Less periprosthetic bone loss following the anterolateral approach to the hip compared with the direct lateral approach

Figures & data

Table 1. Baseline characteristics of included patients according to allocated surgical approach (figures are numbers unless stated otherwise)

	Anterolateral (n = 26)	Lateral (n = 25)
Mean (SD) age	82 (5.5)	84 (6.2)
Female/Male	17/9	16/9
ASA group I, II/III, IV	10/16	6/19
BMI (SD)	23 (4.0)	23 (3.2)
Dorr type^a A, B/C	22/4	20/5
Median stem size (range)	12 (9–18)	12 (10–16)
Mean (SD) HHS^b	84 (19)	84 (18)

a Dorr classification.

b Harris hip score estimated prior to fall.

Figure 1. Hemiarthroplasty: Corail stem with bipolar head.

Figure 2. Flowchart of patients during the study.

Table 2. Precision of DXA measurements. Coefficients of variation (CV%)

Gruen zone:	1	2	3	4	5	6	7
CV%	3.2	2.4	2.1	1.2	3.8	5.5	4.7

Table 3. Periprosthetic changes in bone mineral density (BMD) around the hydroxyapatite-coated Corail stem measured by dual-energy X-ray absorptiometry (DXA)

Gruen	Surgical		Postoperative		3-months change		12-months change
zone	approach^a	n	mean BMD (CI)	n	% (CI)	n	% (CI)
1–7		51	1.61 (1.55–1.68)	43	4.2 (2.4–6.1)^b	38	5.8 (3.3–8.3)^b
1	AL	26	0.81 (0.74–0.88)	21	2.7 (–2.9–8.4)^b	18	–3.8 (–13–6.0)
	L	25	0.82 (0.76–0.89)	22	–5.0 (–10–0.5)	20	–7.4 (–15–0.3)
2	AL	26	1.79 (1.68–1.90)	21	4.1 (–2.8–11)^b	18	1.6 (–7.3–11)
	L	25	1.91 (1.80–2.03)	22	–4.3 (–7.6–0.9)	20	–6.6 (–9.9 to –3.4)
3	AL	26	2.08 (1.95–2.21)	21	–1.5 (–6.2–3.2)	18	–1.3 (–7.6–4.9)
	L	25	2.18 (2.05–2.31)	22	–4.9 (–8.0 to –1.8)	20	–6.1 (–8.5 to –3.8)
4	AL	26	1.84 (1.71–1.98)	21	–3.6 (–6.1 to –1.2)	18	–5.1 (–7.3 to –2.9)
	L	25	1.87 (1.73–2.00)	22	–5.4 (–6.9–3.9)	20	–7.0 (–8.8 to –5.3)
5	AL	26	2.18 (2.04–2.31)	21	–5.7 (–8.0 to –3.4)	18	–5.9 (–9.5 to –2.3)
	L	25	2.19 (2.05–2.34)	22	–8.0 (–11 to –4.6)	20	–6.1 (–9.1– to –3.2)
6	AL	26	1.50 (1.43–1.58)	21	0.0 (–4.6–4.6)^b	18	–1.9 (–8.9–5.1)^b
	L	25	1.50 (1.41–1.60)	22	–6.5 (–11 to –2.0)	20	–11 (–16 to –5.6)
7	AL	26	0.98 (0.88–1.08)	20^c	–2.4 (–7.6 –2.8)^b	18	–7.8 (–17– 0.9)
	L	25	0.97 (0.85–1.10)	22	–11 (–18 to –4.1)	20	–12 (–29–5.4)

The mean bone mineral density (g/cm²) postoperatively serves as baseline. Mean percentage change in BMD at 3 and 12 months (95% CI) for each Gruen zone and for the total periprosthetic region.

a AL = anterolateral; L = lateral.

b p < 0.05.

c One excluded due to the formation of heterotopic ossification.