Background
Methods
Study population
Radiographic evaluation
Pain assessment
Statistical analyses
Regression to the mean
Results
Demographic characteristics placebo group, per protocol population | ||||
---|---|---|---|---|
Parameter | Target knee N = 771 | Non-target knee N = 256 | ||
Sex - n (%) | ||||
Male | 280 (36.3) | 82 (32.0) | ||
Female | 491 (63.7) | 174 (68.0) | ||
Age (years) | ||||
Mean (SD) | 64.5 (6.5) | 64.70 (6.3) | ||
Median (min, max) | 64.1 (50, 81) | 64.5 (50.4, 79.5) | ||
Age group (years) – n (%) | ||||
< 65 | 456 (59.1) | 137 (53.5) | ||
≥ 65 | 315 (40.9) | 119 (46.5) | ||
Race – n (%) | ||||
Caucasian | 666 (86.4) | 228 (89.1) | ||
Asian | 103 (13.4) | 27 (10.5) | ||
Other | 2 (0.3) | 1 (0.4) | ||
BMI (kg/m2) | ||||
Mean (SD) | 28.6 (4.7) | 28.6 (4.4) | ||
Median (min, max) | 27.9 (17.3, 45.9) | 28.1 (19.6, 43.3) | ||
KL Score - n (%) | ||||
KL 0 | N/A | 5 (2) | ||
KL 1 | N/A | 37 (14.5) | ||
KL 2 | 641 (83.1) | 130 (50.8) | ||
KL 3 | 130 (16.9) | 73 (28.5) | ||
KL4 | N/A | 10 (3.9) | ||
JSW (mm) | ||||
Mean (SD) | 3.43 (0.99) | 3.15 (1.56) | ||
Median (min, max) | 3.4 (1.8, 6.7) | 3.39 (0.0, 7.3) | ||
WOMAC pain score (normalized 0–100) | Mean (SD) | Median (min, max) | Mean (SD) | Median (min, max) |
Total pain (Q1–5) | 49 (15) | 47 (10, 100) | 50 (16) | 47 (30, 96) |
Walking on flat surface (Q1) | 47 (20) | 47 (2, 100) | 47 (21) | 46 (2, 99) |
Stairs (up or down) (Q2) | 65 (18) | 65 (2, 100) | 65 (19) | 63 (13, 100) |
In bed at night (Q3) | 42 (26) | 41 (0, 100) | 44 (24) | 44 (0, 98) |
Sitting or lying (Q4) | 42 (22) | 40 (0, 100) | 43 (22) | 43 (0, 100) |
Standing(Q5) | 49 (21) | 49 (0, 100) | 49 (20) | 48 (3, 100) |
Weight-bearing Composite (Q1, 2, 5) | 53 (15) | 52 (2, 100) | 53 (17) | 51 (18, 96) |
Non-weight-bearing Composite (Q3, Q4) | 42 (21) | 40 (0, 100) | 44 (21) | 41 (0–96) |
Pain categories and pain placebo reduction
WOMAC sub-score | SD | σ2b | σ2w | Estimated RTM effect from BL to Y2 (%) | Pain change from BL to Y2 adjusted for estimated RTM effect (%) |
---|---|---|---|---|---|
Question 1: Walking on flat surface | 56 | 1602.5 | 1533.5 | 32.6 | 0.9 |
Question 2: On stairs | 38 | 735.0 | 709.0 | 26.0 | −10.9 |
Question 3: Lying in bed | 80 | 3872.0 | 2528.0 | 33.7 | 11.2 |
Question 4: Sitting or lying | 69 | 2551.9 | 2209.1 | 35.6 | 6.3 |
Question 5: Standing | 57 | 1614.8 | 1634.3 | 33.9 | −0.1 |
Questions 1, 2, and 5: Weight-bearing | 39 | 734.6 | 786.4 | 27.8 | −15,4 |
Questions 3 and 4: Non-weight-bearing | 65 | 2433.6 | 1791.4 | 31.2 | −4.6 |
Baseline clinical and radiographic features and pain change in patients receiving placebo
Associations of baseline pain and radiographic joint-space narrowing
Target knee
Non-target knee
Variables | WOMAC Q1 | WOMAC Q2 | WOMAC Q3 | WOMAC Q4 | WOMAC Q5 | WOMAC Weight-bearing | WOMAC idle | Total WOMAC pain score | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
adj | unadj | adj | unadj | adj | unadj | adj | unadj | adj | unadj | adj | unadj | adj | unadj | adj | unadj | ||
Target chg in JSW yr. 2 | Spearman | −0.03 | − 0.01 |
− 0.10
|
−0.08
| − 0.05 | −0.03 | 0.00 | 0.00 | 0.04 | 0.05 | −0.04 | −0.02 | − 0.02 | −0.02 | − 0.04 | −0.02 |
P
| 0.40 | 0.70 |
0.006
|
0.03
| 0.27 | 0.36 | 0.98 | 0.90 | 0.29 | 0.15 | 0.31 | 0.59 | 0.54 | 0.62 | 0.33 | 0.60 | |
N | 771 | 771 |
771
|
771
| 771 | 771 | 771 | 771 | 771 | 771 | 771 | 771 | 771 | 771 | 771 | 771 | |
Non Target chg in JSW yr. 2 | Spearman | 0.07 |
0.09
| 0.06 |
0.09
| 0.01 | 0.03 | 0.06 |
0.07
|
0.08
|
0.10
|
0.08
|
0.10
| 0.04 | 0.05 |
0.07
|
0.09
|
P
| 0.07 |
0.02
| 0.09 |
0.02
| 0.71 | 0.40 | 0.10 |
0.05
|
0.02
|
0.007
|
0.03
|
0.007
| 0.27 | 0.14 |
0.05
|
0.01
| |
N | 733 |
733
| 733 |
733
| 733 | 733 | 733 |
742
|
733
|
742
|
733
|
739
| 733 | 733 |
733
|
733
|