Comparison Chart of Principal Differentiating Diagnostic Features
| . | Spasticity . | Dystonia . | Rigidity . |
|---|---|---|---|
| Summary | Velocity-dependent resistance | Sustained or intermittent muscle contractions | Independent of both speed and posture |
| Effect of increasing speed of passive movement on resistance | Increases | No effect | No effect |
| Effect of rapid reversal of direction on resistance | Delayed | Immediate | Immediate |
| Presence of a fixed posture | Only in severe cases | Yes | No |
| Effect of voluntary activity on pattern of activated muscles | Minimal | Yes | Minimal |
| Effect of behavioral task and emotional state on pattern of activated muscles | Minimal | Yes | Minimal |
| . | Spasticity . | Dystonia . | Rigidity . |
|---|---|---|---|
| Summary | Velocity-dependent resistance | Sustained or intermittent muscle contractions | Independent of both speed and posture |
| Effect of increasing speed of passive movement on resistance | Increases | No effect | No effect |
| Effect of rapid reversal of direction on resistance | Delayed | Immediate | Immediate |
| Presence of a fixed posture | Only in severe cases | Yes | No |
| Effect of voluntary activity on pattern of activated muscles | Minimal | Yes | Minimal |
| Effect of behavioral task and emotional state on pattern of activated muscles | Minimal | Yes | Minimal |
Reproduced with permission from: Sanger TD, Delgado MR, Gaebler-Spira D, Hallett M, Mink JW. Classification and definition of disorders causing hypertonia in childhood. Pediatrics. 2003;111(1):e89–e97.