Table 1.
Mean values of maximal isometric neck strength, mechanical properties of splenius capitis on the affected side, and TWSTRS scores at baseline and regular intervals following botulinum toxin injections in patients with cervical dystonia
| Baseline, mean (SD) | At 2 wk, mean (SD) | At 4 wk, mean (SD) | At 8 wk, mean (SD) | At 12 wk, mean (SD) | |
|---|---|---|---|---|---|
| Neck muscle strength | |||||
| Flexion (N) | 92.8 (45.2) | 76.7 (37.0)* | 83.2 (37.4) | 90.3 (48.0) | 90.1 (41.0) |
| Extension (N) | 179.4 (73.5) | 128.7 (74.8)* | 127.7 (68.9)* | 148.8 (79.3)* | 172.2 (79.0) |
| Rotation (Nm) | 10.6 (6.6) | 8.0 (5.4)* | 8.6 (5.5)* | 10.2 (7.3) | 10.1 (5.8) |
| Mechanical properties | |||||
| Tension (Hz) | 15.6 (3.1) | 14.5 (2.1) | 14.6 (2.5)* | 15.2 (1.2) | 15.4 (2.1) |
| Elasticity | 1.26 (0.18) | 1.34 (0.26) | 1.35 (0.19) | 1.41 (0.13)* | 1.39 (0.12) |
| Stiffness (N/m) | 319 (109) | 274 (93) | 265 (82)* | 278 (53) | 244 (32) |
| Compliance (mJ) | 22.1 (4.7) | 23.8 (4.8) | 24.3 (6.6) | 22.4 (3.1) | 21.7 (5.9) |
| TWSTRS | |||||
| Severity (0 to 35) | 12.4 (3.8) | 8.1 (4.3)* | 9.1 (4.0)* | 10.8 (3.0)* | 13.6 (3.0) |
| Disability (0 to 30) | 7.1 (3.9) | 6.0 (2.9) | 6.4 (2.4) | 7.1 (3.9) | 8.1 (2.9) |
| Pain (0 to 20) | 6.3 (4.1) | 5.3 (4.9) | 4.2 (3.4) | 5.3 (4.9) | 5.3 (4.8) |
| Total (0 to 85) | 25.8 (10.3) | 19.4 (9.1)* | 21.0 (5.7) | 23.1 (10.0) | 27.0 (8.4) |
*
significantly different from baseline (p < 0.05).
Hz: hertz, N: newton, m: meter, mJ: millijoule, TWSTRS: Toronto Western Spasmodic Torticollis Rating Scale, SD: standard deviation.