Balance Difficulties Research Articles

Is Difficulty with Balance Different from Difficulty Walking in Parkinson's Disease? (P06.047)

Objective: To determine whether difficulty with balance is different from difficulty walking and whether one or the other is more likely to result in falls. Background Patients with Parkinson9s disease (PD) suffer from disorders of balance and walking. Usually, the difficulty walking responds to anti-PD drugs and deep brain stimulation (DBS) but the balance difficulty may not. There is a need to develop a means of distinguishing one from the other to facilitate treatment. Design/Methods: Balance was studied using the self-administered Barrow Neurological Institute (BNI) question in 102 PD patients. The results were compared with those of the self-administered walking and balance question from the Experiences of Daily Living (EDL ) of the revised Unified Parkinson9s Disease Rating Scale (UPDRS) and with the UPDRS subtests of postural stability (PS), and the “pull test” - a test of balance. T-tests and/or chi-square tests were used to compare the appropriate variables. Results: Fifty-five of 102 patients reported difficulty on the BNI question and 64 patients reported difficulty on the UPDRS question. The patients who reported difficulty on either question had a significantly longer duration of PD and a higher UPDRS motor score. Of the patients who reported difficulty on the BNI question, 74.5% had a PS score ≥ 2 and 25.4% had at least 3 falls per month. Of the patients who reported difficulty on the UPDRS question, only 59.4 % had a PS score ≥ 2 and only 10.9% had at least 3 falls per month. Conclusions: The BNI balance question is better able to detect balance difficulty and falls than the walking and balance question on the UPDRS. The BNI question will be useful in evaluating patients before (and after) pharmacological and surgical procedures that impact balance. Disclosure: Dr. Lieberman has nothing to disclose. Dr. Krishnamurthi has nothing to disclose. Dr. Santiago has nothing to disclose. Dr. Dhall has received personal compensation for activities with Teva Pharmacuticals as a speaker. Dr. Moguel-Cobos has nothing to disclose. Dr. Sadreddin has nothing to disclose. Dr. Husain has nothing to disclose. Dr. Salins has nothing to disclose. Dr. Pan has nothing to disclose. Dr. Dhanani has nothing to disclose.

The Value of the Barrow Neurological Institute Balance Scale in Predicting Falls (P06.043)

Objective: A novel Barrow Neurological Institute (BNI) balance scale has been developed and its effectiveness in identifying falls examined. Background In Parkinson disease (PD), balance difficulty has been shown to correlate with falls. The revised Unified Parkinson Disease Rating Scale (UPDRS), however, is not focused to identify people with falls. Consequently, we developed the BNI balance scale as a complement to the UPDRS. Design/Methods: We compared the BNI scale with the Tinetti scale, a widely used scale for assessing fall risks, in 53 PD patients, 9 of whom fell ≥ 3 times per month (fallers). The BNI scale consists of evaluating balance during standing on one foot, turning, and tandem walking. All patients were also examined utilizing the motor part of the UPDRS during medication-on state. A t-test was used to compare continuous variables, a chi- square test to compare categorical variables, and a logistic regression model was constructed to predict sensitivities and specificities. Results: The fallers had a longer PD duration, a higher UPDRS score, a higher (worse) BNI balance score and a lower (worse) Tinetti score than non-fallers. All differences were significant. Fallers were more significantly impaired than non-fallers on the UPDRS postural stability and on the BNI subtests of standing on one foot, turning, and tandem walking. The BNI scale, score ≥ 10, had a sensitivity of 100 % and a specificity of 88.6% in predicting falls. The Tinetti scale, score Conclusions: The BNI balance scale is more sensitive and as specific in predicting falls than the Tinetti. The BNI balance scale takes less than one third of the time to perform than the Tinetti and is a necessary complement to the UPDRS for predicting falls. Disclosure: Dr. Husain has nothing to disclose. Dr. Krishnamurthi has nothing to disclose. Dr. Santiago has nothing to disclose. Dr. Dhall has received personal compensation for activities with Teva Pharmacuticals as a speaker. Dr. Moguel-Cobos has nothing to disclose. Dr. Sadreddin has nothing to disclose. Dr. Salins has nothing to disclose. Dr. Pan has nothing to disclose. Dr. Lieberman has nothing to disclose. Dr. Dhanani has nothing to disclose.

Prescription of foot and ankle orthoses for children with Charcot–Marie–Tooth disease: a review of the evidence

Background: Charcot–Marie–Tooth disease (CMT) is the most common inherited peripheral neuropathy and is associated with debilitating lower limb impairments and activity limitations. These impairments and activity limitations are potentially amendable to the prescription of orthoses, yet there is no universal, literature-based consensus to inform the decision making process of whether or not orthoses are indicated for a particular child with CMT, and if so, what type of device.Objectives: The aims of this paper were to: (1) review the lower limb impairments and activity limitations of children with CMT; (2) review the indications of commonly prescribed foot and ankle orthoses; and (3) formulate a clinical algorithm for the optimal prescription of foot and ankle orthoses for children with CMT.Major findings: We conducted a comprehensive search of the major databases and reference lists of relevant articles and books. In general, in-shoe orthoses are indicated for children with CMT and pes cavus and foot pain and/or mild balance impairments, whilst ankle-foot orthoses are indicated for children with CMT and pes cavus, foot drop, global foot and ankle muscle weakness and/or ankle equinus, and moderate-severe balance impairments and/or difficulty walking.Conclusions: A clinical algorithm is proposed to guide the prescription of foot and ankle orthoses for children with CMT. Further research is required to determine the efficacy of different foot and ankle orthoses, and the predictive ability of the proposed clinical algorithm, to improve the lower limb impairments and activity limitations of children with CMT.

Falls in Older Adults in Acute Care Found Common but Also Preventable

SAN FRANCISCO – Dr. Edgar Pierluissi, medical director of the Acute Care for Elders Unit at San Francisco General Hospital, recently looked at falls in elders by the numbers. First, they’re the number one cause of hip fractures, he reminded his audience at a conference on osteoporosis sponsored by the University of California, San Francisco. Other numbers from Dr. Pierluissi: 75: Physicians should ask patients aged 75 years or older if they’ve had any falls in the prior year or if they have balance or gait difficulties and observe them walking and getting into and out of a chair. 3–4: A fall in the previous year increases the risk for a future fall 3to 4-fold. 50: Studies suggest that 50% of adults over age 80 years will fall in the next year. 31: Falls in adults aged 65 years or older cause injury in approximately 31% of cases. 4: Muscle weakness quadruples the risk for a fall. 3: A gait deficit, balance deficit, or use of an assistive device nearly triples the risk for falling. 2: A visual deficit, arthritis, depression, or impaired activities of daily living more than double the risk for a fall. Cognitive impairment, use of some types of medications, or age older than 80 years each nearly doubles the risk for falling. 111: A Cochrane Review of 111 randomized controlled trials with 55,303 participants identified effective interventions to reduce the risk of falling (Cochrane Database Syst. Rev. 2009 [doi:10.1002/14651858.CD007146. pub2]). A number of forms of exercise reduced falls. Group tai chi exercise or multiplecomponent group exercise was effective if it targeted at least two of the following: strength, balance, flexibility, and endurance. Conducting a multifactorial falls evaluation reduces the number of falls. In patients with visual impairment and a high risk of falling, assessing and modifying home hazards was effective. Withdrawing psychotropic medications and educating primary care physicians about the risk of falls association with drug therapy reduced the number of falls but not the number who fell. Vitamin D supplementation may reduce falls in people with low vitamin D levels, but it’s unclear whether this helps people with adequate vitamin D levels. The Cochrane Review suggested that wearing hip protectors may provide some marginally significant benefit to frail, older adults in institutional care but not to older people who remain ambulant in the community, Dr. Pierluissi said. One randomized controlled trial of 1,042 residents in 37 nursing homes found a high rate of adherence to wearing hip protectors (74%) but these did not reduce the risk for hip fracture during the 20-month study. Residents served as their own controls by wearing hip protectors with padding on one hip but not the other. Investigators stopped the study early due to lack of efficacy, with hip fractures on 3.1% of the protected hips and 2.5% of unprotected hips, a statistically nonsignificant difference (JAMA 2007;298:413-22). Dr. Pierluissi said he has no relevant conflict of interest. CfA

P-994 - Determinants of functional status of first-time fathers in postpartum

The birth of a child, specially the first born, is a stage in the family life that brings with it changes both socially and professionally, changing previous balance. The transition to parenthood by the father implies skills to balance stress and difficulties. To analyse the association of some socio-demographic and obstetrical factors and the functional status of first-time fathers in the six weeks after childbirth. Cross-sectional study, with a consecutive non probabilistic sample of 204 first-time fathers from a health centre whose partner pregnancies, delivery and postpartum period without complications, and had a childbirth of a term newborn. The data were gathered in the six weeks postpartum from a self-administered questionnaire with socio-demographic and obstetrics questions and the Portuguese version of the Inventory of functional Status - fathers (IFS-F) after the approval of the ethic committee. The first-time fathers showed better functional status in terms of professional activities, community, social activities and housekeeping. It appears that the first-time fathers showed poorer functional status at the level of educational training, care of newborn and personal care activities. The older first-time fathers tend to show better functional status at the level of household activities. This study concludes that functional status of first-time fathers isn’t affected by educational level, residence, marital status or by the pregnancy vigilance place but partially influenced by the father's age and employment situation. This study provides information's to adequate care strategy to promote better functional status of first-time fathers in the postpartum period.

The Methodological Challenges of Research into Dance for People with Parkinson's

Parkinson's is a neurodegenerative disease that affects one in 500 people. It is a condition that affects the ability to initiate movement, to keep movement going and to stop movement voluntarily. Often, symptoms manifest themselves as limb tremors, rigidity of muscles, slowness of movement, a lack of co-ordination and difficulty in balancing. Many people with Parkinson's fall regularly and many feel socially isolated. There is no cure, and drugs to alleviate symptoms can be unreliable, sometimes even resulting in involuntary movement (dyskinesia) and hallucinations.There is a small but growing network of dance practitioners who deliver group dance sessions to those with Parkinson's. Evidence suggests that temporary relief of some symptoms is afforded by dancing to music and that dancing aids some people with Parkinson's to cope better with everyday actions. Most dance practitioners, however, approach sessions as a way for people to engage in an artistic and social practice. This paper was written at the start of a mixed-methods research project carried out in conjunction with English National Ballet, whose Department of Learning piloted twelve dance sessions for people with Parkinson's based on Nureyev's Romeo and Juliet. It discusses the tension between characterising dance as a rehabilitative therapy and perceiving it as an artistic and social practice.Most Parkinson's research has focused on finding a cure through neurological, biomechanical and pharmaceutical explorations. There has also been a reliance on numerical data for quality of life reports. In addition, the majority of research examining dance for people with Parkinson's has used quantitative methods and has focused on clinical benefits afforded by dance. The dominance of, and perceived need for, ‘hard’ scientific research methods and analysis prove a challenge to the qualitative researcher, who comes with a different viewpoint on how we know and understand the world, and with different ways of researching. The paper will argue that a dance researcher with a different methodological base can also offer potentially useful insight into the individuals who have this neurological condition, an insight different to that offered by quantitative research. Using sociological tools, such as interview and observation techniques, the qualitative researcher may examine participants’ lived experience of dancing with a body that moves in an unpredictable and atypical manner, as well as analysing the context in which this experience takes place. There is a need to focus attention on the dancing person, rather than merely on his or her disease.The paper reviews the literature on dance for people with Parkinson's, as well as outlining the traditional methodologies used to examine the disease and its symptoms. In doing so, it identifies the gaps in knowledge that could be explored through qualitative approaches, as well as how such approaches may be of use in strengthening ideas proposed by scientific methods. Through scoping arguments made by disability studies scholars, the paper goes on to advocate for a qualitative approach that critically engages with context, language and actions, but that also acknowledges the materiality of the body. By placing the person and his or her experiences at the centre of research, it argues that a qualitative study is well placed to examine how a person can ascribe value to dance as an artistic and social practice, while attempting to cope with a debilitating condition through dancing.

Functional correlates of gait and balance difficulty in essential tremor: Balance confidence, near misses and falls

BackgroundAlthough a mild objective abnormality of gait and balance has been observed in essential tremor (ET) cases in research settings, the clinical significance of this finding for patients is far from clear. In this study, we assessed whether ET patients subjectively experience more gait difficulty, more falls or near misses than controls. MethodsActivities-specific Balance Confidence (ABC) scores were obtained in 59 ET cases (15 with head tremor and 44 without head tremor) and 82 controls enrolled in a clinical-epidemiological study. ResultsABC scores were lower in ET cases than controls (61.8±27.7 vs. 70.3±28.1, p=0.035) of similar age (71.2±14.6 years vs. 71. 6±0.8 years), indicating significantly lower balance confidence in cases. The lowest scores (51.4±26.9) were observed in cases with head tremor (p=0.02). Near misses in the past year were the highest in cases with head tremor (67.3±112.1) and lowest in controls (6.1±33.3, p=0.008). The proportion who had had ≥5 near misses or falls in the past year was 11 (13.4%) for controls, 8 (18.2%) for cases without head tremor and 6 (40.0%) for cases with head tremor (p=0.048). For the ABC score, we created a receiver operating curve (ROC) curve and optimal cut-off score to differentiate between our two most different groups, namely, ET with head tremor and controls. Using this cut-off (≤67), sensitivity and specificity were moderate. ConclusionsET patients experience a loss of confidence in balance. The subgroup of patients with head tremor experienced the most gait and balance difficulty, with nearly one-in-two having had multiple near misses or falls during the previous year.

Dynamical geochemistry of the mantle

Abstract. The reconciliation of mantle chemistry with the structure of the mantle inferred from geophysics and dynamical modelling has been a long-standing problem. This paper reviews three main aspects. First, extensions and refinements of dynamical modelling and theory of mantle processing over the past decade. Second, a recent reconsideration of the implications of mantle heterogeneity for melting, melt migration, mantle differentiation and mantle segregation. Third, a recent proposed shift in the primitive chemical baseline of the mantle inferred from observations of non-chondritic 142Nd in the Earth. It seems most issues can now be resolved, except the level of heating required to maintain the mantle's thermal evolution. A reconciliation of refractory trace elements and their isotopes with the dynamical mantle, proposed and given preliminary quantification by Hofmann, White and Christensen, has been strengthened by work over the past decade. The apparent age of lead isotopes and the broad refractory-element differences among and between ocean island basalts (OIBs) and mid-ocean ridge basalts (MORBs) can now be quantitatively accounted for with some assurance. The association of the least radiogenic helium with relatively depleted sources and their location in the mantle have been enigmatic. The least radiogenic helium samples have recently been recognised as matching the proposed non-chondritic primitive mantle. It has also been proposed recently that noble gases reside in a so-called hybrid pyroxenite assemblage that is the result of melt from fusible pods reacting with surrounding refractory peridotite and refreezing. Hybrid pyroxenite that is off-axis may not remelt and erupt at MORs, so its volatile constituents would recirculate within the mantle. Hybrid pyroxenite is likely to be denser than average mantle, and thus some would tend to settle in the D" zone at the base of the mantle, along with some old subducted oceanic crust. Residence times in D" are longer, so the hybrid pyroxenite there would be less degassed. Plumes would sample both the degassed, enriched old oceanic crust and the gassy, less enriched hybrid pyroxenite and deliver them to OIBs. These findings can account quantitatively for the main He, Ne and Ar isotopic observations. It has been commonly inferred that the MORB source is strongly depleted of incompatible elements. However it has recently been argued that conventional estimates of the MORB source composition fail to take full account of mantle heterogeneity, and in particular focus on an ill-defined "depleted" mantle component while neglecting less common enriched components. Previous estimates have also been tied to the composition of peridotites, but these probably do not reflect the full complement of incompatible elements in the heterogeneous mantle. New estimates that account for enriched mantle components suggest the MORB source complement of incompatibles could be as much as 50–100 % larger than previous estimates. A major difficulty has been the inference that mass balances of incompatible trace elements could only be satisfied if there is a deep enriched layer in the mantle, but the Earth's topography precludes such a layer. The difficulty might be resolved if either the Earth is depleted relative to chondritic or the MORB source is less depleted than previous estimates. Together these factors can certainly resolve the mass balance difficulties.

Upper extremity joint stresses during walkerassisted ambulation in post-surgical patients

A walker is a common device prescribed for ambulatory assistance for individuals with balance difficulties or to reduce lower extremity demands following injury or surgery. The long-term use of a walker imposes significant demands on the patient's upper extremities that may lead to increased risk for development of secondary conditions such as wrist, elbow or shoulder pain. To describe the joint kinematics, forces and moments of the wrist, elbow and shoulder in a sample of twenty patients that were using a walker as a result of total joint surgery of the hips and knees. Three-dimensional upper extremity kinematics were recorded using a motion capture system synchronized with forces and torques transmitted through a walker instrumented with force transducers in the handles. Compressive forces were found to be nearly 20% of the body weight at each of the upper extremity joints, both surgical and non-surgical sides, being the greatest force at the wrist and decreasing proximally. Compression forces were greater in the non-surgical side limb at the wrist and at the elbow. Our findings indicated that loads on upper extremity joints associated with the use of a walker for assisted ambulation are high and further studies are needed to address the cause-effect relationship between the actual joint loading and the development of secondary musculoskeletal upper extremity complaints in more frail patients.

2011 APSA Teaching and Learning Conference Track Summaries

In a weekend of pedagogical fury, members of the Simulations and Role Play II track queried their peers to refine their ideas, presented data on the effectiveness of simulations as pedagogical tools, and shared methods of using simulations in the classroom. Paper presentations and discussions examined simulations from a variety of paradigmatic perspectives, including the use of simulations as summative assessment instruments, the role of competition in generating targeted learning outcomes, and the difficulty in balancing pedagogical objectives with design constraints.

Motor skill deficits in children with partial hearing

We examined the effect of partial hearing, including cochlear implantation, on the development of motor skills in children (aged 6-12y). Three independent groups of children were selected: a partial hearing group (n=25 [14 males, 11 females]; mean age 8y 8mo, SD 1y 10mo), a nonverbal IQ-matched group (n=27 [15 males, 12 females]; mean age 9y, SD 1y 6mo), and an age-matched group (n=26 [8 males, 18 females]; mean age 8y 8mo, SD 1y 7mo) from three schools with special units for children with partial hearing. All children with partial hearing had a bilateral hearing loss >60 decibels. Motor and balance skills were assessed using the Movement Assessment Battery for Children (MABC) and two protocols from the NeuroCom Balance Master clinical procedures. The mean standardized total MABC score of the children with partial hearing (95% confidence interval [CI] 71.8-88.7) was significantly lower than both the age-matched (95% CI 95.8-111.4; p<0.01) and the IQ-matched (95% CI 87.6-103.0; p=0.03) comparison groups. The children with partial hearing had particular difficulties with balance, most notably during tests of intersensory demand. However, subgroup analyses revealed that the effect of cochlear implantation was clearly dependent on the nature of the task. Children with partial hearing are at high risk of clinical levels of motor deficit, with balance difficulties providing support for conventional vestibular deficit theory. However, the effect of cochlear implantation suggests that other sensory systems may be involved. A broader ecological perspective, which takes into account factors external to the child, may prove a useful framework for future research.

MicroRNA-sensitive Oncolytic Measles Viruses for Cancer-specific Vector Tropism

Oncolytic measles viruses (MV) derived from the live attenuated vaccine strain have been engineered for increased tumor-cell specificity, and are currently under investigation in clinical trials including a phase I study for glioblastoma multiforme (GBM). Recent preclinical studies have shown that the cellular tropism of several viruses can be controlled by inserting microRNA-target sequences into their genomes, thereby inhibiting spread in tissues expressing cognate microRNAs. Since neuron-specific microRNA-7 is downregulated in gliomas but highly expressed in normal brain tissue, we engineered a microRNA-sensitive virus containing target sites for microRNA-7 in the 3'-untranslated region of the viral fusion gene. In presence of microRNA-7 this modification inhibits translation of envelope proteins, restricts viral spread, and progeny production. Even though highly attenuated in presence of microRNA-7, this virus retained full efficacy against glioblastoma xenografts. Furthermore, microRNA-mediated inhibition protected genetically modified mice susceptible to MV infection from a potentially lethal intracerebral challenge. Importantly, endogenous microRNA-7 expression in primary human brain resections tightly restricted replication and spread of microRNA-sensitive virus. This is proof-of-concept that tropism restriction by tissue-specific microRNAs can be adapted to oncolytic MV to regulate viral replication and gene expression to maximize tumor specificity without compromising oncolytic efficacy.

Hypocretin Antagonists in Insomnia Treatment and Beyond

Hypocretin neuropeptides have been shown to regulate transitions between wakefulness and sleep through stabilization of sleep promoting GABAergic and wake promoting cholinergic/monoaminergic neural pathways. Hypocretin also influences other physiologic processes such as metabolism, appetite, learning and memory, reward and addiction, and ventilatory drive. The discovery of hypocretin and its effect upon the sleep-wake cycle has led to the development of a new class of pharmacologic agents that antagonize the physiologic effects of hypocretin (i.e. hypocretin antagonists). Further investigation of these agents may lead to novel therapies for insomnia without the side-effect profile of currently available hypnotics (e.g. impaired cognition, confusional arousals, and motor balance difficulties). However, antagonizing a system that regulates the sleep-wake cycle while also influencing non-sleep physiologic processes may create an entirely different but equally concerning side-effect profile such as transient loss of muscle tone (i.e. cataplexy) and a dampened respiratory drive. In this review, we will discuss the discovery of hypocretin and its receptors, hypocretin and the sleep-wake cycle, hypocretin antagonists in the treatment of insomnia, and other implicated functions of the hypocretin system.

Selection of Brain Metastasis-Initiating Breast Cancer Cells Determined by Growth on Hard Agar

An approach that facilitates rapid isolation and characterization of tumor cells with enhanced metastatic potential is highly desirable. Here, we demonstrate that plating GI-101A human breast cancer cells on hard (0.9%) agar selects for the subpopulation of metastasis-initiating cells. The agar-selected cells, designated GI-AGR, were homogeneous for CD44(+) and CD133(+) and five times more invasive than the parental GI-101A cells. Moreover, mice injected with GI-AGR cells had significantly more experimental brain metastases and shorter overall survival than did mice injected with GI-101A cells. Comparative gene expression analysis revealed that GI-AGR cells were markedly distinct from the parental cells but shared an overlapping pattern of gene expression with the GI-101A subline GI-BRN, which was generated by repeated in vivo recycling of GI-101A cells in an experimental brain metastasis model. Data mining on 216 genes shared between GI-AGR and GI-BRN breast cancer cells suggested that the molecular phenotype of these cells is consistent with that of cancer stem cells and the aggressive basal subtype of breast cancer. Collectively, these results demonstrate that analysis of cell growth in a hard agar assay is a powerful tool for selecting metastasis-initiating cells in a heterogeneous population of breast cancer cells, and that such selected cells have properties similar to those of tumor cells that are selected based on their potential to form metastases in mice.

Test–retest reliability of the assessment of postural stability in typically developing children and in hearing impaired children

The purpose of this study was to establish test–retest reliability of centre of pressure (COP) measurements obtained by an AccuGait portable forceplate (ACG), mean COG sway velocity measured by a Basic Balance Master (BBM) and clinical balance tests in children with and without balance difficulties. 49 typically developing children and 23 hearing impaired children, with a higher risk for stability problems, between 6 and 12years of age participated. Each child performed the modified Clinical Test of Sensory Interaction on Balance (mCTSIB), Unilateral Stance (US) and Tandem Stance on ACG, mCTSIB and US on BBM and clinical balance tests: one-leg standing, balance beam walking and one-leg hopping. All subjects completed 2 test sessions on 2 different days in the same week assessed by the same examiner. Among COP measurements obtained by the ACG, mean sway velocity was the most reliable parameter with all ICCs higher than 0.72. The standard deviation (SD) of sway velocity, sway area, SD of anterior–posterior and SD of medio-lateral COP data showed moderate to excellent reliability with ICCs between 0.55 and 0.96 but some caution must be taken into account in some conditions. BBM is less reliable but clinical balance tests are as reliable as ACG. Hearing impaired children exhibited better relative reliability (ICC) and comparable absolute reliability (SEM) for most balance parameters compared to typically developing children.Reliable information regarding postural stability of typically developing children and hearing impaired children may be obtained utilizing COP measurements generated by an AccuGait system and clinical balance tests.

Thoracic Syrinx in a Patient With Balance Difficulties

The patient was a 42-year-old woman who was referred to a physical therapist with diagnoses of lumbar degenerative joint disease and a left ankle fracture. The patient reported an insidious onset of low back and left lower extremity pain, which began approximately 2 years prior to referral. She reported having difficulties with balance, which ultimately led to a fall 1 year after her low back and left lower extremity pain began. Her fall resulted in a left ankle fracture that required open reduction and internal fixation. Magnetic resonance imaging of her brain and spine revealed a diffuse, abnormally increased cord signal. The patient was diagnosed with a thoracic syrinx, which is a longitudinal fluid-filled cavity along the spinal cord. The patient underwent a T5-T6 hemilaminectomy, with placement of a syringopleural shunt between T4 and T6. Following surgery, the patient's neurologic status stabilized and did not deteriorate any further. J Orthop Sports Phys Ther 2011;41(4):282. doi:10.2519/jospt.2011.0408

Balance and reading are separate symptoms of dyslexia

Research into dyslexia has been characterized by controversy, but the issue of balance and whether or not it should be seen as causal in dyslexia has been one of the most heatedly debated issues in recent years. The consensus of research into balance and dyslexia over a 20-year period has been that balance deficits may be identified in around 50% of a sample of children with dyslexia and around 20% of a sample of adults with dyslexia. It has also been argued that any evidence of balance deficits may be attributed to comorbid attention deficit in the participants with dyslexia studied. However, recent evidence from the Sheffield group has established that deficits may be found in adults if the level of difficulty is manipulated in dual task paradigms1 and has demonstrated that balance difficulties are found in children and adults with dyslexia with age-appropriate tests even when attention-deficit–hyperactivity disorder is controlled for.2 Balance deficits have been linked to the cerebellum in the cerebellar deficit hypothesis of dyslexia,3 which argues that both balance and reading deficits in dyslexia may be explained by differences in processing, based on cerebellar dysfunction. This is an explanatory theory which provides an independent explanation of the other major theories of dyslexia, in particular the phonological deficit and double-deficit theories of dyslexia. The cerebellar hypothesis itself has generated further controversy, in particular as to whether the cerebellum is a causal factor in dyslexia or whether it should be seen as simply an ‘innocent bystander’. The basis for these disputes rests on a simple misunderstanding and confusion between reading deficits and dyslexia. The cerebellar deficit claims only that the language-related regions of the cerebellum are affected in dyslexia. These are generally considered to be lobule VI and VIIB in the neocerebellum – well away from the motor and balance regions in the cerebellum. Other cerebellar regions may also be affected, but this is not necessary. The ontogenetic causal chain for dyslexia,3 which outlines development from birth to 8 years, makes it clear that balance deficits are not directly linked to reading deficits, because they involve a separate route in the causal chain. The cerebellar deficit hypothesis would therefore predict a higher incidence of balance difficulties in dyslexia, but that these would not necessarily be directly correlated with reading difficulties. The balance difficulties are best seen as symptoms of dyslexia which may be identified before children fail to learn to read, and which are therefore particularly useful in screening tests for dyslexia, such as the Dyslexia Early Screening Test.4 This is precisely the pattern which is identified in the family study by Viholainen et al.5 The incidence of balance deficits in children with family risk for dyslexia is significantly higher than controls, but reading deficits are more highly significant in this group. This study provides further confirmation of the importance of family studies in our understanding of dyslexia. More recent research has suggested that it may be fruitful to subsume the cerebellar deficit hypothesis within a ‘neural systems’ framework that attempts to capture disorders of learning at the level of the systems that work together, rather than the specific brain structures.6 This framework suggests that for dyslexia the neural system involved is the language-specific procedural learning system. The framework provides a natural explanation for the comorbidities found in dyslexia and it may have the potential to reunite the developmental disabilities.

A Tale of Two Tauopathies

A 77-year-old man developed progressive language and balance difficulties. He had difficulty rising from a chair, with falls occurring within the first year of symptoms. After 1 year, rapid, spontaneous jerks appeared in the left hand, which he described as “useless.” Neurologic examination 3 years after his initial symptoms demonstrated 23/30 on the Mini-Mental State Examination and an applause sign. He had apathy, without a pseudobulbar affect. Aside from mild word-finding difficulties, his language examination was normal. Cranial nerve examination showed vertical gaze limitation with loss of vertical fast phases on testing of optokinetic nystagmus (OKN). Vertical gaze limitations could be overcome with oculocephalic maneuvers. Motor examination revealed markedly increased tone in his left arm, with moderate left greater than right bradykinesia, without tremor. Left ideomotor apraxia was present. Action and postural myoclonus was present in the left arm. There was neck extension and axial rigidity. Gait was slow and slightly wide-based with impaired postural reflexes. Stereognosis and graphesthesia were intact. A trial of levodopa/carbidopa 900 mg per day showed no symptomatic benefit. Brain MRI without gadolinium revealed asymmetric, focal atrophy of the right frontoparietal area and the midbrain tegmentum (figure). Figure Brain MRI (A) Axial T1-weighted brain MRI shows atrophy of the …

Artificial neural network simulation of arm gait of Huntington disease patient

Huntington’s disease (HD) is an autosomal dominant neurodegenerative disease which usually affects the patients at middle age. Early motor signs of Huntington’s disease typically include the gradual onset of clumsiness, balance difficulties, and brief, random, fidgeting movements. This work is our attempt to promote a better understanding of the chorea associated with HD by carrying out an artificial neural network (ANN) simulation of the arm gait of an HD patient.

Contingent negative variation and activation of postural preparation before postural perturbation by backward floor translation at different initial standing positions

We investigated the effects of balance difficulty on contingent negative variation (CNV) and postural preparation against perturbation. Thirteen subjects were perturbed by a backward floor translation (S2) after an auditory warning stimulus. To alter balance difficulty, subjects maintained standing posture from four initial positions before perturbation. The position of the center of pressure in the anteroposterior direction (CoPy) was expressed as a percentage distance of foot length (%FL) from the heel: 10%FL anterior to extreme backward leaning; quiet standing (QS); and 20%FL and 10%FL posterior to extreme forward leaning. CNV, CoPy, and electromyography (EMG) of the lower leg muscles were analyzed. Balance difficulty was represented by the relative distance of the forward peak position of CoPy after S2 from the QS position. Balance difficulty was higher with a more anterior initial position. The late CNV peaked just before S2 (latency: −76 to −306 ms), then started becoming small. CNV peak was earlier and larger with increasing balance difficulty. CoPy backward shift and a continuous EMG increase were observed as the strategy for postural preparation, and were significantly earlier (61 ms and 42 ms, respectively) than the CNV peak. CNV peak time correlated closely with onset times of CoPy backward shift ( r = 0.78) and continuous EMG increase ( r = 0.71). These findings suggest that as balance difficulty increases, attentional allocation to sensory information and/or postural preparation starts earlier just before the perturbation.