Comparison of posture and balance in cancer survivors and age-matched controls

Comparison of neuromuscular fatigability amplitude and etiologies between fatigued and non-fatigued cancer patients

PURPOSE

Cancer-related fatigue (CRF) is the most reported side effect of cancer and its treatments. Mechanisms of CRF are multidimensional, including neuromuscular alterations leading to decreased muscle strength and endurance (i.e., fatigability). Recently, exercise fatigability and CRF have been related, while fatigability mechanisms remain unclear. Traditionally, fatigability is assessed from maximal voluntary contractions (MVC) decrease, but some authors hypothesized that the rate of force development (RFD) determined during a rapid contraction could also be an interesting indicator of functional alterations. However, to our knowledge, no study investigated RFD in cancer patients. The purpose of this study was to determine whether RFD, fatigability amplitude, and etiology are different between fatigued and non-fatigued cancer patients.

METHODS

Eighteen participants with cancer, divided in fatigued or non-fatigued groups according their CRF level, completed a 5-min all-out exercise in ankle plantar flexor muscles composed of 62 isometric MVC of 4 s with 1 s rest, to assess fatigability amplitude as the force-time relationship asymptote (FA). Before and after exercise, fatigability etiologies (i.e., voluntary activation (VA) and evoked forces by electrical stimulation (Db100)) were assessed as well as RFD in 50 and 100 ms (RFD50 and RFD100, respectively) during rapid contractions.

RESULTS

FA is significantly lower in fatigued group. Significant differences were found between pre- and post-exercise VA, Db100, RFD50, and RFD100 for both groups, with no statistical difference between groups.

CONCLUSION

During treatments, fatigability is higher in fatigued patients; however, the mechanisms of fatigability and RFD alterations are similar in both groups.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04391543, May 2020.

Investigation of factors associated with static and dynamic balance in early-stage lung cancer survivors

PURPOSE

Balance impairment and falls are common among patients after cancer treatment. This study aimed to compare static and dynamic balance functions in lung cancer survivors (LCS) and healthy controls and to investigate the factors related to balance in LCS.

METHODS

Cross-sectional data were collected from lung cancer patients whose treatment had been completed within the previous 3 months (n = 60) and age and gender-matched healthy controls (n = 60). Clinical characteristics and history of falls were recorded. Pulmonary function tests and measurements of respiratory muscle strength were performed. Dynamic and static balance, fear of falling, knee-extension strength, physical activity level, dyspnea, comorbidity, and quality of life (QoL) were assessed using the Time Up and Go Test, Single Leg Standing Test, the Fall Efficacy Scale-International, hand-held dynamometer, the International Physical Activity Questionnaire, the Modified Medical Research Dyspnea Scale, the Charlson Comorbidity Index, and the European Organization for Research and Treatment of Cancer QoL Scale.

RESULTS

LCS reported a higher fall rate and exhibited lower dynamic balance compared to controls (p < 0.05). The number of chemotherapy cycles, number of falls in the past year, fear of falling, perceived dyspnea, forced expiratory volume in 1 s (%), maximal inspiratory pressure (%), knee-extension strength, physical activity score, and QoL score related to physical function were correlated with balance function in LCS (p < 0.05).

CONCLUSION

LCS had a higher risk of falls and lower dynamic balance function which might be related to various clinical and physical parameters.

IMPLICATIONS FOR CANCER SURVIVORS

Identifying factors related to balance should be considered within the scope of fall prevention approaches for these patients.

Exploring assessment of balance using virtual reality in patients at risk of chemotherapy-induced peripheral neuropathy

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a common dose-limiting toxicity for people treated for cancer. Impaired balance and falls are functional consequences of CIPN. Virtual reality (VR) technology may be able to assess balance and identify patients at risk of falls.

AIMS

To assess the impact of potentially neurotoxic chemotherapy on balance using VR, and explore associations between VR balance assessment, falls and CIPN.

METHODS

This prospective, repeated measures longitudinal study was conducted at two Australian cancer centres. Eligible participants were commencing adjuvant chemotherapy containing a taxane for breast cancer, or oxaliplatin for colorectal cancer (CRC), per institutional guidelines. Balance assessments using VR were conducted at baseline, end of chemotherapy and 3 and 6 months after completion of chemotherapy. Participants also completed a comprehensive CIPN assessment comprising clinical and patient-reported outcomes, and recorded falls or near falls.

RESULTS

Out of 34 participants consented, 24 (71%) had breast cancer and 10 (29%) had CRC. Compared to baseline, balance threshold was reduced in 10/28 (36%) evaluable participants assessed at the end of chemotherapy, and persistent in 7/22 (32%) at 6 months. CIPN was identified in 86% at end of chemotherapy and persisted to 6 months after chemotherapy completion in 73%. Falls or near falls were reported by 12/34 (35%) participants, and were associated with impaired VR balance threshold (P = 0.002).

CONCLUSIONS

While VR balance assessment was no better at identifying CIPN than existing measures, it is a potential surrogate method to assess patients at risk of falls from CIPN.

Beyond the treatment: The role of race, sex, and education in health trajectories between cancer survivors and noncancer older adults

INTRODUCTION

The number of older, long-term cancer survivors is increasing. However, little is known about how cancer and aging affect the health trajectories of older adults differently. In addition, the impact of race, sex, and education on the processes of aging and the cancer experience needs further investigation. The current study aims to address this knowledge gap by combining two National Cancer Institute (NIC)-funded longitudinal studies conducted in Cleveland from 1998 to 2010.

MATERIALS AND METHODS

The unique cross-sequential design facilitates a comparison between the health changes in long-term (five years +) older cancer survivors (breast, prostate, and colorectal cancer) and demographically matched older adults without a history of cancer in the same geographic area within the same period. The study also captured comprehensive information on how socioeconomic status interacts with cancer and aging over time. General linear models were employed in the data analysis.

RESULTS

The findings showed that early cancer experience did not affect long-term cancer survivors' health status in later life. Conversely, comorbidities, being an African American, being female, and having education less than a college degree significantly decreased the health trajectory in later life for all older adults. Moreover, compared to other groups, older African American cancer survivors reported a dramatic decrease in self-reported health after controlling for other conditions.

DISCUSSION

Study findings can inform public policy and social services to offer comprehensive treatment plans and help individuals overcome their diseases and lead longer and healthier lives.

Recent Findings in Physical Exercise for Cancer Survivors

In recent years, the number of cancer survivors has been increasing each year due to advances in the early diagnosis and treatment of cancer. Cancer survivors present a variety of physical and psychological complications due to cancer and its treatment. Physical exercise is an effective nonpharmacological treatment for complications in cancer survivors. Furthermore, recent evidence has shown that physical exercise improves the prognosis of cancer survivors. The benefits of physical exercise have been widely reported, and guidelines for physical exercise for cancer survivors have been published. These guidelines recommend that cancer survivors engage in moderate- or vigorous-intensity aerobic exercises and/or resistance training. However, many cancer survivors have a poor commitment to physical exercise. In the future, it is necessary to promote physical exercise among cancer survivors through outpatient rehabilitation and community support.

Using Wearable Inertial Sensors to Assess Mobility of Patients With Hematologic Cancer and Associations With Chemotherapy-Related Symptoms Before Autologous Hematopoietic Stem Cell Transplant: Cross-sectional Study

BACKGROUND

Wearable sensors could be a simple way to quantify and characterize mobility in patients with hematologic cancer scheduled to receive autologous hematopoietic stem cell transplant (autoHSCT) and how they may be related to common treatment-related symptoms and side effects of induction chemotherapy.

OBJECTIVE

We aimed to conduct a cross-sectional study comparing mobility in patients scheduled to receive autoHSCT with that in healthy, age-matched adult controls and determine the relationships between patient mobility and chemotherapy-related symptoms.

METHODS

Patients scheduled to receive autoHSCT (78/156, 50%) and controls (78/156, 50%) completed the prescribed performance tests using wearable inertial sensors to quantify mobility including turning (turn duration and number of steps), gait (gait speed, stride time, stride time variability, double support time, coronal trunk range of motion, heel strike angle, and distance traveled), and balance (coronal sway, coronal range, coronal velocity, coronal centroidal frequency, sagittal sway, sagittal range, sagittal velocity, and sagittal centroidal frequency). Patients completed the validated patient-reported questionnaires to assess symptoms common to chemotherapy: chemotherapy-induced peripheral neuropathy (Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity subscale), nausea and pain (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire), fatigue (Patient-Reported Outcomes Measurement Information System Fatigue Short Form 8a), vertigo (Vertigo Symptom Scale-short form), and depression (Center for Epidemiological Studies-Depression). Paired, 2-sided t tests were used to compare mobility between patients and controls. Stepwise multivariable linear regression models were used to evaluate associations between patient mobility and symptoms.

RESULTS

Patients aged 60.3 (SD 10.3) years had significantly worse turning (turn duration; P<.001), gait (gait speed, stride time, stride time variability, double support time, heel strike angle, stride length, and distance traveled; all P<.001), and balance (coronal sway; P<.001, range; P<.001, velocity; P=.02, and frequency; P=.02; and sagittal range; P=.008) than controls. In patients, high nausea was associated with worse stride time variability (ß=.001; P=.005) and heel strike angle (ß=-.088; P=.02). Pain was associated with worse gait speed (ß=-.003; P=.003), stride time variability (ß=.012; P=.02), stride length (ß=-.002; P=.004), and distance traveled (ß=-.786; P=.005). Nausea and pain explained 17% to 33% and 14% to 36% of gait variance measured in patients, respectively.

CONCLUSIONS

Patients scheduled to receive autoHSCT demonstrated worse mobility in multiple turning, gait, and balance domains compared with controls, potentially related in part to nausea and pain. Wearable inertial sensors used in the clinic setting could provide granular information about mobility before further treatment, which may in turn benefit from rehabilitation or symptom management. Future longitudinal studies are needed to better understand temporal changes in mobility and symptoms across the treatment trajectory to optimally time, design, and implement strategies, to preserve functioning in patients with hematologic cancer in the long term.

Mechanosensory encoding dysfunction emerges from cancer-chemotherapy interaction

Persistent sensory, motor and cognitive disabilities comprise chemotherapy-induced neural disorders (CIND) that limit quality of life with little therapeutic relief for cancer survivors. Our recent preclinical study provides new insight into a condition impacting the severity of chronic CIND. We find that sensorimotor disability observed following cancer treatment exceeds that attributable to chemotherapy alone. A possible explanation for intensified disability emerged from evidence that codependent effects of cancer and chemotherapy amplify defective firing in primary sensory neurons supplying one type of low threshold mechanosensory receptor (LTMR). Here we test whether cancer's modification of chemotherapy-induced sensory defects generalizes across eight LTMR submodalities that collectively generate the signals of origin for proprioceptive and tactile perception and guidance of body movement. Preclinical study enabled controlled comparison of the independent contributions of chemotherapy and cancer to their clinically relevant combined effects. We compared data sampled from rats that were otherwise healthy or bearing colon cancer and treated, or not, with human-scaled, standard-of-care chemotherapy with oxaliplatin. Action potential firing patterns encoding naturalistic mechanical perturbations of skeletal muscle and skin were measured electrophysiologically in vivo from multiple types of LTMR neurons. All expressed aberrant encoding of dynamic and/or static features of mechanical stimuli in healthy rats treated with chemotherapy, and surprisingly also by some LTMRs in cancer-bearing rats that were not treated. By comparison, chemotherapy and cancer in combination worsened encoding aberrations, especially in slowly adapting LTMRs supplying both muscle and glabrous skin. Probabilistic modeling best predicted observed encoding defects when incorporating interaction effects of cancer and chemotherapy. We conclude that for multiple mechanosensory submodalities, the severity of encoding defects is modulated by a codependence of chemotherapy side effects and cancer's systemic processes. We propose that the severity of CIND might be reduced by therapeutically targeting the mechanisms, yet to be determined, by which cancer magnifies chemotherapy's neural side effects as an alternative to reducing chemotherapy and its life-saving benefits.

Influence of chemotherapy on postural control and quality of life in women with gynaecological cancer: a protocol of a prospective observational study

INTRODUCTION

Chemotherapy-induced peripheral neuropathy is a frequent side effect of some chemotherapies that can cause postural control disorders and has a serious impact on quality of life (QoL). An enhanced understanding of postural control dysfunction could help build a systematic and accurate assessment as well as specific exercises to limit the impact on QoL. This study aims to assess the influence of chemotherapy on postural control and the QoL for women with gynaecological cancer.

METHODS AND ANALYSIS

This prospective observational study will include 37 participants with cancer treated using neurotoxic chemotherapy. Their postural control in various conditions (rigid and foam surfaces, eyes open and closed, with and without tendon vibration, and dual tasks), limits of stability, QoL and modified Total Neuropathy Score will be assessed. A linear mixed model will compare postural control pre-chemotherapy and post-chemotherapy.

ETHICS AND DISSEMINATION

This study was approved by an ethical review board in Geneva (CCER-2020-01639). The study findings will be disseminated through conference presentations and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04692168.

Expression Profiles of Circulating MicroRNAs in XELOX-Chemotherapy-Induced Peripheral Neuropathy in Patients with Advanced Gastric Cancer

Gastric cancer (GC) is one of the most common cancers and a leading cause of cancer deaths around the world. Chemotherapy is one of the most effective treatments for cancer patients, and has remarkably enhanced survival rates. However, it has many side effects. Recently, microRNAs (miRNAs) have been intensively studied as potential biomarkers for cancer diagnosis and treatment monitoring. However, definitive biomarkers in chemotherapy-induced peripheral neuropathy (CIPN) are still lacking. The aim of this study was to identify the factors significant for neurological adverse events in GC patients receiving XELOX (oxaliplatin and capecitabine) chemotherapy. The results show that XELOX chemotherapy induces changes in the expression of hsa-miR-200c-3p, hsa-miR-885-5p, and hsa-miR-378f. Validation by qRT-PCR demonstrated that hsa-miR-378f was significantly downregulated in CIPN. Hsa-miR-378f was identified as showing a statistically significant correlation in GC patients receiving XELOX chemotherapy according to the analysis of differentially expressed (DE) miRNAs. Furthermore, 34 potential target genes were predicted using a web-based database for miRNA target prognostication and functional annotations. The identified genes are related to the peptidyl-serine phosphorylation and regulation of alternative mRNA splicing with enrichment in the gastric cancer, neurotrophin, MAPK, and AMPK signaling pathways. Collectively, these results provide information useful for developing promising strategies for the treatment of XELOX-chemotherapy-induced peripheral neuropathy.

Neural circuit mechanisms of sensorimotor disability in cancer treatment

Cancer survivors rank sensorimotor disability among the most distressing, long-term consequences of chemotherapy. Disorders in gait, balance, and skilled movements are commonly assigned to chemotoxic damage of peripheral sensory neurons without consideration of the deterministic role played by the neural circuits that translate sensory information into movement. This oversight precludes sufficient, mechanistic understanding and contributes to the absence of effective treatment for reversing chemotherapy-induced disability. We rectified this omission through the use of a combination of electrophysiology, behavior, and modeling to study the operation of a spinal sensorimotor circuit in vivo in a rat model of chronic, oxaliplatin (chemotherapy)-induced neuropathy (cOIN). Key sequential events were studied in the encoding of propriosensory information and its circuit translation into the synaptic potentials produced in motoneurons. In cOIN rats, multiple classes of propriosensory neurons expressed defective firing that reduced accurate sensory representation of muscle mechanical responses to stretch. Accuracy degraded further in the translation of propriosensory signals into synaptic potentials as a result of defective mechanisms residing inside the spinal cord. These sequential, peripheral, and central defects compounded to drive the sensorimotor circuit into a functional collapse that was consequential in predicting the significant errors in propriosensory-guided movement behaviors demonstrated here in our rat model and reported for people with cOIN. We conclude that sensorimotor disability induced by cancer treatment emerges from the joint expression of independent defects occurring in both peripheral and central elements of sensorimotor circuits.

Relationship between balance function and QOL in cancer survivors and healthy subjects

A previous study reported that cancer survivors exhibit decreased postural stability compared to age-matched controls. Another study showed that cancer survivors have a lower quality of life (QOL) compared to healthy subjects, and there was a significant relationship between muscle strength and QOL in cancer survivors. We aimed to investigate differences in the associations between balance function and QOL in cancer survivors and healthy subjects.Forty-one cancer survivors and 33 healthy subjects were included. Balance function was evaluated using the timed up and go test, and body sway was tested using a force platform. QOL was assessed using the medical outcome study 36-item short-form health survey.Cancer survivors exhibited significantly higher timed up and go and lower QOL than that of healthy subjects (P < .05). There was a significant association between body sway and QOL (P < .05) among cancer survivors. However, healthy subjects had subscales for QOL related to the body sway test parameters more frequently than cancer survivors (P < .05).Cancer survivors' balance function may have little effect on QOL, unlike in healthy subjects.

The Effects of Chemotherapy-Induced Polyneuropathy on Postural Balance

While cancer prevalence and survival rates are increasing, cancer-treatment-related functional decline and decreased quality of life are on the rise. Adverse side effects such as polyneuropathy are commonly associated with neurotoxic chemotherapeutic agents (i.e., taxanes or platinums) resulting in a decrease in postural balance and an increased risk for falls. This case report highlights an adult with polyneuropathy who received five months of chemotherapy treatment for a breast cancer diagnosis. Measurements included sensory integration of balance control using the BTrackS modified Clinical Test of Sensory Integration and Balance (mCTSIB) protocol and the Timed Up and Go (TUG) test. Compared to normative data, the participant demonstrated poor balance control in all conditions. Specifically, the results indicated proprioception was the most compromised component of balance control. The participant also demonstrated a slower TUG time compared to women of similar age. Our findings highlight the value of quantitative assessment of balance control following chemotherapy. More research would be needed to further support the tailored therapeutic approaches to prevent falls following chemotherapy treatment.

Exercise training improves postural steadiness in cancer survivors undergoing chemotherapy

BACKGROUND

Cancer and cancer treatments negatively affect somatosensory, vestibular, and visual inputs that regulate postural stability and balance, increasing the risk of falling. Exercise training has been shown to mitigate other negative side effects of cancer treatments, such as reducing peripheral neuropathy.

RESEARCH QUESTION

How does 12 weeks of supervised exercise training influence postural stability in cancer survivors who receive chemotherapy?

METHODS

Postural stability of cancer survivors (n = 25; mass = 79.0 ± 22.6 kg; height = 1.66 ± 0.08 m; age = 61 ± 10 years) receiving chemotherapy was assessed prior to and following a 12-week individualized exercise training program by quantifying changes in center of pressure data. A series of 2-factor (pre/post x condition) analysis of variance with repeated measures were used to identify differences between conditions and pre- and post- training program on time and frequency domain measures.

RESULTS

Mediolateral root mean square excursion (p = 0.040; es = 0.20) and resultant mean frequency (p = 0.044; es = 0.29) of the center of pressure trajectory were found to be significantly different between pre- and post-training program. Further, participants dealt better with perturbations after completing the training program by reducing mediolateral root mean square excursion and 95 % confidence ellipse when visual stimulus was removed.

SIGNIFICANCE

Supervised exercise training in cancer patients undergoing chemotherapy improves postural stability in the mediolateral direction. Given that mediolateral movement of the center of pressure has previously been associated with fallers in other populations, exercise training during cancer treatments may be beneficial.

A review of movement disorders in chemotherapy-induced neurotoxicity

Chemotherapy agents used in the standard treatments for many types of cancer are neurotoxic and can lead to lasting sensory and motor symptoms that compromise day-to-day movement functions in cancer survivors. To date, the details of movement disorders associated with chemotherapy are known largely through self-reported symptoms and functional limitations. There are few quantitative studies of specific movement deficits, limiting our understanding of dysfunction, as well as effective assessments and interventions. The aim of this narrative review is to consolidate the current understanding of sensorimotor disabilities based on quantitative measures in cancer survivors who received chemotherapy. We performed literature searches on PubMed and found 32 relevant movement studies. We categorized these studies into three themes based on the movement deficits investigated: (1) balance and postural control; (2) gait function; (3) upper limb function. This literature suggests that cancer survivors have increased postural sway, more conservative gait patterns, and suboptimal hand function compared to healthy individuals. More studies are needed that use objective measures of sensorimotor function to better characterize movement disabilities and investigate the underlying causes, as required for developing targeted assessments and interventions. By updating our understanding of movement impairments in this population, we identify significant gaps in knowledge that will help guide the direction of future research.

Wearable Health Technology to Quantify the Functional Impact of Peripheral Neuropathy on Mobility in Parkinson's Disease: A Systematic Review

The occurrence of peripheral neuropathy (PNP) is often observed in Parkinson’s disease (PD) patients with a prevalence up to 55%, leading to more prominent functional deficits. Motor assessment with mobile health technologies allows high sensitivity and accuracy and is widely adopted in PD, but scarcely used for PNP assessments. This review provides a comprehensive overview of the methodologies and the most relevant features to investigate PNP and PD motor deficits with wearables. Because of the lack of studies investigating motor impairments in this specific subset of PNP-PD patients, Pubmed, Scopus, and Web of Science electronic databases were used to summarize the state of the art on PNP motor assessment with wearable technology and compare it with the existing evidence on PD. A total of 24 papers on PNP and 13 on PD were selected for data extraction: The main characteristics were described, highlighting major findings, clinical applications, and the most relevant features. The information from both groups (PNP and PD) was merged for defining future directions for the assessment of PNP-PD patients with wearable technology. We established suggestions on the assessment protocol aiming at accurate patient monitoring, targeting personalized treatments and strategies to prevent falls and to investigate PD and PNP motor characteristics.

Assessing Postural Stability Using Coupling Strengths between Center of Pressure and Its Ground Reaction Force Components

The center of pressure (COP), which is defined as the point at which the resultant ground reaction force (GRF) is applied on a body, provides valuable information for postural stability assessment. This is because the fundamental goal of balance control is to regulate the center of mass (COM) of the human body by adaptively changing the position of the COP. By using Newtonian mechanics to develop two equations that relate the two-dimensional COP coordinates to the GRF components, one can easily determine the location of the COP using a force plate. An important property of these two equations is that for a given COP position, there exists an infinite number of GRF component combinations that can satisfy these two equations. However, the manner in which a postural control system deals with such redundancy is still unclear. To address this redundancy problem, we introduce four postural stability features by quantifying the coupling strengths between the COP coordinates and their GRF components. Experiments involving younger (18–24 years old) and older (65–73 years) participants were conducted. The efficacy of the proposed features was demonstrated by comparing the differences between variants of each feature for each age group (18–24 and 65–73 years). The results demonstrated that the coupling strengths between the anterior–posterior (AP) direction coordinate of the COP and its GRF components for the older group were significantly higher than those of the younger group. These experimental results suggest that (1) the balance control system of the older group is more constrained than that of the younger group in coordinating the GRF components and (2) the proposed features are more sensitive to age variations than one of the most reliable and accurate conventional COP features. The best testing classification accuracy achieved by the proposed features was 0.883, whereas the testing classification accuracy achieved by the most accurate conventional COP feature was 0.777. Finally, by investigating the interactions between the COP and its GRF components using the proposed features, we found that that the AP component of the GRF of younger people plays a more active role in balance control than that of the GRF of older people. Based on these findings, it is believed that the proposed features can be used as a set of stability measures to assess the effects on posture stability from various health-related conditions such as aging and fall risk.

Out of balance - Postural control in cancer patients before and after neurotoxic chemotherapy

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a serious side effect deriving from neurotoxic chemotherapeutic agents. The underlying nerve injury can affect proprioception causing impaired postural control, gait difficulties and a higher risk of falling. Overall, the symptoms and functional limitations negatively affect patients' independence and quality of life.

RESEARCH QUESTION

Our objective was to analyze postural control in cancer patients before and after neurotoxic chemotherapy and to compare these data to healthy controls.

METHODS

Participants were 35 cancer patients (PAT) and 35 healthy, one-to-one gender, age, height, and weight matched controls (HMC). Postural control of HMC was tested once, whereas PAT were tested prior to (PAT_pre) and three weeks after completion of neurotoxic chemotherapy (PAT_post). Temporal, spatial and frequency domain measures of the center of pressure (COP) were calculated using a force plate. The following balance conditions were analyzed: bipedal stance with open (BP_EO) and closed eyes (BP_EC), semi-tandem (ST_EO, ST_EC) and monopedal stance (MP_EO). CIPN was assessed clinically (Total Neuropathy Score) and via questionnaire. Time and group differences were determined by using Wilcoxon-signed-rank tests. Spearman correlation was applied to analyze associations between severity of CIPN and postural control.

RESULTS

PAT_post showed significantly increased temporal and spatial measures of the COP (p < .05) - both after neurotoxic chemotherapy (PAT_pre-PAT_post) and in comparison to HMC. Withdrawal of visual control resulted in greater temporal and spatial COP displacements in PAT_post than in the comparative groups (PAT_pre, HMC). Correlation analyzes revealed moderate associations of COP measures with clinical CIPN measures and low to none for the questionnaires.

SIGNIFICANCE

Three weeks after completion of neurotoxic chemotherapy, PAT_post showed significant balance deficits compared to PAT_pre and HMC. Especially the deficits in the standing conditions with closed eyes may indicate an impaired proprioception. This hypothesis is supported by the finding that stronger CIPN symptoms were associated with poorer postural control. However, future studies need to take further influencing factors on postural control into account (e.g. strength) in order to generate efficacious rehabilitation measures.

Partnered, adapted argentine tango dance for cancer survivors: A feasibility study and pilot study of efficacy

BACKGROUND

Neurotoxic cancer treatments can cause chemotherapy-induced peripheral neuropathy and postural control deficits that cancer survivors report as a concern. Exercise-based sensorimotor training has emerged as a promising treatment for symptoms including balance deficits, however, more study is needed to optimize engagement and participation. We evaluated feasibility, satisfaction, and preliminary efficacy of a novel balance training program for cancer survivors: partnered, Adapted Argentine Tango dance (Tango).

METHODS

Twenty-two individuals participated (n = 22). Tango classes (1 h) were offered twice/week. At baseline, midpoint (8 classes), and conclusion of the training (15 or 16 classes), we assessed postural control by measuring center-of-pressure (CoP) measures during quiet standing with eyes closed. We also documented attendance, barriers to attendance, and satisfaction (7 point scale; 1 high). At conclusion, we analyzed whether 1) attendance and satisfaction met feasibility criteria; 2) postural control improved among participants who were outside of normal range at baseline; and 3) co-enrolling with a companion increased attendance.

FINDINGS

Feasibility criteria were met: more than half of participants attended more than half the classes offered with a mean satisfaction rate of 1.2 (SD 0.4). Those who enrolled with a companion (n = 9) attended more sessions than those who did not (n = 13) (Mann-Whitney U value = 20; p = 0.012). Participants with demonstrated deficits (n = 9) improved in 3 CoP measures at midpoint (i.e., medial-lateral sway, ellipse area, medial-lateral velocity), retaining improvement in 2 CoP measures at endpoint (i.e., medial-lateral sway, ellipse area).

INTERPRETATION

Partnered, Adapted Argentine Tango is feasible for cancer survivors and may improve postural control. Enrolling with a companion improved attendance.

Assessment of the Mini-Balance Evaluation Systems Test, Timed Up and Go test, and body sway test between cancer survivors and healthy participants

BACKGROUND

Cancer survivors experience late and long-term effects of treatment; also, the disease itself might be responsible for persisting functional impairments. The purpose of this study was to investigate muscle strength, balance function using the Mini-Balance Evaluation Systems Test and Timed Up and Go test with single and cognitive dual tasks and body sway in breast cancer survivors and healthy women and non-breast cancer survivors and healthy participants.

METHODS

Twenty-six cancer survivors and 19 healthy participants were assessed for grip and knee extension strength with the Mini-Balance Evaluation Systems Test, Timed Up and Go, and body sway test performance.

FINDINGS

Breast cancer survivors had significantly lower hand grip strength (p < .05) and Mini-Balance Evaluation Systems Test scores than healthy women (p < .05). Additionally, in breast cancer survivors, hand grip strength had a significant relationship with Mini-Balance Evaluation Systems Test and Timed Up and Go scores (p < .05) but had no relationship with the total center of pressure length. Hand grip strength and Mini-Balance Evaluation Systems Test scores were not significantly different in non-breast cancer survivors and healthy participants. In non-breast cancer survivors, knee extension strength had a significant relationship with the Timed Up and Go scores (p < .05).

INTERPRETATION

The relationship between muscle strength and balance function may be characterized by the different diagnoses in cancer survivors. The current findings showed the changes in balance function and muscle strength among cancer survivors.

Gait variability is altered in cancer survivors with self-reported neuropathy

BACKGROUND

Falls are prevalent among cancer survivors, and neuropathy, a side effect from chemotherapy treatment, is thought to contribute to falls. While falls commonly occur during walking, there is limited information about gait function in cancer survivors with neuropathy.

RESEARCH QUESTION

What is the difference between gait speed and gait variability in cancer survivors with and without self-reported neuropathy and healthy controls?

METHODS

Seventeen cancer survivors and 12 healthy individuals [age: 53.5 (11.8), gender: 10 females] participated in a single testing session. Cancer survivors were grouped into neuropathy [n = 9; age: 61.9 (6.1); gender: 8 females] and no neuropathy [n = 8; age: 50.75 (14.1); gender: 7 females] based on the self-reported FACT/GOG Neurotoxicity subscale questionnaire. All participants completed two walking trials at their comfortable pace across a 6 m pressure sensitive walkway. A one-way ANOVA with Tukey's post-hoc analysis and effect sizes were used to detect differences in gait speed, step length variability, and step width variability between groups.

RESULTS

Although there were no group differences in gait speed, a significant main effect was found for step length variability (p =  0.03, η² = 0.24) between groups. Step length variability was significantly less in cancer survivors with neuropathy than healthy controls (p = 0.05, d = 1.30). There was a significant main effect for step width variability between groups (p = 0.05, η² = 0.20). Cancer survivors with neuropathy had significantly greater step width variability than healthy controls (p = 0.04, d = 1.04).

SIGNIFICANCE

Cancer survivors with neuropathy display greater step width variability and less step length variability than healthy controls. Gait variability may be a more sensitive marker than gait speed to track mobility in cancer survivors with neuropathy symptoms. Assessing and treating gait function in cancer survivors with neuropathy symptoms may improve everyday ambulation.

Postural sway, falls, and self-reported neuropathy in aging female cancer survivors

BACKGROUND

Falls are a major public health concern in older adults, and the proportion of older adults that has been diagnosed with cancer is growing. Yet, while falls, peripheral neuropathy, and postural instability are more common in aging cancer survivors, it is unclear how these factors interact.

RESEARCH QUESTION

Our objective was to examine how components of sway related to self-reported neuropathy and falls.

METHODS

Postural sway during static stance was recorded with an inertial sensor (APDM Opal), placed on the lumbar spine region in 434 older female cancer survivors (mean age 63) and 49 healthy older female control subjects (mean age 63). Measures of sway were resolved into principal components that were compared between women with and women without self-reported falls in the previous 6 months and between those with and without self-reported symptoms of peripheral neuropathy.

RESULTS

Cancer survivors had worse sway than healthy control subjects in components related to sway magnitude and mediolateral frequency of sway, but no difference in the component related to resultant / AP sway jerk and frequency. Cancer survivors who reported neuropathy were more likely to have higher resultant / AP sway frequencies and jerk than asymptomatic survivors, while survivors who reported a fall were more likely to have lower frequencies of mediolateral sway than non-fallers. Falls were more strongly associated with mediolateral sway in survivors with more severe neuropathy; whereas falls were more strongly associated with resultant / AP sway frequency in survivors with less severe neuropathy SIGNIFICANCE: Postural stability, falls, and neuropathy have complex interactions that can vary across components of postural sway. While the frequency of mediolateral sway was associated with falls across our entire cohort, neuropathy influenced the associations between specific characteristics of sway and falls, which may have implications for fall prevention interventions.

Gait and Balance Impairments in Breast Cancer Survivors: A Systematic Review and Meta-analysis of Observational Studies

Objective

To systematically review and quantitatively synthesize gait and balance impairments in breast cancer survivors compared with age-matched controls or normative values for adults who never had breast cancer.

Data Sources

PubMed, Cumulative Index of Nursing and Allied Health, and Web of Science was searched using terms associated with breast cancer, mobility, and adult until November 2018.

Study Selection

Studies were included if they were randomized control trials, cross-sectional, prospective, pre-post, or case-control by design, included adult breast cancer survivors, reported gait and/or balance metrics as primary or secondary outcomes, were peer-reviewed publications, and were written in English. The search yielded 2117 results with 29 studies meeting the inclusion criteria.

Data Extraction

Two reviewers assessed study quality by the National Institutes of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies to determine the strength of evidence for each study that met the inclusion criteria. Basic descriptors of each study, study protocol, and balance and gait measures were extracted. Meta-analysis was performed for the single leg stance, functional reach, center of pressure velocity, gait speed, and timed up and go.

Data Synthesis

For quality assessment, 3 studies were rated good, 16 fair, and 10 poor. The meta-analysis indicated that there were no significant differences in single leg stance between breast cancer survivors and those who never had breast cancer (P=.33). Pooled values of the functional reach task (22.16cm; 95% CI, 8.98-35.33) and center of pressure velocity (1.2cm/s; 95% CI, 0.87-1.55) suggest balance impairment in breast cancer survivors when compared with normative values. Breast cancer survivors also performed worse than those who never had breast cancer in challenging balance conditions that reduced sensory information or altered base of support. Pooled gait speed at a usual speed (0.91m/s; 95% CI, 0.2-1.6), fast speed across a short distance (1.2m/s; 95% CI, 0.31-2.1), and fast gait speed across a long distance (1.65m/s; 95% CI, 1.64-1.66) suggest gait impairments when compared with normative values.

Conclusions

Breast cancer survivors may demonstrate gait and balance impairments compared with normative values. Clinicians should consider assessing changes in balance and gait in breast cancer survivors to improve functional independence and prevent fall-related injuries.

Impaired Postural Control and Altered Sensory Organization During Quiet Stance Following Neurotoxic Chemotherapy: A Preliminary Study

Individuals diagnosed with chemotherapy-induced peripheral neuropathy (CIPN) demonstrate impaired balance and carry an increased risk of falling. However, prior investigations of postural instability have only compared these individuals against healthy controls, limiting the understanding of impairments associated with CIPN. Therefore, the purpose of this study was to better isolate postural control impairments that are associated with CIPN. Twenty cancer survivors previously diagnosed with breast or colorectal cancer participated. Participants were separated into 3 groups: no prior chemotherapy exposure (CON, n = 6), and recent treatment with taxane- or oxaliplatin-based chemotherapy with no/mild symptoms of CIPN (-CIPN, n = 8) or moderate/severe symptoms of CIPN (+CIPN, n = 6). Postural control was assessed by measuring center of pressure during standing balance conditions that systematically interfered with somatosensory, visual, and/or vestibular information. The presence of CIPN sensory symptoms was associated with impaired postural control, particularly during eyes-closed balance conditions ( P < .05). Additionally, medial-lateral postural instability was more pronounced in the +CIPN group compared with the -CIPN group and CON participants ( P < .05). Greater postural instability during eyes-closed balance in individuals with CIPN is consistent with impaired peripheral sensation. Balance impairments in cancer survivors with CIPN demonstrate the unique challenges in this population and motivate the need for targeted efforts to mitigate postural control deficits that have previously been associated with fall risk.

Differences in Balance Function Between Cancer Survivors and Healthy Subjects: A Pilot Study

Older adults who have survived cancer experience significantly more falls compared with healthy adults. Adult cancer survivors may also have a lower balance function than healthy adults. We examined muscle strength and balance function among 19 cancer survivors and 14 healthy subjects. The mean age of the cancer survivors was 51.5 ± 11.2 years; 6 men and 13 women. Cancer diagnoses included breast cancer, retroperitoneal sarcoma, acute leukemia, lung cancer, colorectal cancer, thyroid cancer, Ewing’s sarcoma, and tongue cancer. The mean age of healthy subjects was 47.4 ± 14 years; 3 men, 11 women. Muscle strength was assessed using hand grip and knee extensor strength tests. Balance function was evaluated using the Timed Up and Go (TUG) test, and body sway was tested using a force platform. No significant differences were found with respect to right and left grip strength or right and left knee extension strength between the 2 groups. A significantly higher TUG time was observed in cancer survivors than in healthy subjects (P < .05). With eyes open, the area of the center of pressure was significantly larger in cancer survivors than in healthy subjects (P < .05). Similarly, the length per area was significantly lower both with eyes open and closed for cancer survivors than for healthy subjects (P < .05). TUG was significantly correlated with muscle strength in both groups (P < .05). However, no body sway parameters were related to muscle strength in either group. Cancer survivors had lower balance function that might not have been related to muscle strength. Cancer survivors should be evaluated for balance function as there is a potential for impairment. The findings of this study will be relevant for planning the prevention of falls for cancer survivors.

SeeSway - A free web-based system for analysing and exploring standing balance data

BACKGROUND AND OBJECTIVES

Computerised posturography can be used to assess standing balance, and can predict poor functional outcomes in many clinical populations. A key limitation is the disparate signal filtering and analysis techniques, with many methods requiring custom computer programs. This paper discusses the creation of a freely available web-based software program, SeeSway (www.rehabtools.org/seesway), which was designed to provide powerful tools for pre-processing, analysing and visualising standing balance data in an easy to use and platform independent website.

METHODS

SeeSway links an interactive web platform with file upload capability to software systems including LabVIEW, Matlab, Python and R to perform the data filtering, analysis and visualisation of standing balance data. Input data can consist of any signal that comprises an anterior-posterior and medial-lateral coordinate trace such as center of pressure or mass displacement. This allows it to be used with systems including criterion reference commercial force platforms and three dimensional motion analysis, smartphones, accelerometers and low-cost technology such as Nintendo Wii Balance Board and Microsoft Kinect. Filtering options include Butterworth, weighted and unweighted moving average, and discrete wavelet transforms. Analysis methods include standard techniques such as path length, amplitude, and root mean square in addition to less common but potentially promising methods such as sample entropy, detrended fluctuation analysis and multiresolution wavelet analysis. These data are visualised using scalograms, which chart the change in frequency content over time, scatterplots and standard line charts. This provides the user with a detailed understanding of their results, and how their different pre-processing and analysis method selections affect their findings.

RESULTS

An example of the data analysis techniques is provided in the paper, with graphical representation of how advanced analysis methods can better discriminate between someone with neurological impairment and a healthy control.

CONCLUSIONS

The goal of SeeSway is to provide a simple yet powerful educational and research tool to explore how standing balance is affected in aging and clinical populations.