The posterior approach reduces the risk of thin cement mantles with a straight femoral stem design

Figures & data

Table 1.  Demographic data of study group

	Anterolateral approach (n = 135)	Posterior approach (n = 135)
Patients (bilateral)	115 (20)	122 (13)
Mean age (range)	67 (31–90)	68 (46–82)
Male/female	38/97	51/84
Left/right	68/67	68/67
Diagnosis
OA	120 (89%)	114 (85%)
RA	0	2 (2%)
Post-traumatic OA	2 (2%)	3 (2%)
DDH	7 (5%)	10 (8%)
Other	6 (5%)	6 (5%)
BMI (range)	29 (17–34)	28 (21–32)

BMI only available for 204 patients: 101 patients in the antero-lateral group, 103 patients in the posterior group.

Table 2.  Cement mantle integrity according to Barrack

Barrack classification	Antero-lateral n (%)	Posterior n (%)
A	40 (30)	44 (33)
B	93 (69)	84 (62)
C	2 (2)	7 (5)
D	0	0

Table 3.  Stem alignment on AP radiograph

Alignment	Antero-lateral n (%)	Posterior n (%)
Neutral	121 (90)	111 (82)
Varus	7 (5)	21 (16)
Valgus	7 (5)	3 (3)

Table 4.  Stem alignment on lateral radiograph

Alignment	Antero-lateral n (%)	Posterior n (%)
Neutral	104 (77)	102 (76)
Anterior	5 (4)	19 (14)
Posterior	26 (19)	14 (10)

Table 5.  Cement mantle thickness on AP and lateral radiographs. Values are percentage with antero-lateral/posterior approach

Gruen zone
	1	2	3	4	5	6	7	8	9	10	11	12	13	14
≥ 2 mm	98/99	98/99	98/99	98/99	97/97	96/95	99/99	68/79	72/81	99/99	99/99	97/97	100/100	99/99
< 2 mm	2/1	2/1	2/1	0/0	2/2	3/3	1/1	27/19	26/15	1/1	0/0	2/3	0/0	1/1
< 1 mm	0/0	0/0	0/0	2/1	1/1	1/2	0/0	5/2	2/4	0/0	1/1	1/0	0/0	0/0