SIR	95% (CI)	Per. Years	Obs.#	Exp.#	SIR	95% (CI)
0–19	1628	1	0.0	143	3.6–795	1047	0	0.0	0	n/a	1	0	0.0	0	n/a
20–34	4102	3	0.2	12.8	2.6–37.3	8057	5	0.5	10.8	3.5–25.3	43	1	0.0	406	10.3–2261
35–49	10 418	18	6.0	3.0	1.8–4.8	8805	5	5.0	1.0	0.3–2.3	799	2	0.5	4.37	0.5–15.8
50–64	31 040	138	132	1.1	0.9–1.2	9213	28	39.0	0.7	0.5–1.0	5075	45	21.5	2.09	1.5–2.8
65–79	35 301	449	452	1.0	0.9–1.1	4141	38	53.1	0.7	0.5–1.0	7383	79	94.6	0.84	0.7–1.0
80–	13 667	121	122	1.0	0.8–1.2	939	4	8.4	0.5	0.1–1.2	2635	18	23.5	0.77	0.5–1.2
Total	96 156	730	712	1.0	1.0–1.1	32 202	80	106	0.8	0.6–0.9	15 936	145	140	1.04	0.9–1.2

ALL, acute lymphoblastic leukemia; AML, acute myeloid leukemia; CI, confidence interval; CLL, chronic lymphoblastic leukemia; CML, chronic myeloid leukemia; Exp.#, number of expected total joint arthroplasties in general population; n/a, not applicable; Obs.#, number of observed total joint arthroplasties in study group; Per. Years, observer person years; SIR, standardized incidence ratio.