3.1 Basic data comparison
As shown in Table 1, a total of 80 patients included in this study were divided into two groups according to surgical methods, with 40 patients in each group. In the PA group, 4 people lost their weight during the study. There were 22 men and 18 women in the DAA group, and 17 men and 19 women in the PA group. The average age in the DAA group was (63.02±4.53) years, the average age in the PA group was (62.58±4.17) years, the average height of patients in the DAA group was (1.67±0.08) m, and the average height of patients in the PA group was (1.68±0.07) m. The mean weight of patients in the DAA group was (63.29±7.80) kg, and the mean height of patients in the PA group was (64.50±6.73) kg. The BMI of patients in the DAA group was (22.77±1.77) kg/m2, and the BMI of patients in the PA group was (22.91±1.21) kg/m2. In the DAA group, 19 patients underwent surgery on the left lower limb and 21 patients underwent surgery on the right lower limb. In the PA group, 20 patients underwent surgery on the left lower limb and 16 patients underwent surgery on the right lower limb. There was no statistical difference between the two groups.
Table 1 Preoperative demographic analysis of patients
Group(mean±standard deviation)
|
Age
|
Height
|
Weight
|
BMI
|
Sex
|
Operative limb
|
Male
|
Female
|
Left
|
Right
|
DAA(n=40)
|
63.02±4.53
|
1.67±0.08
|
63.29±7.80
|
22.77±1.77
|
22
|
18
|
19
|
21
|
PA(n=36)
|
62.58±4.17
|
1.68±0.07
|
64.50±6.73
|
22.91±1.21
|
17
|
19
|
20
|
16
|
t
|
0.441
|
-0.593
|
-0.720
|
-0.429
|
X2=0.459
|
X2=0.492
|
p
|
0.661
|
0.555
|
0.474
|
0.669
|
0.498
|
0.483
|
* p<0.05 ** p<0.01
|
3.2 Comparison of preoperative bone mineral density and gait analysis indexes
The patients in this study underwent gait analysis and bone mineral density examination after admission, and their data were analyzed. The analysis results are shown in Table 2. step, stride, Percentage of gait cycle with single support phase of affected limb, pace, step frequency, hip in two groups extension, adduction degree of hip joint abduction, internal and external rotation of the hip joint, bone density in gruen1 There was no significant difference in bone density in gruen7 region (P< 0.05).
Table 2 Comparison of preoperative gait indexes and bone mineral density between direct anterior approach group and posterior approach group in total hip replacement (x±s)
Group(mean ± standard deviation)
|
DAA(n=40)
|
PA(n=36)
|
t
|
p
|
* p<0.05
** p<0.01
|
Preoperative step
|
35.38±2.33
|
35.83±2.46
|
-0.835
|
0.406
|
Preoperative stride
|
69.28±2.55
|
68.48±2.95
|
1.279
|
0.205
|
Percentage of gait cycle with single support phase of affected limb before operation
|
22.59±2.34
|
22.31±2.61
|
0.492
|
0.624
|
Preoperative pace
|
54.63±3.22
|
54.44±3.71
|
0.227
|
0.821
|
Preoperative step frequency
|
42.34±1.48
|
42.28±0.99
|
0.229
|
0.819
|
Preoperative hip extension
|
30.45±2.58
|
29.53±2.60
|
1.549
|
0.126
|
Preoperative adduction degree of hip joint abduction
|
7.15±0.33
|
7.17±0.23
|
-0.348
|
0.729
|
Preoperative internal and external rotation of the hip joint
|
10.03±0.69
|
9.71±0.77
|
1.897
|
0.062
|
Preoperative bone density in gruen1 region
|
0.68±0.04
|
0.67±0.04
|
1.709
|
0.092
|
Preoperative bone density in gruen7 region
|
0.59±0.21
|
0.59±0.23
|
-0.039
|
0.969
|
3.3 Comparison of bone mineral density and gait analysis indexes 1 week after operation
The gait analysis indexes and bone mineral density of the patients were reviewed one week after surgery. The average Step of the patients in the DAA group was (39.95±2.22) cm, and that of the PA group was (37.96±2.10) cm, with statistical difference between the two groups (P<0.05). The mean Stride of DAA group was (78.17±2.13) cm and that of PA group was (75.04±2.63) cm, and there was a statistical difference between the two groups (P<0.05). The mean value of Percentage of gait cycle with single brace phase in affected limb was 26.07±1.97% in DAA group and 24.42±2.38% in PA group, and there was statistical difference between the two groups (P< 0.05). The average Pace of the DAA group was 62.58±3.15cm/s, and the average pace of the PA group was 58.94± 2.94cm /s, and there were statistical differences between the two groups (P< 0.05). The mean hip extension of the DAA group was (35.83±1.72) degrees, and that of the PA group was (31.19±2.07) degrees, and there were statistically significant differences between the two groups (P< 0.05). The mean value of hip internal and external rotation was (12.41±0.41) degrees in the DAA group and (11.27±0.74) degrees in the PA group. There was no significant difference in hip internal and external rotation values between the two groups (P=0.160). The mean BMD in Gruen1 area was (0.67±0.04) g·cm-2 in DAA group and (0.66±0.04) g·cm-2 in PA group one week after
surgery, with no statistical difference between the two groups (P=0.422). The mean BMD in
Gruen7 area 1 week after surgery was (0.56±0.24) g·cm-2 in DAA group and (0.56±0.24)
g·cm-2 in PA group, with no statistical difference between the two groups (P=0.945).
Table 3 Comparison of gait indexes and bone mineral density between direct anterior approach group and posterior approach group in total hip replacement 1week after surgery (x±s)
Group(mean ± standard deviation)
|
DAA(n=40)
|
PA(n=36)
|
t
|
p
|
* p<0.05
** p<0.01
|
Step 1 week after surgery
|
39.95±2.22
|
37.96±2.10
|
4.009
|
0.000**
|
Stride length 1 week after surgery
|
78.17±2.13
|
75.04±2.63
|
5.723
|
0.000**
|
Percentage of gait cycle with single brace phase in affected limb 1 week after surgery
|
26.07±1.97
|
24.42±2.38
|
3.321
|
0.001**
|
Pace 1 week after surgery
|
62.58±3.15
|
58.94±2.94
|
5.184
|
0.000**
|
Step frequency 1 week after surgery
|
48.51±0.92
|
45.52±1.36
|
11.068
|
0.000**
|
Hip extension 1 week after surgery
|
35.83±1.72
|
31.19±2.07
|
10.643
|
0.000**
|
Internal and external rotation of the hip 1 week after surgery
|
12.41±0.41
|
11.27±0.74
|
8.182
|
0.000**
|
Hip adduction and abduction degree 1 week after surgery
|
7.45±0.31
|
7.35±0.28
|
1.420
|
0.160
|
Bone density in gruen1 zone 1 week after surgery
|
0.68±0.03
|
0.64±0.03
|
4.876
|
0.000**
|
Bone density in gruen7 zone 1 week after surgery
|
0.56±0.24
|
0.56±0.24
|
0.069
|
0.945
|
3.4 Comparison of bone mineral density and gait analysis indexes 1 month after operation
The patient’s gait indexes and bone mineral density were reviewed one month after surgery. After data analysis, as shown in Table 4, step, stride, Percentage of gait cycle with single support phase of affected limb, pace, step frequency, hip of DAA group extension, internal and external rotation of the hip joint, bone density in gruen1 region, bone density in gruen7 region values were all higher than those in PA group, except bone density in gruen7 region (P=0.581), which had statistical significance (P<0.05). The adduction degree of hip joint abduction in the DAA group was lower than that in the PA group, and the values of the two groups were statistically significant (P<0.05).
Table 4 Comparison of gait indexes and bone mineral density between direct anterior approach group and posterior approach group in total hip replacement 1 month after surgery (x±s)
Group(mean ± standard deviation)
|
DAA(n=40)
|
PA(n=36)
|
t
|
p
|
* p<0.05
** p<0.01
|
Step 1 month after surgery
|
46.67±2.62
|
42.28±2.68
|
7.213
|
0.000**
|
Stride length 1 month after surgery
|
87.42±2.28
|
83.56±2.47
|
7.071
|
0.000**
|
Percentage of gait cycle with single brace phase in affected limb 1 month after surgery
|
33.33±2.71
|
30.72±2.41
|
4.403
|
0.000**
|
Pace 1 month after surgery
|
71.92±4.23
|
65.78±3.39
|
6.943
|
0.000**
|
Step frequency 1 month after surgery
|
58.41±1.00
|
47.33±0.84
|
51.897
|
0.000**
|
Hip extension 1 month after surgery
|
39.80±2.81
|
34.44±2.31
|
9.011
|
0.000**
|
Internal and external rotation of the hip 1 month after surgery
|
15.17±0.92
|
13.63±0.34
|
9.839
|
0.000**
|
Hip adduction and abduction degree 1 month after surgery
|
9.60±0.75
|
10.62±0.26
|
-8.071
|
0.000**
|
Bone density in gruen1 zone 1 month after surgery
|
0.75±0.03
|
0.73±0.04
|
2.857
|
0.006**
|
Bone density in gruen7 zone 1 month after surgery
|
0.63±0.23
|
0.60±0.22
|
0.554
|
0.581
|
3.5 Comparison of bone mineral density and gait analysis indexes 3 months after operation
The patient’s gait indexes and bone mineral density were reviewed 3 months after surgery. After data analysis, as shown in Table 5, step, stride, Percentage of gait cycle with single support phase of affected limb, pace, step frequency, hip of DAA group extension, internal and external rotation of the hip joint, bone density in gruen1 region, bone density in gruen7 region values were better than those in PA group one month after operation, and were all higher than those in PA group(P< 0.05), with statistical significance except bone density in gruen7 region (P=0.259). The adduction degree of hip joint abduction in the DAA group was lower than that in the PA group, and the values of the two groups were statistically significant (P<0.05).
Table 5 Comparison of gait indexes and bone mineral density between direct anterior approach group and posterior approach group in total hip replacement 3 month after surgery (x±s)
Group(mean ± standard deviation)
|
DAA(n=40)
|
PA(n=36)
|
t
|
p
|
* p<0.05
** p<0.01
|
Step 3 month after surgery
|
54.46±2.36
|
51.23±2.39
|
5.929
|
0.000**
|
Stride length 3 month after surgery
|
99.44±2.77
|
91.64±2.54
|
12.730
|
0.000**
|
Percentage of gait cycle with single brace phase in affected limb 3 month after surgery
|
37.48±3.34
|
35.31±2.62
|
3.125
|
0.003**
|
Pace 3 month after surgery
|
101.63±3.79
|
94.08±3.43
|
9.048
|
0.000**
|
Step frequency 3 month after surgery
|
60.65±1.50
|
59.77±0.75
|
3.283
|
0.002**
|
Hip extension 3 month after surgery
|
44.63±2.74
|
37.72±1.97
|
12.485
|
0.000**
|
Internal and external rotation of the hip 3 month after surgery
|
15.33±0.41
|
14.09±0.59
|
10.476
|
0.000**
|
Hip adduction and abduction degree 3 month after surgery
|
10.65±0.45
|
12.59±0.32
|
-21.557
|
0.000**
|
Bone density in gruen1 zone 3 month after surgery
|
0.76±0.05
|
0.74±0.03
|
2.308
|
0.024*
|
Bone density in gruen7 zone 3 month after surgery
|
0.78±0.24
|
0.71±0.25
|
1.137
|
0.259
|
3.6 Correlation analysis between gait data and bone mineral density
There was a positive correlation between gait indexes and BMD at 1 month and 3 months in the direct anterior approach group and the posterior approach group (R> 0 ,P< 0.05), as shown in FIG. 3-10. Bone mineral density in gruen1 area was significantly correlated with hip flexion and extension in the PA group one month after surgery (R2=0.1506, P=0.0531).