Measurement of involuntary muscle contraction in adults with spasticity

This study is looking at abnormal muscle co-contraction — where muscles that are supposed to relax actually tighten at the wrong time — in adults with upper motor neuron (UMN) syndrome. This occurs in conditions like stroke, traumatic brain injury, or multiple sclerosis, where damage to the nervous system leads to spasticity. Co-contraction can make everyday tasks like grasping objects very difficult, but it is poorly understood and hard to measure objectively. Researchers will use specialised equipment to measure muscle activity during a grasping and releasing task before and after participants receive Botulinum Toxin-A (Botox) injections, which are commonly used to treat spasticity. The goal is to better understand how co-contraction affects hand function and whether the injections change these patterns. You may be eligible if you are an adult with spasticity from a neurological condition lasting more than three months, mainly affecting one side, and you are already receiving Botulinum Toxin-A injections as part of your regular clinical care. A healthy control group (adults without neurological conditions) is also being recruited for comparison. People with other causes of upper limb weakness or who have contraindications to Botulinum Toxin-A are not eligible.