The mean patient age at the time of operation was 80.3 ± 6.3 years. The mean BMI was 20.8 ± 2.5 kg/m2. The HHS and EQ-5D-5L were 82.3 ± 15.8 and 0.78 ± 0.19 points, respectively. There were 6, 24, and 10 patients in the Dorr type A, B, and C groups, respectively. Table 1 shows patient backgrounds as assessed using the Dorr classification.
At 12 months, there was a significant difference in the BMD change rate at zone 2 between the Dorr B and C groups. The BMD change rate was significantly lower in the Dorr C than in the Dorr B group (p=0.036). There were no significant differences in any zone between the Dorr A and B groups and between the Dorr A and C groups. There was no significant difference between the three groups (Dorr A, B, C groups) in terms of HHS and EQ-5D-5L (Table 1).
Table 1. Patient demographics assessed using the Dorr classification and relationship between the Dorr classification and the BMD change rate.
|
Dorr A
|
Dorr B
|
Dorr C
|
p-value
|
Number of patients
|
6
(3 men, 3 women)
|
24
(8 men, 16 women)
|
10
(1 man, 9 women)
|
0.204
|
Age (years)
|
81.8 ± 4.5
|
80.0 ± 6.6
|
80.1 ± 7.3
|
0.173
|
BMI (kg/m2)
|
21.9 ± 3.1
|
20.8 ± 2.7
|
19.9 ± 1.8
|
0.338
|
HHS (points)
|
93.5 ± 6.0
|
81.9 ± 15.6
|
75.9 ± 19.0
|
0.087
|
EQ-5D-5L (score)
|
0.88 ± 0.11
|
0.76 ± 0.21
|
0.75 ± 0.18
|
0.287
|
Zone area
|
time
|
BMD change rate
|
|
Zone 1
|
6 m
|
0.90 ± 0.09
|
0.89 ± 0.11
|
0.88 ± 0.12
|
0.218
|
|
12 m
|
0.86 ± 0.12
|
0.86 ± 0.15
|
0.85 ± 0.13
|
0.943
|
Zone 2
|
6 m
|
0.91 ± 0.05
|
0.90 ± 0.12
|
0.83 ± 0.15
|
0.200
|
|
12 m
|
0.88 ± 0.07
|
0.88 ± 0.16*
|
0.77 ± 0.09*
|
0.036*
|
Zone 3
|
6 m
|
0.98 ± 0.03
|
0.96 ± 0.06
|
0.96 ± 0.09
|
0.673
|
|
12 m
|
0.96 ± 0.02
|
0.95 ± 0.08
|
0.97 ± 0.07
|
0.771
|
Zone 4
|
6 m
|
0.99 ± 0.02
|
0.98 ± 0.05
|
0.97 ± 0.05
|
0.769
|
|
12 m
|
0.98 ± 0.02
|
0.97 ± 0.05
|
0.97 ± 0.06
|
0.985
|
Zone 5
|
6 m
|
0.98 ± 0.03
|
0.97 ± 0.08
|
0.97 ± 0.08
|
0.948
|
|
12 m
|
0.96 ± 0.03
|
0.92 ± 0.21
|
0.98 ± 0.09
|
0.429
|
Zone 6
|
6 m
|
0.91 ± 0.08
|
0.91 ± 0.12
|
0.88 ± 0.15
|
0.911
|
|
12 m
|
0.90 ± 0.13
|
0.94 ± 0.10
|
0.82 ± 0.15
|
0.169
|
Zone 7
|
6 m
|
0.86 ± 0.15
|
0.78 ± 0.13
|
0.71 ± 0.16
|
0.298
|
|
12 m
|
0.86 ± 0.21
|
0.80 ± 0.16
|
0.67 ± 0.10
|
0.113
|
*p<0.05
Abbreviations: BMD: Bone Mineral Density, BMI: Body Mass Index, HHS: Harris Hip Score, EQ-5D-5L: EuroQol 5 dimensions 5 level
Regarding osteoporosis treatment, there were 6, 19, and 15 patients in the pre-injury intervention, post-injury intervention, and no-intervention groups, respectively. There was no significant difference between the three groups in age, BMI, HHS, and EQ-5D-5L. Regarding the relationship between the osteoporosis treatment intervention and BMD, there was a significant difference at 12 months in zones 1, 6, and 7 between the pre-injury intervention and no-intervention groups. The decline in the BMD change rate was significantly suppressed in the pre-injury intervention group compared to the no-intervention group (between-group comparison at 12 months in zone 1: p=0.039, at 6 months in zone 7: p=0.005, and at 12 months in zone 7: p=0.029). Moreover, at 6 and 12 months in zone 7, there was a significant difference between the pre-injury and post-injury intervention groups. The decline in the BMD change rate was significantly suppressed in the pre-injury intervention group than that in the post-injury intervention group (between-group comparison at 6 months in zone 7: p=0.003 and at 12 months in zone 7: p=0.004). However, there was no significant difference in the BMD change rate between the post-injury intervention and no-intervention groups (Table 2).
Table 2. Patient background classified based on osteoporosis therapy intervention and relationship between osteoporosis treatment intervention and the BMD change rate.
|
Pre-injury intervention
|
Post-injury intervention
|
No intervention
|
p-value
|
Number of patients
|
6
(Dorr A, 2; B, 3; C, 1) (1 man, 5 women)
|
19
(Dorr A, 1; B, 13; C, 5) (6 men, 13 women)
|
15
(Dorr A, 3; B, 8; C, 4) (5 men, 10 women)
|
0.523
0.737
|
Age (years)
|
84.2 ± 3.3
|
79.9 ± 6.8
|
79.2 ± 6.6
|
0.129
|
BMI (kg/m2)
|
21.1 ± 2.1
|
21.5 ± 2.7
|
19.7 ± 2.3
|
0.902
|
HHS (points)
|
83.7 ± 16.3
|
79.6 ± 18.3
|
85.2 ± 12.9
|
0.832
|
EQ-5D-5L (score)
|
0.82 ± 0.18
|
0.77 ± 0.22
|
0.77 ± 0.16
|
0.743
|
Zone area
|
time
|
BMD change rate
|
|
Zone 1
|
6 m
|
0.94 ± 0.10
|
0.86 ± 0.11
|
0.87 ± 0.11
|
0.351
|
|
12 m
|
0.95 ± 0.11+
|
0.88 ± 0.13
|
0.80 ± 0.14+
|
0.039+
|
Zone 2
|
6 m
|
0.93 ± 0.08
|
0.86 ± 0.16
|
0.89 ± 0.07
|
0.699
|
|
12 m
|
0.92 ± 0.09
|
0.86 ± 0.18
|
0.83 ± 0.10
|
0.357
|
Zone 3
|
6 m
|
1.01 ± 0.04
|
0.95 ± 0.06
|
0.97 ± 0.06
|
0.920
|
|
12 m
|
0.98 ± 0.03
|
0.96 ± 0.09
|
0.94 ± 0.05
|
0.336
|
Zone 4
|
6 m
|
1.00 ± 0.04
|
0.97 ± 0.04
|
0.98 ± 0.05
|
0.446
|
|
12 m
|
0.99 ± 0.02
|
0.97 ± 0.05
|
0.97 ± 0.04
|
0.552
|
Zone 5
|
6 m
|
0.98 ± 0.08
|
0.97 ± 0.07
|
0.96 ± 0.08
|
0.974
|
|
12 m
|
0.97 ± 0.04
|
0.96 ± 0.08
|
0.89 ± 0.26
|
0.700
|
Zone 6
|
6 m
|
0.98 ± 0.10
|
0.90 ± 0.13
|
0.87 ± 0.10
|
0.076
|
|
12 m
|
0.94 ± 0.10
|
0.92 ± 0.15
|
0.89 ± 0.09
|
0.387
|
Zone 7
|
6 m
|
0.94 ± 0.09 #+
|
0.73 ± 0.14#
|
0.76 ± 0.12+
|
0.003#, 0.005+
|
|
12 m
|
0.93 ± 0.11#+
|
0.74 ± 0.19#
|
0.78 ± 0.14+
|
0.004#, 0.029+
|
+p<0.05, #p<0.05
Abbreviations: BMD: Bone Mineral Density, BMI: Body Mass Index, HHS: Harris Hip Score, EQ-5D-5L: EuroQol 5 dimensions 5 level
Table 3 shows the type of anti-osteoporotic drugs administered. Vitamin D and bisphosphonate preparations were frequently used, and these two drugs accounted for more than 80% of the total. There were no peri-implant fractures, obvious stem subsidence, or major complications during the follow-up period in the 40 patients analysed.
Table 3. Type and number of anti-osteoporotic drug
Type of drug
|
Number of patients (n=39)
|
Vitamin D
|
17 (44%)
|
Bisphosphonate
|
16 (41%)
|
Denosumab
|
3 (8%)
|
Teriparatide
|
2 (5%)
|
SERM
|
1 (2%)
|
Abbreviation: SERM: selective oestrogen receptor modulator