EMA analysis of tongue function in children with dysarthria following traumatic brain injury

Primary objective : To investigate the speed and accuracy of tongue movements exhibited by a sample of children with dysarthria following severe traumatic brain injury (TBI) during speech using electromagnetic articulography (EMA). Methods and procedures : Four children, aged between 12.75-17.17 years with dysarthria following TBI, were assessed using the AG-100 electromagnetic articulography system (Carstens Medizinelektronik). The movement trajectories of receiver coils affixed to each child's tongue were examined during consonant productions, together with a range of quantitative kinematic parameters. The children's results were individually compared against the mean values obtained by a group of eight control children (mean age of 14.67 years, SD 1.60). Main outcomes and results : All four TBI children were perceived to exhibit reduced rates of speech and increased word durations. Objective EMA analysis revealed that two of the TBI children exhibited significantly longer consonant durations compared to the control group, resulting from different underlying mechanisms relating to speed generation capabilities and distances travelled. The other two TBI children did not exhibit increased initial consonant movement durations, suggesting that the vowels and/or final consonants may have been contributing to the increased word durations. Conclusions and clinical implications : The finding of different underlying articulatory kinematic profiles has important implications for the treatment of speech rate disturbances in children with dysarthria following TBI.

A pain neuromatrix approach to patients with chronic pain

This paper presents an approach to rehabilitation of pain patients. The fundamental principles of the approach are (i) pain is an output of the brain that is produced whenever the brain concludes that body tissue is in danger and action is required, and (ii) pain is a multisystem output that is produced when an individual-specific cortical pain neuromatrix is activated. When pain becomes chronic, the efficacy of the pain neuromatrix is strengthened via nociceptive and non-nociceptive mechanisms, which means that less input, both nociceptive and non-nociceptive, is required to produce pain. The clinical approach focuses on decreasing all inputs that imply that body tissue is in danger and then on activating components of the pain neuromatrix without activating its output. Rehabilitation progresses to increase exposure to threatening input across sensory and non-sensory domains. (C) 2003 Elsevier Ltd. All rights reserved.

General language abilities following management of childhood supratentorial tumour: Part 1

Background. To date few studies have investigated the impact of management for supratentorial tumour on the language abilities of children. In reporting children with brain tumour as part of a larger cohort of various aetiologies of brain injury, such studies have failed to differentiate between the causes of acquired childhood language disorders, or specifically report associated information relating to site and treatment. Material and methods. The present study examined the general language abilities of six children managed for supratentorial tumour, using a comprehensive standardized general language assessment battery, including receptive and expressive components, receptive vocabulary, and naming. Results. At a group level, children managed for supratentorial tumour performed below an individually matched control group in the area of general expressive language. However, at an individual case level it was revealed that only two cases exhibited specific language deficits. Reduced performance in the area of expressive language and syntax was evident in the language profile of one child treated surgically for a left parietal astrocytoma, while a child treated surgically for an optic nerve glioma demonstrated difficulties in receptive semantic abilities. The remaining four cases with similar treatments and locations demonstrated intact general language abilities. Conclusions. Factors such as site, long-term presence of tumour prior to diagnosis, young age at diagnosis, and variations in time post treatment were considered to have contributed to the findings. The need for long-term monitoring of language abilities post treatment as well as larger group sizes and the investigation of higher-level abilities was highlighted

Joining forces - Combining cognition-targeted motor control training with group or individual pain physiology education: A successful treatment for chronic low back pain

Chronic unremittent low back pain (LBP) is characterised by cognitive barriers to treatment. Combining a motor control training approach with individualised education about pain physiology is effective in this group of patients. This randomized comparative trial (i) evaluates an approach to motor control acquisition and training that considers the complexities of the relationship between pain and motor output, and (ii) compares the efficacy and cost of individualized and group pain physiology education. After an "ongoing usual treatment" period, patients participated in a 4-week motor control and pain physiology education program. Patients received four one-hour individualized education sessions (IE) or one 4-hour group lecture (GE). Both groups reduced pain (numerical rating scale) and disability (Roland Morris Disability Questionnaire). IE showed bigger decreases, which were maintained at 12 months (P < 0.05 for all). The combined motor control and education approach is effective. Although group education imparts a lesser effect, it may be more cost-efficient. [ABSTRACT FROM AUTHOR]

Evidence of altered lumbopelvic muscle recruitment in the presence of sacroiliac joint pain

Study Design. Cross-sectional study of electromyographic onsets of trunk and hip muscles in subjects with a clinical diagnosis of sacroiliac joint pain and matched control subjects. Objectives. To determine whether muscle activation of the supporting leg was different between control subjects and subjects with sacroiliac joint pain during hip flexion in standing. Background. Activation of the trunk and gluteal muscles stabilize the pelvis for load transference; however, the temporal pattern of muscle activation and the effect of pelvic pain on temporal parameters has not been investigated. Methods. Fourteen men with a clinical diagnosis of sacroiliac joint pain and healthy age-matched control subjects were studied. Surface electromyographic activity was recorded from seven trunk and hip muscles of the supporting leg during hip flexion in standing. Onset of muscle activity relative to initiation of the task was compared between groups and between limbs. Results. The onset of obliquus internus abdominis (OI) and multifidus occurred before initiation of weight transfer in the control subjects. the onset of obliquus internus abdominis, multifidus, and gluteus maximus was delayed on the symptomatic side in subjects with sacroiliac joint pain compared with control subjects, and the onset of biceps femoris electromyographic activity was earlier. IN addition, electromyographic onsets were different between the symptomatic and asymptomatic sides in subjects with sacroiliac joint pain. Conclusions. The delayed onset of obliquus internus abdominis, multifidus, and gluteus maximus electromyographic activity of the supporting leg during hip flexion, in subjects with sacroiliac joint pain. suggests an alteration in the strategy for lumbopelvic stabilization that may disrupt load transference through the pelvis.

Core stability exercise in chronic low back pain

Exercise is commonly used in the management of chronic musculoskeletal conditions, including chronic low back pain (CLBP). The focus of exercise is varied and may include parameters ranging from strength and endurance training, to specific training of muscle coordination and control. The assumption underpinning these approaches is that improved neuromuscular function will restore or augment the control and support of the spine and pelvis. In a biomechanical model of CLBP, which assumes that pain recurrence is caused by repeated mechanical irritation of pain sensitive structures [1], it is proposed that this improved control and stability would reduce mechanical irritation and lead to pain relief [1]. Although this model provides explanation for the chronicity of LBP, perpetuation of pain is more complex, and contemporary neuroscience holds the view that chronic pain is mediated by a range of changes including both peripheral (eg, peripheral sensitization) and central neuroplastic changes [2]. Although this does not exclude the role of improved control of the lumbar spine and pelvis in management of CLBP, particularly when there is peripheral sensitization, it highlights the need to look beyond outdated simplistic models. One factor that this information highlights is that the refinement of control and coordination may be more important than simple strength and endurance training for the trunk muscles. The objective of this article is to discuss the rationale for core stability exercise in the management of CLBP, to consider critical factors for its implementation, and to review evidence for efficacy of the approach.

Acoustic Investigation of Vocal Quality following Treatment for Childhood Cerebellar Tumour

The aim of the study was firstly to document the acoustic parameters of voice using the Multidimensional Voice Program (MDVP, Kay Elemetrics) in a group of children with dysarthria subsequent to treatment for cerebellar tumour (CT). Then, secondly, compare the acoustic findings to perceptual voice characteristics as described by the GIRBAS (grade, instability, roughness, breathiness, asthenicity, strain). The assessments were performed on 29 voice samples; 9 cerebellar tumour participants with dysarthria, and 20 control participants. None of the control voices were rated as exhibiting any of the six parameters described by the GIRBAS, while 7 of the CT participants were noted to have at least a mild voice disorder. Roughness, instability, breathiness and asthenicity were all identified as voice characteristics in the CT voice samples. Acoustically, the CT voice samples differed significantly from the controls' voices on frequency and amplitude perturbation measures. Our findings confirmed voice dysfunction as a component of dysarthria in children treated for cerebellar tumour, and discussed the links between acoustic and perceptual descriptions. Copyright (C) 2004 S. Karger AG, Basel.

Patients with chronic neck pain demonstrate altered patterns of muscle activation during performance of a functional upper limb task

Study Design. Cross-sectional study. Objective. This study compared neck muscle activation patterns during and after a repetitive upper limb task between patients with idiopathic neck pain, whiplash-associated disorders, and controls. Summary of Background Data. Previous studies have identified altered motor control of the upper trapezius during functional tasks in patients with neck pain. Whether the cervical flexor muscles demonstrate altered motor control during functional activities is unknown. Methods. Electromyographic activity was recorded from the sternocleidomastoid, anterior scalenes, and upper trapezius muscles. Root mean square electromyographic amplitude was calculated during and on completion of a functional task. Results. A general trend was evident to suggest greatest electromyograph amplitude in the sternocleidomastoid, anterior scalenes, and left upper trapezius muscles for the whiplash-associated disorders group, followed by the idiopathic group, with lowest electromyographic amplitude recorded for the control group. A reverse effect was apparent for the right upper trapezius muscle. The level of perceived disability ( Neck Disability Index score) had a significant effect on the electromyographic amplitude recorded between neck pain patients. Conclusions. Patients with neck pain demonstrated greater activation of accessory neck muscles during a repetitive upper limb task compared to asymptomatic controls. Greater activation of the cervical muscles in patients with neck pain may represent an altered pattern of motor control to compensate for reduced activation of painful muscles. Greater perceived disability among patients with neck pain accounted for the greater electromyographic amplitude of the superficial cervical muscles during performance of the functional task.

Unravelling the complexity of muscle impairment in chronic neck pain

Exercise interventions are deemed essential for the effective management of patients with neck pain. However, there has been a lack of consensus on optimal exercise prescription, which has resulted from a paucity of studies to quantify the precise nature of muscle impairment, in people with neck pain. This masterclass will present recent research from our laboratory, which has utilized surface electromyography to investigate cervical flexor muscle impairment in patients with chronic neck pain. This research has identified deficits in the motor control of the deep and superficial cervical flexor muscles in people with chronic neck pain, characterized by a delay in onset of neck muscle contraction associated with movement of the upper limb. In addition, people with neck pain demonstrate an altered pattern of muscle activation, which is characterized by reduced deep cervical flexor muscle activity during a low load cognitive task and increased activity of the superficial cervical flexor muscles during both cognitive tasks and functional activities. The results have demonstrated the complex, multifaceted nature of cervical muscle impairment, which exists in people with a history of neck pain. In turn, this has considerable implications for the rehabilitation of muscle function in people with neck pain disorders. (C) 2004 Elsevier Ltd. All rights reserved.

Spatio-temporal evaluation of neck muscle activation during postural perturbations in healthy subjects

The purpose of this study was to examine the spatio-temporal activation of the sternocleidomastoid (SCM) and cervical extensor (CE) muscles with respect to the deltoid muscle onset during rapid voluntary upper limb movement in healthy volunteers. The repeatability and reliability of the spatio-temporal aspects of the myoelectric signals were also examined. Ten subjects performed bilateral and unilateral rapid upper limb flexion, abduction and extension in response to a visual stimulus. EMG onsets and normalised root mean square (nRMS) values were calculated for the SCM and CE muscles. Subjects attended three testing sessions over non-consecutive days allowing the repeatability and reliability of these measures to be assessed. The SCM and CE muscles demonstrated feed-forward activation (activation within 50 ms of deltoid onset) during rapid arm movements in all directions. The sequence and magnitude of neck muscle activation displayed directional specificity, however, the neck flexor and extensor muscles displayed co-activation during all perturbations. EMG onsets demonstrated high repeatability in terms of repeated measure precision (nSEM in the range 1.9-5.7%). This was less evident for the repeatability of nRMS values. The results of this study provide a greater understanding of cervical neuromotor control strategies. During bilateral and unilateral upper limb perturbations, the SCM and CE muscles demonstrate feed-forward co-activation. It seems apparent that feed-forward activation of neck muscles is a mechanism necessary to achieve stability for the visual and vestibular systems, whilst ensuring stabilisation and protection of the cervical spine. (C) 2004 Elsevier Ltd. All rights reserved.