Clinical Neurological Sciences Publications

Plantar Cutaneous Sensory Stimulation Improves Single-limb Support Time, and EMG Activation Patterns among Individuals with Parkinson's Disease

M. E. Jenkins et al. — Thu, 08 Mar 2012 20:03:24 PST

Parkinson's disease is a chronic neurological disorder that results in gait and posture impairment. There is increasing evidence that these motor impairments may be partially due to deficits within the sensory system. In this study, the effects of a facilitatory insole that provides increased plantar sensory stimulation, was evaluated during gait, in a group of individuals with Parkinson's disease in comparison with healthy age-matched controls. Spatial-temporal parameters of gait were evaluated using an instrumented carpet, and muscle activation patterns were evaluated using surface EMG. All participants were tested with both a facilitatory (ribbed) insole and a conventional (flat) insole while walking 20 feet. Results indicated that the use of the facilitatory insole produced a significant increase in single-limb support time. Additionally, the muscle activation sequence of the tibialis anterior was normalized by the facilitatory insole, at the time of initial ground contact. These changes may lead to an overall improvement in gait pattern and stability, and suggest that the use of this type of facilitatory insole may be a useful treatment strategy for improving the gait of individuals with Parkinson's disease. This also provides support for the role of facilitation of the sensory system in improving motor output in individuals with Parkinson's disease.

Predictive Validity of the UPDRS Postural Stability Score and the Functional Reach Test, When Compared with Ecologically Valid Reaching Tasks

M. E. Jenkins et al. — Tue, 06 Mar 2012 20:32:30 PST

Balance problems and falls are a common concern among individuals with Parkinson's disease (PD). Falls frequently occur during daily activities such as reaching into cupboards in the kitchen or bathroom. This study compared the correlation among two standard postural stability tests - the postural stability score on the Unified Parkinson's Disease Rating Scale (UPDRS) and the Functional Reach Test (FRT) - and ecologically valid reaching tasks that correspond to reaching at different cupboard heights among 20 individuals with PD and 20 age-matched controls. Both the FRT and the UPDRS postural stability tests are quick measures that can be performed during the clinical examination. The FRT, but not the postural stability score, demonstrated a significant correlation with the ecologically valid reaching tasks, among individuals with PD. Furthermore the FRT scores did not correlate with the UPDRS postural stability scores, indicating that these are measuring different aspects of balance. This study suggests that the FRT score may better predict the risk of postural instability encountered during daily activities among individuals with PD.

Creatine Monohydrate and Conjugated Linoleic Acid Improve Strength and Body Composition Following Resistance Exercise in Older Adults

Mark Tarnopolsky et al. — Mon, 05 Sep 2011 19:46:50 PDT

Aging is associated with lower muscle mass and an increase in body fat. We examined whether creatine monohydrate (CrM) and conjugated linoleic acid (CLA) could enhance strength gains and improve body composition (i.e., increase fat-free mass (FFM); decrease body fat) following resistance exercise training in older adults (>65 y). Men (N = 19) and women (N = 20) completed six months of resistance exercise training with CrM (5g/d)+CLA (6g/d) or placebo with randomized, double blind, allocation. Outcomes included: strength and muscular endurance, functional tasks, body composition (DEXA scan), blood tests (lipids, liver function, CK, glucose, systemic inflammation markers (IL-6, C-reactive protein)), urinary markers of compliance (creatine/creatinine), oxidative stress (8-OH-2dG, 8-isoP) and bone resorption (Nu-telopeptides). Exercise training improved all measurements of functional capacity (P<0.05) and strength (P<0.001), with greater improvement for the CrM+CLA group in most measurements of muscular endurance, isokinetic knee extension strength, FFM, and lower fat mass (P<0.05). Plasma creatinine (P<0.05), but not creatinine clearance, increased for CrM+CLA, with no changes in serum CK activity or liver function tests. Together, this data confirms that supervised resistance exercise training is safe and effective for increasing strength in older adults and that a combination of CrM and CLA can enhance some of the beneficial effects of training over a six-month period. Trial Registration. ClinicalTrials.gov NCT00473902.

High-risk Asymptomatic Carotid Stenosis: Ulceration on 3D Ultrasound vs TCD Microemboli

A. Madani et al. — Fri, 02 Sep 2011 16:12:21 PDT

OBJECTIVE: We compared microemboli on transcranial Doppler (TCD) with carotid ulcerations on 3D ultrasound (US) as an additional method for identifying the small proportion of patients with asymptomatic carotid stenosis (ACS) who can benefit from revascularization such as endarterectomy or stenting.

METHODS: Patients with ACS (n = 253) with carotid stenosis >60% by Doppler ultrasound were studied prospectively with TCD embolus detection and 3D US to detect ulcers (the total number of ulcers in both internal carotids) and followed for 3 years.

RESULTS: Mean age was 69.66 (SD 8.51) years; 11 (4%) had ≥3 ulcers (Ulcer 3), 11 (6%) had microemboli, and 25 (10%) had microemboli or ≥3 ulcers. Ulcer 3 patients were more likely to have a stroke or death in 3 years (18% vs 2%; p = 0.03), regardless of the side on which the ulcers were found. The 3-year risk of stroke or death was 20% with microemboli vs 2% without (p = 0.003). The annual rate of ipsilateral stroke was 0.8%.

CONCLUSION: Adding 3D US detection of ulcers doubles (to 10%) the proportion of patients with ACS who may benefit from endarterectomy or stenting. However, until 3-year event rates of stroke or death with endarterectomy or stenting reach <2%, 90% of patients with ACS would be better treated medically until they develop symptoms, ulcers, or emboli. Neurology® 2011;77:744-750.

Rules of Engagement: Residents' Perceptions of the In-training Evaluation Process

Christopher J. Watling et al. — Sun, 03 Apr 2011 18:38:00 PDT

BACKGROUND: In-training evaluation reports (ITERs) often fall short of their goals of promoting resident learning and development. Efforts to address this problem through faculty development and assessment-instrument modification have been disappointing. The authors explored residents' experiences and perceptions of the ITER process to gain insight into why the process succeeds or fails.

METHOD: Using a grounded theory approach, semistructured interviews were conducted with 20 residents. Constant comparative analysis for emergent themes was conducted.

RESULTS: All residents identified aspects of "engagement" in the ITER process as the dominant influence on the success of ITERs. Both external (evaluator-driven, such as evaluator credibility) and internal (resident-driven, such as self-assessment) influences on engagement were elaborated. When engagement was lacking, residents viewed the ITER process as inauthentic.

CONCLUSIONS: Engagement is a critical factor to consider when seeking to improve ITER use. Our articulation of external and internal influences on engagement provides a starting point for targeted interventions.

A Stronger Approach to Weakness in the Intensive Care Unit

G. Bryan Young et al. — Thu, 15 Oct 2009 15:20:10 PDT

ICU-acquired limb and respiratory muscle weakness is a common, serious ICU syndrome, increasing in frequency with prolonged ICU stay and sepsis. A systematic approach facilitates precise localization of the problem within central or peripheral nervous system. Most cases relate to critical illness polyneuropathy or myopathy or a combination of both (critical illness neuromyopathy). Within the latter entity, the relative contribution of neuropathy versus myopathy varies considerably among affected patients. Muscle enzyme testing, electromyography-nerve conduction and muscle biopsy are valuable investigative tests. Nerve biopsy is less commonly needed, but is useful when vascultis is suspected.