ABSTRACT
Upper extremity (UE) hemiparesis persists after stroke, limiting hand function. Neuromuscular electrical stimulation (NMES) is an effective intervention to improve UE recovery, although the underlying mechanisms are not fully understood. Our objective was to establish a reliable protocol to measure UE agonist-antagonist forearm monosynaptic reflexes in a pilot study to determine if NMES improves wrist function after stroke. We established the between-day reliability of the H-reflex in the extensor carpi radialis longus (ECRL) and flexor carpi radialis (FCR) musculature for individuals with prior stroke (n=18). The same-day generation of ECRL/FCR H-reflex recruitment curves was well tolerated, regardless of age or UE spasticity. The between-day reliability of the ECRL H-reflex was enhanced above FCR, similar to healthy subjects [20], with the Hmax the most reliable parameter quantified in both muscles. H-reflex and functional measures following NMES show the potential for NMES-induced increases in ECRL Hmax, but confirmation requires a larger clinical study. Our initial results support the safe, easy, and efficacious use of in-home NMES, and establish a potential method to measure UE monosynaptic reflexes after stroke.
Subject(s)
Forearm/physiopathology , H-Reflex , Stroke/physiopathology , Transcutaneous Electric Nerve Stimulation , Adult , Aged , Aged, 80 and over , Clinical Protocols , Female , Humans , Male , Middle Aged , Paresis/etiology , Paresis/physiopathology , Paresis/rehabilitation , Pilot Projects , Stroke/complications , Stroke RehabilitationABSTRACT
The authors report two families with a myopathy phenotype affecting only women, marked by asymmetric weakness, skeletal asymmetry, and an elevated hemidiaphragm. One family had a mutation in a stop codon in exon 9 of the myotubularin gene, and the other had a splice site mutation in exon 13. Both families had manifesting and nonmanifesting carriers. Skewed X-inactivation appeared to explain the clinical manifestations in only one of the two families.
Subject(s)
Bone and Bones/abnormalities , Diaphragm/physiopathology , Muscular Diseases/complications , Muscular Diseases/genetics , Mutation/genetics , Protein Tyrosine Phosphatases/genetics , Adult , Child, Preschool , DNA Mutational Analysis , Diaphragm/pathology , Female , Functional Laterality/genetics , Genetic Predisposition to Disease/genetics , Genetic Testing , Heterozygote , Humans , Infant, Newborn , Inheritance Patterns/genetics , Male , Middle Aged , Muscle Weakness/genetics , Muscle Weakness/pathology , Muscle Weakness/physiopathology , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Muscle, Skeletal/physiopathology , Muscular Diseases/physiopathology , Pedigree , Phenotype , Protein Tyrosine Phosphatases, Non-Receptor , X Chromosome Inactivation/geneticsABSTRACT
OBJECTIVE: To characterize leg muscle abnormalities in patients with ALS using MRI, and to correlate MRI with standard neurologic measures of motor neuron dysfunction. METHODS: Eleven ALS patients were studied twice (once at baseline and again after 4 months) and compared with eight normal control subjects. MRI data of the lower extremities were compared with tibialis anterior compound muscle action potential amplitude (CMAPa) and foot dorsiflexion maximal voluntary isometric contraction (MVIC). RESULTS: Muscle MRI was abnormal by visual inspection in six of 11 patients. The mean muscle T1 time and muscle volume were not different in patients compared with normal control subjects (p > 0.1). However, the mean T2 times were increased in the patients compared with normal control subjects (p = 0.009). T1 times did not correlate with CMAPa or MVIC. Muscle volume correlated with MVIC (r = 0.73 to 0.78, p < 0.02) but not with CMAPa (p > 0.05). There was a strong negative correlation (r < -0.8, p < or = 0.01) between muscle T2 time and MVIC and CMAPa. Also, the change in T2 relaxation time correlated with the change in CMAPa as the disease progressed (r = -0.63, p = 0.037). CONCLUSION: Of the MRI characteristics studied, T2 relaxation time was the best indicator of motor neuron dysfunction and may have a role in objective evaluation of motor neuron dysfunction.
