Mechanisms of Upper-Extremity Motor Recovery in Post-stroke Hemiparesis
Mechanisms of Upper-Extremity Motor Recovery in Post-stroke Hemiparesis
The results of this study will provide sound, scientific evidence of physiologic mechanisms
 responsible for upper-extremity weakness; evidence of the processes involved in neuromuscular
 adaptation; and will elucidate the relationship between impairment and motor disability in
 post-stroke hemiparesis.
This proposal extends the work accomplished in our initial study (project #B2405R, 'Effects
 of Strength Training on Upper-limb Function in Post-stroke Hemiparesis'). In the present
 study we will conduct a double-blind, randomized clinical trial of staged rehabilitation for
 the upper-extremity involving sequential delivery of functional therapy and high intensity
 resistance training. Therefore, this proposal directly compares the effects of functional and
 resistance training delivered individually. The researchers' previous work investigated a
 hybrid therapy of functional and resistance training against functional training alone. All
 subjects will participate in a 5 week run-in period of no treatment. This no-treatment block
 will afford multiple baseline measurements and, in addition, will provide information
 regarding the rate and magnitude of any spontaneous recovery without treatment. Following the
 second baseline measurement, all subjects will be randomized to upper-extremity
 rehabilitation in either: Order A - 10 weeks of functional task practice training (FTP)
 followed by 10 weeks of high-intensity resistance training (Power) or Order B - resistance
 training (Power) followed by FTP. Re-evaluation will occur following each block of
 treatment,and retention effects will be evaluated after 6 and 12 months with no additional
 treatment. Subjects will be evaluated with: outcome measures used broadly in Clinical
 Neurology and Rehabilitation, a battery of biomechanical performance measures including:
 strength, muscle activation, reflex modulation, and motor coordination, and with kinematics
 of free reaching movements. The researchers will investigate persons in the intermediate
 phase of recovery which they define as between 6 and 18 months post-stroke , having completed
 all inpatient and outpatient therapies, with remaining residual motor deficits.
Inclusion Criteria:

 -  Clinical diagnosis of cerebrovascular accident

 -  Single event

 -  Unilateral hemiplegia

 -  Between 6 months and 18 months post-event

 -  Impairment of upper-extremity function

 -  Ability to produce partial range of motion out of plane of gravity at shoulder, elbow,
 and wrist

 -  At least 10 degrees of wrist motion (any 10 degrees), and finger flexion/extension in
 2 fingers

 -  Cognitive ability to follow 3-step commands

 Exclusion Criteria:

 -  Unstable or uncontrolled blood pressure

 -  Uncontrolled seizures

 -  Flaccid hemiplegia

 -  Severe cognitive impairment