Author Correction: The experience of spasticity after spinal cord injury: perceived characteristics and impact on daily life.

There is an author correction associated with this article.

The experience of spasticity after spinal cord injury: perceived characteristics and impact on daily life.

STUDY DESIGN: Cross-sectional survey. OBJECTIVES: Determine the impact of motor control characteristics attributed to spasticity, such as spasms, stiffness, and clonus on the daily life of people with spinal cord injury (SCI). SETTING: Nationwide, United States. METHODS: Internet-administered questionnaire, the Patient Reported Impact of Spasticity Measure (PRISM) and items describing characteristics of spasticity including stiffness, spasms, clonus, and pain. RESULTS: Of the 145 respondents, 113 (78%) reported a PRISM score of at least 5/164, indicating spasticity had some impact on their daily lives. Stiffness impact was highly correlated (ρ = 0.84; p < 0.01) with the PRISM negative impact on Daily Activities subscale and moderately correlated with the other PRISM subscales (ρ = 0.55-0.63; p < 0.01). Spasm presence had a negligible or low correlation with PRISM negative impact subscales (ρ = 0.29-0.47; p < 0.01). Trunk muscle stiffness and spasms had a low correlation with PRISM Need for Assistance and Daily activities (ρ = 0.42 and ρ = 0.41, p < 0.01, respectively). Anti-spasticity medications were ineffective for 58% of respondents. Pain in the legs was reported by 57% of respondents. CONCLUSIONS: The experience of spasticity is highly individualized, and is often distributed differently across arms, trunk, and legs. Despite the fact that traditional definitions of spasticity focus on reflex responsiveness, the stiffness associated with spasticity appears to be more problematic than spasms or clonus. The self-described characteristics of spasticity and its physiological presentation are complex and related to pain. This varied presentation lends support to the concept that management of spasticity may be best achieved by multimodality strategies.

Modification of altered ankle motor control after stroke using focal application of botulinum toxin type A.

STUDY DESIGN: Blinded, placebo-controlled, prospective clinical trial. PURPOSE: To examine the effects of botulinum toxin type A (BTX-A) injections into plantar flexor muscles in stroke patients with equinovarus gait. SUBJECTS: 15 post-stroke and 10 matched neurologically intact subjects. METHODS: Modified Ashworth Scale (MAS) and Fugl-Meyer assessment of physical function scale scores along with surface EMG collected before and up to 12 weeks after BTX-A injections to plantar flexor muscle motor points in stroke subjects. Saline placebo injections were performed in a subset of stroke subject group. RESULTS: MAS scores were decreased at 4, 8 and 12 weeks but F-M scores did not improve until 12 weeks post injection. Multi-muscle EMG patterns showed the return of volitional dorsiflexor activity in 11 and a decrease of antagonistic and distant coactivation in all but one of the 15. CONCLUSIONS: BTX-A is effective in reducing antagonistic and distant muscle activation that impedes volitional dorsiflexion.

Neurophysiological characterization of the 'new anatomy' and motor control that results from neurological injury or disease.

Following injury or disease, the central nervous system (CNS), to varying degrees, loses neurons, synaptic connections and conduction-promoting myelin insulation altering the neural circuitry assembled during development. This "New Anatomy" changes neural processing, bringing spasticity, paresis and paralysis to motor function and altered sensation, numbness and pain to sensory function. Focusing on the effects of CNS damage on the motor subsystems, this review offers a neurophysiological assessment perspective developed within the study of human spinal cord injury and extends it to other CNS disorders. It puts forward the concept that there are essential domains of CNS processing, altered by most neurological disorders, that are temporal, the speed of activation and deactivation, and spatial, the distribution across multiple muscles of motor units selected and activated. Measured through multiple-muscle recordings of selected motor-task performance, these domains can be useful in quantifying the severity of CNS damage and changes achieved through recovery or treatment.

Restorative neurology: consideration of the new anatomy and physiology of the injured nervous system.

The adult human nervous system is an incredibly complex set of thousands to tens of thousands of connections between a hundred billion neurons that develops via an intricate spatial-temporal process and is shaped by experience. In addition, any one anatomical arrangement of neural circuits is usually capable of multiple physiological states. Following neurological injury, a new anatomy, and consequently a new spectrum of physiology, emerges within this nervous system with its mix of both injured and uninjured parts. It is this new combination of neural components that determines the extent to which natural functional recovery can occur and the extent to which clinical interventions can further that recovery. Detecting the new anatomy and physiology of the injured human nervous system is difficult but not impossible and some methods can track over time changes in neural structure or, more often, functions that correlate with neurological improvement. The goal of restorative neurology is to make best use of this new anatomy and physiology to facilitate neurological recovery. While we are still learning about how neurorehabilitation interventions generate functional recovery, we can begin to test hypothesis regarding the underlying mechanisms of neural plasticity and attempt to augment those processes.