study of botulinum toxin and recovery of hand function after stroke

Conditions: Stroke With Hemiparesis

Summary: the purpose of this study is to determine whether injections of botulinum toxin (commonly known as botox®) into the affected hand of stroke patients, while targeting the muscles controlling the hand, will lead to improved use of the hand when compared to injections of placebo (a substance that looks similar to the study drug but contains no active study medication).

hemiparesis is the most common motor impairment after stroke that frequently leads to persistent deficits in hand function. this study investigates whether the application of botulinum toxin to a set of synergistically-acting hand muscles, in conjunction with task-specific therapy, will lead to reorganization and improved motor function in the stroke-involved hand. the investigators will use objective psychophysical measures of hand function and hand function rating scales to investigate if botox in conjunction with task-specific therapy will lead to: * improved motor execution, * improved motor planning during a psychophysical two-finger grasping and lifting task with varying object weight, and * increased hand function as assessed by the time taken to complete fine motor tasks.

Eligibility criteria:
inclusion criteria: * ability to follow study instructions and likely to complete all required visits * ability to comply with the therapy protocol as assessed by the investigator * 3 months post first-time unilateral stroke with right or left hemiparesis and complaints of unilateral hand dysfunction * must have ability to grasp and lift the test object * subjects must have upper extremity motor impairment exclusion criteria: * known allergy or sensitivity to botulinum toxin type a (botox). * females with a positive pregnancy test, or who are breast-feeding, planning a pregnancy during the study, who think that they may be pregnant at the start of the study or females of childbearing potential who are unable or unwilling to use a reliable form of contraception during the study. * concurrent participation in another investigational drug or device study or participation in another botulinum toxin study in the 6 months prior to study. * treatment with botulinum toxin of any serotype in the 3 months prior to study enrollment * any medical condition that may put the subject at increased risk with exposure to botox including diagnosed myasthenia gravis, eaton-lambert syndrome, amytrophic lateral sclerosis, or any other disorder that might interfere with neuromuscular function. * evidence of alcohol, drug abuse or other relevant neuropsychiatric condition. * infection or skin disorder at an anticipated injection site. * any condition or situation that, in the investigator's opinion, may put the subject at significant risk, confound the study results, or interfere significantly with the subject's participation in the study. * history of surgery or other significant injury to either upper extremity causing mechanical limitations that preclude task performance. * previous neurological illness such as head trauma, prior stroke, epilepsy, or demyelinating disease. * complicating medical problems such as uncontrolled hypertension, diabetes with signs of polyneuropathy, severe renal, cardiac or pulmonary disease, or evidence of other concurrent neurologic or orthopedic conditions precluding the subject from complying with the study protocol. * current treatment with intrathecal baclofen.

Keywords: rehabilitation fingers grasp hand strength brain infraction pathology physiopathology functional laterality neuronal plasticity psychomotor performance biomechanics touch weight-bearing