Monaural and binaural galvanic vestibular stimulation in human dynamic balance function

Spontaneous dynamic balance reactions to galvanic binaural and monaural stimulation were investigated in lateral sway. Low-intensity currents were used to stimulate the vestibular apparatus of subjects, who were standing with their eyes closed on a rocking platform. Head and body base movements were measured in the lateral plane, simultaneously. In monaural as well as in binaural stimulation mode, the onset of the current induced a lateral biphasic stereotyped postural responses: firstly the pressure centre moved towards the cathode side then the whole body swayed towards the anode side. The cut-off of the current resulted in a similar pattern of movement but in the opposite direction. Two main features characterised the response obtained in monaural mode. First, the amplitude of the dynamic balance response was half the size of that recorded in binaural stimulation mode. Second, cathodal monaural stimulation on one side or anodal monaural stimulation on the opposite side elicited superimposable responses. The results demonstrate that in healthy subjects, postural response to binaural galvanic vestibular stimulation results from the linear sum of two equivalent stimulations: one from the cathodal excitation and the other from the anodal inhibition. The method could be used in clinical studies to detect vestibular asymmetries and dysfunction.     

Prevalence of hydrocephalus in 157 patients with vestibular schwannoma

The purpose of this study was to determine the prevalence of hydrocephalus in patients with vestibular schwannoma. A second objective was to investigate possible etiologies for hydrocephalus in this population by attempting to correlate the incidence and severity of hydrocephalus with tumor volume and extent of fourth ventricular compression. The MRI examinations of 157 adult patients with vestibular schwannoma were retrospectively reviewed. Tumor size was quantified, and the presence of accompanying hydrocephalus was assessed, categorized as communicating type or non-communicating type and then rated as mild, moderate or severe (grades 1–3). Next, the degree of fourth ventricular distortion caused by tumor mass effect was evaluated and categorized as mild, moderate or severe (grades 1–3). Spearmans rank correlation coefficient was used to test the relationships between tumor volume and (1) the extent of fourth ventricular effacement and (2) severity of hydrocephalus. Hydrocephalus was present in 28/157 (18%) cases and was categorized as mild in 11/28 (39%), moderate in 15/28 (54%) and severe in 2/28 (7%). Communicating-type hydrocephalus was present in 17/28 (61%) and non-communicating type in 11/28 (39%). There was a positive correlation between the grade of non-communicating hydrocephalus and tumor volume (r=0.38; P<0.001) and between the severity of fourth ventricular compression and extent of hydrocephalus in this group(r=0.43; P<0.001). In patients who were classified as having communicating hydrocephalus, the correlation between tumor volume and the severity of hydrocephalus was poor (r=0.19; P=0.02) as was the correlation between the extent of fourth ventricular distortion and the severity of hydrocephalus (r=0.21; P<0.01). There is a high prevalence of hydrocephalus in patients with vestibular schwannoma. In a minority of cases non-communicating type hydrocephalus is present and the severity of hydrocephalus can be attributed to the affect of tumor volume on fourth ventricular compression. More commonly, however, communicating-type hydrocephalus exists and the correlation between the severity of fourth ventricular compression and extent of hydrocephalus is poor. Therefore, other etiologies for hydrocephalus, such as tumor protein sloughing, are likely relevant.     

Interference between walking and a cognitive task is increased in patients with bilateral vestibular loss

The aim of this study was to determine whether there is more deterioration in walking under dual-task conditions in patients with bilateral vestibular loss (BVL) than in healthy subjects, as opposed to the findings after unilateral loss. For this purpose, 12 patients with BLV and 12 healthy control subjects performed 3 tasks: walking along a 10-m walkway, counting backwards by two, and both tasks simultaneously. Patients did not differ from controls in their walking speed in the single task condition, or in their cognitive performance in both the single and dual-task conditions. However, walking performance was more affected in patients than in controls under dual-task conditions, as shown by slower gait speed in the dual-task, higher reduction in gait speed from single to dual-task, and lower global dual-score. These findings provide evidence for greater attentional interference between walking and counting in patients with BVL.     

大前庭导水管综合征内淋巴囊和前庭导水管MRI信号特征及其临床意义

目的 探讨大前庭导水管综合征患者内淋巴囊和前庭导水管MRI信号特征及其与听力损失的关系.方法 搜集大前庭导水管综合征31例共62只内耳的MRI和听力资料.MRI表现分4型:I型的内淋巴囊及前庭导水管裂隙范围内均为低信号区,无高信号区;Ⅱ～Ⅳ型除低信号区外,还可见高信号区;Ⅱ型的高信号区局限于前庭导水管裂隙内;Ⅲ型的高信号区自前庭导水管裂隙向后超出岩骨后缘,但其下界在后半规管下脚平面以上,在平面以下者为Ⅳ型.为避免肉眼观察误差,测量内淋巴囊高信号区、低信号区和前庭的信号强度,并与同层脑脊液信号强度比较.采用配对t检验分析内淋巴囊高信号区与低信号区、前庭之间信号强度的差异,纠正卡方检验,用Spearman分析判断内淋巴囊MRI分型与听力损失程度的相关性.结果 31例共62耳中Ⅰ型10耳(听力下降为中度1耳,重度4耳,极重度5耳);Ⅱ型17耳(听力下降为中度1耳,重度5耳,极重度11耳);Ⅲ型23耳(听力下降为中度3耳,重度5耳,极重度15耳);Ⅳ型12耳(听力下降为轻度1耳,中度1耳,重度3耳,极重度7耳).高信号区与同层脑脊液信号强度的比值为0.95 ±0.12,低信号区为0.49±0.10,前庭为0.99±0.08,高、低信号区分界清楚,信号比值为2.02±0.06.高、低信号区间信号强度差异有统计学意义(t=- 24.966,P＜0.05),高信号区与前庭的信号差异无统计学意义(t=-24.966,P＞0.05).不同MRI分型对应的听力损失差异无统计学意义(似然比值为5.02,P＞0.05),高、低信号区强度比值与听力损失无相关性(r=0.135,P=0.297).结论 大前庭导水管综合征不只是内淋巴囊扩大,也可以伴有外淋巴液疝入前庭导水管骨性裂隙中;内淋巴囊MRI信号特征与听力损失程度之间未见相关.     

Validity and reliability of video analysis to evaluate ankle proprioceptive reintegration during postural control

BackgroundThe ability to dynamically reintegrate proprioceptive signals after they have been perturbated is impaired in certain pathologies. Evaluation of proprioceptive reintegration is useful for clinical practice but currently requires expensive laboratory tools. We developed a simple method, accessible to clinicians.Research question: Is two-dimensional (2D) video analysis of earlobe displacement a valid and reliable tool for the evaluation of ankle proprioceptive reintegration following muscle vibration?MethodsThirty-eight healthy individuals underwent vibration of the triceps surae while standing on a force plate (FP). Anterior (sagittal plane) earlobe displacement (‘overshoot’) was recorded at vibration cessation using 2D video analysis and rated by 3 blind examiners. Correlation analysis was performed between earlobe and center of pressure displacement (dCoP, recorded with the FP) to determine validity. Intra and interrater reliability were determined by calculation of the intraclass correlation coefficient (ICC), change in the mean (CiM), standard error of measurement (SEM) and the minimal detectable change (MDC).Results and significanceStrong positive correlations (r = 0.82–0.94, p < .001) were found between video and FP data. Intra- and interrater reliability were excellent (ICC from 0.99 to 1.00 and from 0.90 to 0.97 respectively). For intrarater analysis, the CiM was 0.01 cm, SEM were 0.27 cm (95% CI: 0.23–0.33) and 3.43% (95% CI: 2.92–4.20) and the MDC was 0.74 cm. For interrater reliability, the CiM ranged from − 0.81–0.55 cm, the SEM from 0.61 to 1.12 cm and the MDC from 1.69 to 3.10 cm. 2D video analysis of anterior (sagittal) earlobe displacement is therefore a valid and reliable method to assess postural recovery following muscle vibration. This simple method could be used by clinicians to evaluate the ability of the central nervous system to reintegrate proprioceptive signals from the ankle. Further studies are needed to assess its validity in individuals with proprioceptive impairment.     

Short-term retention effect of rehabilitation using head position-based electrotactile feedback to the tongue: Influence of vestibular loss and old-age

Our objective was to evaluate whether the severity of vestibular loss and old-age (>65) affect a patient's ability to benefit from training using head-position based, tongue-placed electrotactile feedback. Seventy-one chronic dizzy patients, who had reached a plateau with their conventional rehabilitation, followed six 1-h training sessions during 4 consecutive days (once on days 1 and 4, twice on days 2 and 3). They presented bilateral vestibular areflexia (BVA), bilateral vestibular losses (BVL), unilateral vestibular areflexia or unilateral vestibular losses and were divided into two age-subgroups (≤65 and >65). Posturographic assessments were performed without the device, 4 h before and after the training. Patients were tested with eyes opened and eyes closed (EC) on static and dynamic (passively tilting) platforms. The studied posturographic scores improved significantly, especially under test conditions restricting either visual or somatosensory input. This 4-h retention effect was greater in older compared to younger patients and was proportional to the degree of vestibular loss, patients with increased vestibular losses showing greater improvements. In bilateral patients, who constantly fell under dynamic-EC condition at the baseline, the therapy effect was expressed by disappearance of falls in BVL and significant prolongation in time-to-fall in BVA subgroups.Globally, our data showed that short training with head-position based, tongue-placed electrotactile biofeedback improves balance in chronic vestibulopathic patients some 16.74% beyond that achieved with standard balance physiotherapy. Further studies with longer use of this biofeedback are needed to investigate whether this approach could have long-lasting retention effect on balance and quality of life.     

Anticipatory activation of postural muscles associated with bilateral arm flexion in subjects with different quiet standing positions

We investigated changes in activation timing and magnitude of the postural muscles according to initial standing positions. The subjects were divided into three groups depending on the position of the center of foot pressure (CFP) during quiet standing, namely backward, middle, and forward. Subjects maintained standing postures at various CFP positions in the anteroposterior direction, and then started bilateral arm movement at their own pace. The activation magnitude of the biceps femoris (BF) and erector spinae (ES) did not differ among any of the initial CFP positions. In only the BF, the preceding action to the anterior deltoid (AD) was clearly observed at more forward CFP positions in the order of the forward, middle and backward groups. Between initial CFP positions adjacent to quiet standing posture, the smallest change was observed in the preceding activation time of the BF. Significant correlation was observed between the background activity and activation time in both the BF and ES.     

Compensatory postural responses to backward loss of balance in patients with cerebellar disease

BackgroundImpaired control of balance and coordinated reactions are a primary deficit of cerebellar dysfunction. As compared to other neurological patients with balance impairments, there has been little research assessing the characteristics of compensatory responses associated with falls in patients with cerebellar disease (CD).Research questionThe aim of this study was to examine the effects of cerebellar disease on compensatory balance control in response to postural perturbation. Do CD patients increase the number of steps when responding to instability because of inappropriate initial step reactions or poor control of trunk motion or both?MethodsIn this explorative study, 10 patients suffering from degenerative cerebellar ataxia and 10 age-matched healthy controls were examined. The balance recovery reactions were assessed using a lean-and-release postural perturbation method. Spatiotemporal characteristics of stepping movement and COM variables associated with torso motion were analyzed using 3D motion capture system.ResultsCD patients took multiple steps whereas matched controls generally took single steps to recover balance following perturbation. The characteristics of the initial step at the time of the fall revealed that foot reaction time, foot response time, and step distance of the initial step were similar between CD patients and matched controls. However, CD patients exhibited a shorter foot-to−COM distance, higher COM velocity, and less trunk flexion with which to attenuate their body momentum after the landing of the first step than did matched controls.SignificanceAlthough initial step responses were probably adequate, poor control of torso motion appears to be a particular problem that causes multiple-step reactions in CD patients. This observation would help to guide the development of tailored fall intervention strategies in CD patients aimed at promoting their recovery capacity in response to a pronounced balance challenge.     

Comparison of the reliance of the postural control system on the visual,vestibular and proprioceptive inputs in chronic low back pain patients and asymptomatic participants

BackgroundAlthough proprioception deficits have been documented in chronic low back pain (CLBP) patients, little is known about adaptive strategies to provide postural control in these patients. Substitution of unreliable proprioceptive information with other afferents might be considered plausible.Research questionIs the response of the postural control system dependent on the source of sensory afferents being manipulated in persons with and without CLBP?MethodsSixty persons with and without CLBP participated in this cross-sectional study. Center of pressure (COP) displacement range, velocity, path length and area were calculated under four sensory conditions: 1) normal upright standing; 2) upright standing on a foam with eyes open and head in neutral position; 3) upright standing with eyes open and 60° cervical extension and 4) upright standing with eyes closed and 60° cervical extension. A two-way repeated measures analysis of variance was used to compare COP masseurs under different conditions and between the groups.ResultsCLBP patients demonstrated fewer alterations to manipulation of both visual and vestibular afferents in terms of number of COP variables significantly altered. ML range and velocity in both groups and path length in the CLBP group were significantly different between conditions 2 and 4. In both groups, all COP variables except AP range increased significantly in condition 2 compared to conditions 1and 3 (p < 0.001). AP velocity was the only variable to be different between conditions 1 and 3 in both CLBP (p = 0.025) and control (p < 0.001) groups. Between group differences were significant on AP velocity (p = 0.019).SignificanceNo overweighting was observed in the vestibular or visual afferents in CLBP patients. Compensatory strategies seem to lie within proprioceptive system by reweighting afferents from different body segments. The postural control system behaved more robustly in CLBP patients while AP COP velocity was found as the most sensitive and discriminating parameter.     

Reliability,internal consistency,and concurrent validity of a modified version of the dynamic gait index in people with vestibular disorders

BackgroundPeople with vestibular disorders often have abnormalities in gait and balance. The Dynamic Gait Index (DGI) is a relatively effective clinical gait measure that has been validated for use in patients with vestibular disorders. The modified version of the DGI (M-DGI) is based on the original DGI.Research questionThe objective of this study was to refine and test the clinical application of the M-DGI, and to investigate whether it is an effective indicator of dynamic gait in patients with vestibular disorders.MethodsA reliability and validity study. All raters reviewed the instructions and scoring criteria for each M-DGI item prior to the initial test. The raters simultaneously scored two M-DGI tasks for the 75 subjects, and the two tasks were completed with an interval of two hours in-between. Reliability of total M-DGI scores was assessed using intraclass correlation coefficients (2,1). Internal consistency of the M-DGI was evaluated using Cronbach’s alpha. Concurrent validity of the M-DGI with Dizziness Handicap Inventory (DHI) and Timed “Up & Go” Test (TUG) was assessed using Spearman’s rank order correlation coefficient.Results and SignificanceInterrater and intrarater reliability of the total M-DGI scores were reflected by ICCs of 0.99 and 0.97. Internal consistency of the M-DGI score was 0.9975. Spearman’s rank order correlation coefficient of the M-DGI score with the Dizziness Handicap Inventory (DHI) and the Timed “Up & Go” Test (TUG) was 0.72 and 0.65, respectively.The M-DGI demonstrates acceptable reliability, internal consistency, and concurrent validity for use as a clinical gait measurement for patients with vestibular disorders.     

Immediate effects of real-time postural biofeedback on spinal posture,muscle activity,and perceived pain severity in adults with neck pain

BackgroundPrevious studies have investigated various types of postural biofeedback devices on different body regions to improve posture; however, they focused only on healthy adults without a history of chronic musculoskeletal disorders. In addition, those postural biofeedback devices used in previous studies are often designed for experimental research. The designs are usually bulky with many wires, which is not practical for everyday use.Research questionThe aim of this study was to determine the immediate effect of a commercially available real-time postural biofeedback device on spinal posture, muscle activity, and perceived pain severity in adults with neck pain.Methods21 adults who had chronic or recurrent nonspecific neck pain for more than 3 months and whose pain was induced or aggravated by prolonged computer work were enrolled in this study. Spinal posture (head tilt, neck flexion, cervical and thoracic angles), muscle activity (cervical erector spinae, upper trapezius, and thoracic erector spinae), and self-reported neck and shoulder pain were measured during computer typing tasks, with and without biofeedback.ResultsCompared with the non-biofeedback condition, the biofeedback condition significantly decreased neck flexion, upper cervical, and lower thoracic angles and lowered the activity of the cervical erector spinae. Self-reported neck pain was not influenced by the application of biofeedback, but significantly increased over the 1-hour typing task.SignificanceThe application of a commercially available wearable real-time biofeedback device improves sitting posture and reduces muscular activity in adults with nonspecific neck pain during computer work. Future studies should examine the long-term effects of wearable real-time postural biofeedback devices for prevention and management of neck pain.     

骨科手术机器人与人工置钉治疗股骨颈骨折失血量比较

  目的 探讨骨科手术机器人定位下置钉治疗股骨颈骨折手术对失血的影响,寻找减少手术失血的方法。 方法 收集2016-12至2017-03医院收治的21例行机器人定位下空心钉内固定的股骨颈骨折患者为A组(机器人手术组),选取2016-06至2016-12未使用机器人定位行空心钉内固定的23例股骨颈骨折患者为B组(非机器人手术组),通过收集患者术日晨和术后第1、3、5天晨血常规,对比分析术后第1、3、5天的理论出血量、红细胞压积、血红蛋白量,及患者一般情况。 结果 A组患者术后第1、3天失血量分别为(133±101)ml、(233±78)ml,均小于B组的(302±191)ml、(451±280)ml,两组对比差异均有统计学意义(P＜0.05);A组术后1、3天的血红蛋白分别为(117.13±13.24)g/L、(123.16±12.09)g/L,均高于B组的(112.09±13.25)g/L、(117.31±13.32)g/L,差异均有统计学意义(P＜0.05)。 结论 微创闭合复位空心钉固定治疗股骨颈骨折,使用机器人定位下进行手术,定位精准,术中穿刺次数减少,减少了手术的出血,值得临床推荐。     

Association between sensorimotor function and visual assessment of postural orientation in patients with ACL injury

ObjectivesTo investigate the association between sensorimotor function and visual assessment of postural orientation during execution of weight-bearing activities in patients with anterior cruciate ligament reconstruction (ACLR).DesignCross-sectional study.SettingLaboratory.ParticipantsFifty-two individuals (23 women and 29 men, mean (SD) age 26.5 (6.4)) approximately 7 months after ACLR.Main outcome measuresSensorimotor function (proprioception, ankle dorsiflexion range of motion, and isometric muscle strength of the hip, knee, and trunk) were recorded on the injured leg. Postural orientation errors (POEs) were visually scored from video-recordings of the injured leg during execution of 5 functional tasks, and POE subscales activities of daily living (ADL) and Sport, and Total POE score were used in the analysis.ResultsLower hip external rotation strength was associated with higher Total POE score (B = −24.4, p = 0.041) and higher POE subscale ADL score (B = −24.9, p = 0.03). No associations between sensorimotor function and POE subscale Sport were found.ConclusionsDecreased hip external rotation strength might contribute to higher scores on the POE subscale ADL and the Total POE score, in men and women following ACLR. Future studies will reveal if strengthening of hip external rotation strength improves postural orientation.     

Comparative analysis of blood loss and haemodynamic changes in endoprosthesis replacing of coxofemoral joint in patients with bilateral coxarthrosis

Comparative analysis of blood loss and haemodynamic changes in endoprosthesis replacing of coxofemoral joint in patients with bilateral coxarthrosis. Endoprosthesis replacement of coxofemoral joint is the method of choice in treatment of bilateral coxarthrosis which can eliminate the pain syndrome and physical restraint of patients. Also this method gives the opportunity for fast return to the labor activity. However, this orthopedic device is related to the different complications, the most dangerous among them is the blood loss. The method of the single-stage bilateral endoprosthesis replacement of coxofemoral joint was developed and introduced in the center of traumatology and orthopedics of the Central Military Clinical Hospital n.a N.N.Burdenko. The offered method let to reduce the total intraoperative blood loss at average to 30% in comparison with the consequential surrogation of two coxofemoral joint.     

Posture and balance control in patients with acromegaly: Results of a cross-sectional study

Acromegaly is a chronic debilitating disease that presents with multiple systemic manifestations, including changes in body composition, joint abnormalities, muscular impairment and visual disturbances. This study aimed to assess posture and body balance in acromegalic patients and to establish the correlation between these measures. Twenty-eight acromegalic patients and a similar number of control subjects matched for sex, age, weight, height and body mass index underwent postural evaluation using the photogrammetry and measurement of balance using the stabilometry in two tasks: feet apart, eyes open and feet together, eyes closed. In comparison with the control group, the acromegalic group presented postural deviations in lateral views in the vertical alignment of the trunk (P = 0.001 for the right side and P = 0.021 for the left), the hip angle (P = 0001 for the right side and P = 0.016 for the left side) and horizontal alignment of the pelvis (P = 0.017 for the right and P < 0.001 for the left side). Compared with healthy subjects, the acromegalic patients presented displacement of the centre of pressure in both the anterior–posterior direction and the medial–lateral direction in both evaluated tasks. We observed significant correlations between balance measures and the following posture evaluation variables: distance between the lower limbs, horizontal alignment of the head and vertical alignment of the head. Our results suggest that posture and balance need to be evaluated for acromegalic patients in clinical practice, as there are significant postural imbalances and deviations in these patients.     

Between-day reliability of triceps surae responses to standing perturbations in people post-stroke and healthy controls: A high-density surface EMG investigation

The reliability of triceps surae electromyographic responses to standing perturbations in people after stroke and healthy controls is unknown. High-Density surface Electromyography (HDsEMG) is a technique that records electromyographic signals from different locations over a muscle, overcoming limitations of traditional surface EMG such as between-day differences in electrode placement. In this study, HDsEMG was used to measure responses from soleus (SOL, 18 channels) and medial and lateral gastrocnemius (MG and LG, 16 channels each) in 10 people after stroke and 10 controls. Timing and amplitude of the response were estimated for each channel of the grids. Intraclass Correlation Coefficient (ICC) and normalized Standard Error of Measurement (SEM%) were calculated for each channel individually (single-channel configuration) and on the median of each grid (all-channels configuration). Both timing (single-channel: ICC = 0.75–0.96, SEM% = 5.0–9.1; all-channels: ICC = 0.85–0.97; SEM% = 3.5–6.2%) and amplitude (single-channel: ICC = 0.60–0.91, SEM% = 25.1–46.6; ICC = 0.73–0.95, SEM% = 19.3–42.1) showed good-to-excellent reliability. HDsEMG provides reliable estimates of EMG responses to perturbations both in individuals after stroke and in healthy controls; reliability was marginally better for the all-channels compared to the single-channel configuration.     

An evaluation of adaptive planning by assessing the dosimetric impact of weight loss throughout the course of radiotherapy in bilateral treatment of head and neck cancer patients

The purpose of this study was to investigate the dosimetric impact of weight loss in head and neck (H&N) patients and examine the effectiveness of adaptive planning. Data was collected from 22 H&N cancer patients who experienced weight loss during their course of radiotherapy. The robustness of Intensity Modulated Radiation Therapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) treatment plans were compared including the potential need for replanning. The dosimetric impact of weight loss was evaluated by calculating a verification plan for each patient on an assessment CT scan taken during the course of treatment. Using a regression analysis, significance was tested for the dosimetric change in target volumes and 10 specific organs at risk (OAR) using an anatomical separation difference in the H&N at corresponding levels. For both the IMRT and VMAT plans, a significant correlation was found for the dose to 5% of the high risk Planning Target Volume (PTV) (D₅), dose to 95% of the intermediate risk PTV and Clinical Target Volume (CTV) (D₉₅), and the percentage of the pharynx receiving 65 Gy. An independent t-test was also performed for each metric in the VMAT and IMRT plans showing the dose to 95% of the intermediate risk PTV as significant. No quantitative method for finding the threshold of anatomical separation difference requiring a replan was established. Based on the increase in dose to organs at risk and increased target coverage due to separation loss, it was concluded that adaptive radiotherapy may not always be necessary when alignment of bony anatomy and remaining soft tissue is within tolerance. Physician judgment and preference is needed in such situations.     

Associations of self-report measures with gait,range of motion and proprioception in patients with lumbar spinal stenosis

IntroductionSpinal stenosis is defined as neurogenic claudication due to narrowing of the spinal canal lumen diameter. As the disease progresses, ambulation and gait may be impaired. Self-report measures are routinely used in the clinical setting to capture data related to lumbar pain symptoms, function and perceived disability. The associations between self-report measures and objective measures of physical function in patients with lumbar spinal stenosis are not well characterized. The purpose of this study was to determine the correlation between self-reported assessments of function with objective biomechanical measures of function.Methods25 subjects were enrolled in this study. Subjects completed self-report questionnaires and biomechanical assessments of gait analysis, lumbar 3D ROM and lumbar proprioception. Correlations were determined between self-report measures and biomechanical data.ResultsThe Oswestry Disability Index (ODI) was strongly correlated with stride length and gait velocity and weakly correlated with base of support. ODI was also weakly correlated with left lateral bending proprioception but not right lateral bending. The SF12 was not significantly correlated with any of the biomechanical measurements. Pain scores were weakly correlated with velocity, and base of support, and had no correlation any of the other biomechanical measures.DiscussionThere is a strong correlation between gait parameters and functional disability as measured with the ODI. Quantified gait analysis can be a useful tool to evaluate patients with lumbar spinal stenosis and to assess the outcomes of treatments on this group of patients.     

USPIO-enhanced magnetic resonance imaging for nodal staging in patients with head and neck cancer

PURPOSE: To determine the accuracy of ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI) for nodal staging in patients with head and neck cancer. MATERIALS AND METHODS: Twenty patients with carcinomas of the upper aerodigestive tract were prospectively enrolled. MRI was performed before and 24-36 hours after intravenous infusion of an USPIO agent, ferumoxtran-10 (Sinerem; Guerbet, France; and Combidex; Advanced Magnetics) at a dose of 2.6 mg Fe/kg using T2-weighted spin-echo and gradient-echo sequences. Surgery was performed the same day or the day after the ferumoxtran-10-enhanced MR examination. Based on MRI, selected nodes were surgically removed and directly correlated with pathology using hematoxylin-eosin (H&E) and Perls stainings. RESULTS: A total of 63 nodes were studied; 36 were nonmetastatic, 25 metastatic, and two inflammatory. Ferumoxtran-10-enhanced MRI allowed diagnosis of 24 metastatic and 30 nonmetastatic nodes, yielding a sensitivity of 96%, a specificity of 78.9%, a positive predictive value of 75%, and a negative predictive value of 96.8%, compared to 64%, 78.9%, 66.6%, and 76.9%, respectively, for nonenhanced MRI. Accuracy of ferumoxtran-10-enhanced MRI was 85.7%. The gradient-echo T2-weighted sequence was the most accurate to detect signal loss in nonmetastatic nodes. CONCLUSION: USPIO-enhanced MRI is useful for nodal staging of patients with head and neck cancers.     

位置偏差对格雷夫斯甲亢摄131I率测定及治疗剂量的影响

目的 评价摆位偏差对格雷夫斯甲状腺功能亢进(简称甲亢)甲状腺摄131I率(RAIU)、有效半减期(Teff)及131I治疗剂量的影响.方法 应用简单随机法选取20例格雷夫斯甲亢患者[男7例,女13例,平均年龄(46.60±9.55)岁],均于131I治疗前行RAIU测定:服用131I 74 kBq后分别测量2、4、6和24 h RAIU.标准测量方式(测量1):将甲状腺功能测定仪探头的标尺平行置于甲状软骨下缘,标尺距探头25 cm,每个时间点均测量2 min计数.在此基础上,分别将探头向后移动5 cm及上移5 cm再次测量,将其作为测量方式2(测量2)和3(测量3).经4h及24 h RAIU的3种摆位方式交叉组合得到9种不同组合(RAIU4h取测量1,RAIU24h分别取测量1、2、3时,组合方式分别记为CⅠ ～CⅢ;依次类推,RAIU4h取测量2、3时,组合方式有CⅣ～CⅨ)的RAIU、Teff和131I剂量,其中CⅠ为标准组.将CⅡ～CⅨ非标准组分别与CⅠ进行比较,采用配对t检验对结果进行统计学分析.结果 测量2和测量3获得的RAIU24h分别为(68.08±7.88)％、(62.18±7.45)％,均低于测量1(78.05±8.31)％(t=12.15和14.37,均P＜0.01);Teff:CⅡ为(4.42±0.73)d,CⅢ为(3.76±0.53)d,CV为(5.59±0.46)d,CⅥ为(4.47±0.44)d,CⅧ为(5.94±0.54)d和CⅨ为(5.45±0.66)d,与标准值(5.04±0.56)d比较,差异均有统计学意义(t:3.86～ 13.64,均P＜0.01).不正确的摆位导致的Teff变化及低RAIU使患者131I剂量计算值与标准值偏离,74.4％ (119/160)的剂量值明显高于标准组,而9.4％ (15/160)的值低于标准组.分析1例患者RAIU、Teff及131I剂量显示,与CⅠ相比,其RAIU24 h下降了26.0％,Teff的变化幅度达66.9％(-47.5％ ～ 19.4％).两种参数变化致131I计算剂量比标准值升高了129.8％.结论 RAIU测定中不正确摆位会导致RAIU测定的异常及Teff和131I剂量计算偏差,可能影响格雷夫斯甲亢患者的治疗结果.