Additional outcomes comparing the IA-BoNT/A and IA-placebo groups using generalized estimating equations (GEE) analyses. Data are mean (SD).
| Baseline Preinjection | 2 Weeks | 1 Month | 2 Months | 3 Months | 4 Months | p (repeated measures analyses*†) | |
|---|---|---|---|---|---|---|---|
| Mean VAS pain (0–10) | 0.09 | ||||||
| IA-BoNT/A | 7.2 (1.1) | NA | NA | 4.4 (2.5) | 4.2 (2.6) | 4.8 (2.4) | |
| IA-placebo | 7.5 (1.3) | NA | NA | 5.7 (2.9) | 5.2 (3.2) | 5.0 (2.6) | |
| Secondary outcomes | |||||||
| WOMAC physical function (0–100) | |||||||
| IA-BoNT/A | 56.5 (8.9) | 48.3 (13.1) | 47.8 (14.7) | 48.5 (14.4) | 46.8 (16.6) | 45.9 (17.9) | 0.03 |
| IA-placebo | 63.3 (17.5) | 60.9 (16.0) | 57.7 (18.8) | 59.7 (17.4) | 52.9 (21.1) | 57.1 (17.4) | |
| WOMAC stiffness (0–100) | |||||||
| IA-BoNT/A | 64.1 (20.4) | 44.3 (24.9) | 49.4 (20.9) | 51.8 (19.1) | 50.0 (19.7) | 47.4 (25.5) | < 0.01 |
| IA-placebo | 64.4 (18.9) | 63.7 (18.1) | 48.9 (26.1) | 60.4 (16.3) | 57.7 (23.5) | 59.9 (22.7) | |
| WOMAC pain (0–100) | |||||||
| IA-BoNT/A | 58.0 (13.6) | 40.0 (16.9) | 49.5 (18.1) | 45.2 (22.3) | 43.6 (20.1) | 42.6 (20.1) | 0.12 |
| IA-placebo | 67.1 (15.3) | 54.7 (19.7) | 57.0 (17.6) | 58.3 (14.7) | 51.2 (22.7) | 51.6 (20.9) | |
| WOMAC total (0–100) | |||||||
| IA-BoNT/A | 63.2 (9.3) | 50.9 (15.2) | 53.1 (16.2) | 52.9 (15.5) | 51.0 (17.8) | 49.9 (18.3) | 0.02 |
| IA-placebo | 70.6 (16.8) | 65.9 (17.7) | 62.5 (19.1) | 65.5 (17.0) | 58.3 (22.3) | 61.8 (18.9) | |
| Timed Stands Test | |||||||
| IA-BoNT/A | 49.9 (31.4) | NA | NA | 37.4 (15.8) | 35.5 (13.9) | 37.6 (15.7) | 0.98 |
| IA-placebo | 50.8 (29.3) | NA | NA | 42.1 (22.5) | 39.3 (22.1) | 38.9 (13.0) | |
| Timed Up and Go Test | |||||||
| IA-BoNT/A | 18.3 (13.8) | NA | NA | 17.2 (9.6) | 17.6 (13.2) | 14.8 (5.9) | 0.14 |
| IA-placebo | 18.5 (12.7) | NA | NA | 18.2 (13.8) | 15.5 (10.5) | 18.2 (16.3) | |
| Active flexion | |||||||
| IA-BoNT/A | 83.3 (22.5) | NA | NA | 75.0 (20.8) | 74.7 (23.0) | 79.3 (23.0) | 0.23 |
| IA-placebo | 86.2 (16.7) | NA | NA | 87.5 (15.3) | 85.6 (12.5) | 83.1 (15.4) | |
| Active extension | |||||||
| IA-BoNT/A | 170.7 (10.9) | NA | NA | 170.0 (18.0) | 169.7 (13.1) | 157.8 (44.4) | 0.86 |
| IA-placebo | 167.8 (10.0) | NA | NA | 170.5 (7.4) | 163.2 (40.2) | 163.7 (38.0) | |
| McGill affective dimension | |||||||
| IA-BoNT/A | 6.1 (2.8) | NA | 4.5 (3.1) | 3.8 (3.1) | 3.6 (3.1) | 3.9 (3.1) | 0.08 |
| IA-placebo | 5.3 (3.1) | NA | 4.1 (3.5) | 4.8 (3.4) | 4.8 (3.5) | 4.8 (3.3) | |
| McGill sensory dimension | |||||||
| IA-BoNT/A | 16.7 (6.5) | NA | 14.5 (8.3) | 14.5 (8.0) | 11.6 (6.3) | 12.9 (8.1) | 0.73 |
| IA-placebo | 17.3 (6.8) | NA | 13.4 (5.8) | 14.6 (7.5) | 11.7 (7.3) | 13.5 (8.4) | |
| McGill total | |||||||
| IA-BoNT/A | 23.8 (8.3) | NA | 19.0 (10.8) | 18.3 (10.1) | 15.4 (8.1) | 16.8 (10.8) | 0.42 |
| IA-placebo | 22.7 (8.8) | NA | 17.5 (8.4) | 19.4 (10.3) | 16.7 (9.8) | 18.3 (11.2) | |
| SF-36 subscales | |||||||
| Bodily pain†† | |||||||
| IA-BoNT/A | 28.5 (17.0) | NA | NA | 46.5 (19.0) | 42.9 (20.1) | 43.9 (22.7) | 0.049 |
| IA-placebo | 29.0 (13.7) | NA | NA | 36.4 (17.4) | 37.0 (23.3) | 39.1 (24.5) | |
| Physical functioning | |||||||
| IA-BoNT/A | 29.4 (21.3) | NA | NA | 30.7 (21.8) | 29.3 (15.1) | 30.5 (19.6) | 0.68 |
| IA-placebo | 20.6 (16.0) | NA | NA | 23.6 (17.5) | 25.2 (20.0) | 22.6 (18.8) | |
| Role physical | |||||||
| IA-BoNT/A | 12.0 (21.1) | NA | NA | 22.7 (29.8) | 26.1 (34.0) | 26.3 (30.9) | 0.74 |
| IA-placebo | 13.5 (23.7) | NA | NA | 18.0 (26.5) | 28.1 (32.4) | 29.8 (35.0) | |
| Role emotional | |||||||
| IA-BoNT/A | 49.3 (47.0) | NA | NA | 45.4 (40.6) | 56.1 (47.6) | 46.7 (43.8) | 0.08 |
| IA-placebo | 48.7 (49.2) | NA | NA | 61.3 (45.8) | 68.1 (42.3) | 63.5 (43.3) | |
| Mental health | |||||||
| IA-BoNT/A | 69.6 (17.1) | NA | NA | 67.8 (21.4) | 68.6 (17.8) | 68.6 (20.9) | 0.31 |
| IA-placebo | 64.0 (20.3) | NA | NA | 67.5 (21.7) | 70.7 (26.1) | 69.5 (20.1) | |
| Social functioning | |||||||
| IA-BoNT/A | 55.4 (26.1) | NA | NA | 64.8 (26.3) | 60.2 (26.9) | 60.6 (25.1) | 0.99 |
| IA-placebo | 50.5 (29.3) | NA | NA | 61.5 (27.7) | 62.0 (31.8) | 58.9 (37.3) | |
| General health | |||||||
| IA-BoNT/A | 52.9 (20.7) | NA | NA | 55.0 (20.4) | 49.3 (20.4) | 49.5 (24.4) | 0.98 |
| IA-placebo | 55.1 (24.4) | NA | NA | 51.8 (21.7) | 52.1 (21.6) | 53.2 (21.7) | |
| Vitality | |||||||
| IA-BoNT/A | 42.6 (17.8) | NA | NA | 41.6 (19.5) | 46.4 (15.6) | 45.0 (23.5) | 0.98 |
| IA-placebo | 40.0 (24.6) | NA | NA | 41.2 (24.3) | 44.4 (28.9) | 43.6 (27.9) | |
↵* Comparison of IA-BoNT/A and placebo for all efficacy timepoints up to 4 months using GEE, adjusting for respective baseline scores.
↵† Sensitivity analyses that included bilateral total knee arthroplasty (TKA) did not change the significance for any variable listed above (data not shown), except SF-36 pain, for which p value was 0.14 when all 60 TKA were included.
↵†† Only the SF-36 bodily pain subscale score was significantly different between groups; no other SF-36 subscale scores were significantly different between groups at 2 months. WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; SF-36: Short-form 36; NA: not applicable since these variables were not assessed at these telephone followup visits.