Comparing performance of manual wheelchair skills using new and conventional rear anti-tip devices: randomized controlled trial

Kirby RL, Corkum CG, Smith C, Rushton P, MacLeod DA, Webber A. Comparing performance of manual wheelchair skills using new and conventional rear anti-tip devices: randomized controlled trial.

Objective

To test the hypotheses that, compared with participants using manual wheelchairs equipped with conventional rear anti-tip devices (C-RADs), those using a new RAD design that deploys through an arc (Arc-RAD) perform RAD-relevant wheelchair skills better and as safely.

Design

A randomized controlled study.

Setting

A rehabilitation center.

Participants

Participants (N=30) including 16 able-bodied and 14 wheelchair users.

Intervention

Participants were provided with wheelchair skills training (up to 2.4h).

Main Outcome Measures

Total percentage score on a set of 23 RAD-relevant skills of the Wheelchair Skills Test (WST, version 3.2) administered a minimum of 3 days after training.

Results

For the C-RAD and Arc-RAD groups, the mean ± standard deviation RAD-relevant WST scores were 32.3%±8.5% and 85.1%±18.9% (Kruskal-Wallis, P<.001). Of the 23 RAD-relevant individual skills, the success rates for the Arc-RAD group were at least 20% higher (the criterion we set for clinical significance) in 17 (74%). For the C-RAD group, the success rate was 0% for the 12 wheelie-dependent skills, the 13-cm-high obstacle, and the 15-cm level change ascent. There were no serious adverse effects in either group.

Conclusions

The new RAD design allows much better performance on relevant wheelchair skills than the conventional design without compromising safety.     

Effect of wheelchair tilt-in-space and recline angles on skin perfusion over the ischial tuberosity in people with spinal cord injury

Jan Y-K, Jones MA, Rabadi MH, Foreman RD, Thiessen A. Effect of wheelchair tilt-in-space and recline angles on skin perfusion over the ischial tuberosity in people with spinal cord injury.

Objective

To investigate the efficacy of wheelchair tilt-in-space and recline on enhancing skin perfusion over the ischial tuberosity in wheelchair users with spinal cord injury (SCI).

Design

Repeated-measures, intervention, and outcomes-measure design.

Setting

A university research laboratory.

Participants

Wheelchair users with SCI (N=11; 9 men, 2 women; mean ± SD age, 37.7±14.2y; body mass index, 24.7±2.6kg/m²; duration of injury, 8.1±7.5y).

Interventions

Protocols (N=6) of various wheelchair tilt-in-space and recline angles were randomly assigned to participants. Each protocol consisted of a 5-minute sitting-induced ischemic period and a 5-minute wheelchair tilt-in-space and recline pressure-relieving period. Participants sat in a position without tilt or recline for 5 minutes and then sat in 1 of 6 wheelchair tilted and reclined positions, including (1) 15° tilt-in-space and 100° recline, (2) 25° tilt-in-space and 100° recline, (3) 35° tilt-in-space and 100° recline, (4) 15° tilt-in-space and 120° recline, (5) 25° tilt-in-space and 120° recline, and (6) 35° tilt-in-space and 120° recline. A 5-minute washout period (at 35° tilt-in-space and 120° recline) was allowed between protocols.

Main Outcome Measures

Laser Doppler flowmetry was used to measure skin perfusion over the ischial tuberosity in response to changes in body positions caused by performing wheelchair tilt-in-space and recline. Skin perfusion response to wheelchair tilt-in-space and recline was normalized to skin perfusion of the upright seated position (no tilt/recline).

Results

Combined with 100° recline, wheelchair tilt-in-space at 35° resulted in a significant increase in skin perfusion compared with the upright seated position (no tilt/recline; P<.05), whereas there was no significant increase in skin perfusion at 15° and 25° tilt-in-space (not significant). Combined with 120° recline, wheelchair tilt-in-space at 15°, 25°, and 35° showed a significant increase in skin perfusion compared with the upright seated position (P<.05).

Conclusions

Our results indicate that wheelchair tilt-in-space should be at least 35° for enhancing skin perfusion over the ischial tuberosity when combined with recline at 100° and should be at least 25° when combined with recline at 120°. Although smaller angles of wheelchair tilt-in-space and recline are preferred by wheelchair users for functional purposes, wheelchair tilt-in-space less than 25° and recline less than 100° may not be sufficient for effective pressure reduction for enhancing skin perfusion over the ischial tuberosity in people with SCI.     

Comparison between a tilt-in-space wheelchair and a manual wheelchair equipped with a new rear anti-tip device from the perspective of the caregiver

Kirby RL, MacDonald B, Smith C, MacLeod DA, Webber A. Comparison between a tilt-in-space wheelchair and a manual wheelchair equipped with a new rear anti-tip device from the perspective of the caregiver.

Objective

To test the hypothesis that, in comparison with a commercially available tilt-in-space wheelchair, a lightweight manual wheelchair equipped with a new, rear anti-tip device (Arc-RAD) provides caregivers with improved wheelchair-handling performance, less exertion, and greater satisfaction.

Design

Within-participant comparisons.

Setting

Rehabilitation center.

Participants

Able-bodied participants (n=19) simulating caregivers and simulating wheelchair users (n=7).

Intervention

Caregiver participants were trained (50-75min) in wheelchair-handling skills.

Main Outcome Measures

Each participant was tested in both wheelchairs, in random order. To evaluate wheelchair-handling skills, we used the total percentage score on the Wheelchair Skills Test (WST), version 3.2. For exertion, we used a visual analog scale (in percent). For satisfaction, we used the Quebec Users' Evaluation of Satisfaction with assistive Technology (QUEST; range of values, 8-40), version 2.

Results

Mean percentage WST scores ± SD for the Arc-RAD and tilt-in-space wheelchairs were 95.9%±4.2%, and 91.9%±4.8%, respectively (P=.008). The mean perceived exertions during Arc-RAD and tilt-in-space wheelchair use were 26.1%±20.4% and 46.6%±23.2% (P=.003). The mean total QUEST satisfaction scores for the Arc-RAD and tilt-in-space wheelchairs were 35.1±3.8 and 28.4±4.7 (P=.002).

Conclusions

In comparison with the larger and heavier tilt-in-space wheelchair, a lightweight manual wheelchair equipped with a new rear anti-tip design allows 4.4% better wheelchair-handling performance, 44% less exertion, and 23.6% greater wheelchair satisfaction.     

Evaluation of pushrim-activated power-assisted wheelchairs using ANSI/RESNA standards

Karmarkar A, Cooper RA, Liu H, Connor S, Puhlman J. Evaluation of pushrim-activated power-assisted wheelchairs using ANSI/RESNA standards.

Objective

To determine and compare performance of pushrim-activated power-assisted wheelchairs (PAPAW) (iGLIDE, e-motion, Xtender) on national standards.

Design

Engineering performance and safety evaluation.

Setting

A Veteran Affairs and university-based research center.

Specimens

Nine PAPAWs.

Interventions

Not applicable.

Main Outcome Measures

Static, dynamic stability, brake effectiveness, maximum speed, acceleration, retardation, energy consumption, static, impact, and fatigue strength.

Results

There was no significant difference among the 3 models in forward stability. The iGLIDE was the most stable, whereas the e-motion was the least stable model in the rearward stability tests. All PAPAWs performed equally on the slopes of 3° and 6° in the forward and rearward directions. Braking distance was the highest for e-motion (5.64±0.28m) and the lowest (1.13±0.03m) for the iGLIDE in forward direction. The average equivalent cycles of all PAPAWs were 318,292±112,776.6 cycles (n=8) on the fatigue tests. All PAPAWs passed the impact and static strength tests.

Conclusions

The standards of the American National Standards Institute and the Rehabilitation Engineering and Assistive Technology Society of North America could act as quality assurance tool for wheelchairs. The standards for wheelchairs were first approved in 1990; after 17 years, exceeding the minimum values in the standards would be a reasonable expectation.     

Comparison of Trunk Proprioception Between Patients With Low Back Pain and Healthy Controls

Lee AS, Cholewicki J, Reeves NP, Zazulak BT, Mysliwiec LW. Comparison of trunk proprioception between patients with low back pain and healthy controls.

Objective

To determine whether proprioceptive impairments exist in patients with low back pain (LBP). We hypothesized that patients with LBP would exhibit larger trunk proprioception errors than healthy controls.

Design

Case-control study.

Setting

University laboratory.

Participants

24 patients with nonspecific LBP and 24 age-matched healthy controls.

Interventions

Not applicable.

Main Outcome Measures

We measured trunk proprioception in all 3 anatomical planes using motion perception threshold, active repositioning, and passive repositioning tests.

Results

LBP patients had significantly greater motion perception threshold than controls (P<.001) (1.3±0.9° vs 0.8±0.6°). Furthermore, all subjects had the largest motion perception threshold in the transverse plane (P<.001) (1.2±0.7° vs 1.0±0.8° for all other planes averaged). There was no significant difference between LBP and healthy control groups in the repositioning tasks. Errors in the active repositioning test were significantly smaller than in the passive repositioning test (P=.032) (1.9±1.2° vs 2.3±1.4°).

Conclusions

These findings suggest that impairments in proprioception may be detected in patients with LBP when assessed with a motion perception threshold measure.     

Association between mobility mode and C-reactive protein levels in men with chronic spinal cord injury

Morse LR, Stolzmann K, Nguyen HP, Jain NB, Zayac C, Gagnon D, Tun CG, Garshick E. Association between mobility mode and C-reactive protein levels in men with chronic spinal cord injury.

Objective

To assess clinical determinants of systemic inflammation in persons with chronic spinal cord injury (SCI).

Design

Cross-sectional survey.

Setting

Veterans Affairs medical center.

Participants

As part of an epidemiologic study assessing SCI-related health conditions, 63 men with chronic SCI provided a blood sample and information regarding locomotive mode and personal habits.

Interventions

Not applicable.

Main Outcome Measure

Plasma high-sensitivity C-reactive protein (CRP).

Results

The mean ± standard deviation age was 56±14y, and participants were assessed 21±13y after injury. Adjusting for heart disease, hypertension, and body mass index (BMI), the mean CRP in 12 motorized wheelchair users (5.11mg/L) was not significantly greater than 23 participants who used a manual wheelchair (2.19mg/L) (P=.085) but was significantly greater than the 17 who walked with an assistive device (1.41mg/L) (P=.005) and the 12 who walked independently (1.63mg/L) (P=.027). CRP was significantly greater in participants with obesity but was not related to age, smoking, or SCI level and severity. CRP was elevated in participants reporting a urinary tract infection (UTI) or pressure ulcer within a year, but adjustment for this did not account for the elevated CRP in motorized wheelchair users.

Conclusions

These results suggest that CRP in chronic SCI is independently related to locomotive mode, BMI, and a history of pressure ulcers and UTI. It is suggested that future studies in SCI investigate whether modifying these factors influence systemic inflammation and cardiovascular health.     

Development of a wheelchair virtual driving environment: trials with subjects with traumatic brain injury

Spaeth DM, Mahajan H, Karmarkar A, Collins D, Cooper RA, Boninger ML. Development of a wheelchair virtual driving environment: trials with subjects with traumatic brain injury.

Objective

To develop and test a wheelchair virtual driving environment that can provide quantifiable measures of driving ability, offer driver training, and measure the performance of alternative controls.

Design

A virtual driving environment was developed. The wheelchair icon is displayed in a 2-dimensional, bird's eye view and has realistic steering and inertial properties. Eight subjects were recruited to test the virtual driving environment. They were clinically evaluated for range of motion, muscle strength, and visual field function. Driving capacity was assessed by a brief trial with an actual wheelchair. During virtual trials, subjects were seated in a stationary wheelchair; a standard motion sensing joystick (MSJ) was compared with an experimental isometric joystick by using a repeated-measures design.

Setting

Subjects made 2 laboratory visits. The first visit included clinical evaluation, tuning the isometric joystick, familiarization with virtual driving environment, and 4 driving tasks. The second visit included 40 trials with each joystick.

Participants

Subjects (n=8; 7 men, 1 woman) with a mean age of 22.65±2y and traumatic brain injury, both ambulatory and nonambulatory, were recruited.

Interventions

The MSJ used factory settings. A tuning program customized the isometric joystick transfer functions during visit 1. During the second visit, subjects performed 40 trials with each joystick.

Main Outcome Measure

The root mean square error (RMSE) was defined as the average deviation from track centerline (in meters) and speed (in m/s).

Results

Data analysis from the first 8 subjects showed no statistically significant differences between joysticks. RMSE averaged .12 to .21m; speed averaged .75m/s. For all tasks and joysticks, driving in reverse resulted in a higher RMSE and more virtual collisions than forward driving. RMSE rates were greater in left and right turns than straight and docking tasks.

Conclusions

Testing with instrumented real wheelchairs can validate the virtual driving environment and assess whether virtual driving skills transfer to actual driving.     

Effect of botulinum toxin injection in the rectus femoris on stiff-knee gait in people with stroke: a prospective observational study

Stoquart GG, Detrembleur C, Palumbo S, Deltombe T, Lejeune TM. Effect of botulinum toxin injection in the rectus femoris on stiff-knee gait in people with stroke: a prospective observational study.

Objective

To study the effect of botulinum toxin type A (BTX-A) injection in the rectus femoris on the decreased knee flexion during the swing phase of gait (stiff-knee gait) in people with stroke.

Design

Intervention study (before-after trial) with an observational design.

Setting

Outpatient rehabilitation clinic and gait laboratory.

Participants

Nineteen chronic hemiparetic adults presenting with stiff-knee gait.

Intervention

Injection of 200U of BTX-A (Botox) into the rectus femoris.

Main Outcome Measures

Before and 2 months after BTX-A rectus femoris injection: Stroke Impairment Assessment Set (SIAS), Duncan-Ely test, and an instrumented gait analysis.

Results

Median SIAS score improved from 53 (range, 36−65) to 57 (range, 42−70) (signed-rank test, P=.005) and the Duncan-Ely score from 3 (range, 1−3) to 1 (range, 0−3) (P<.001). In gait analysis, mean (± standard deviation) maximum knee flexion improved from 26°±13° to 31°±14° during the swing phase (paired t test, P<.001), knee flexion speed at toe-off improved from 82°±63° to 112°±75°/s (P=.009), and knee negative joint power (eccentric muscular contraction) improved from −.27±.23 to −.37±.26W/kg (P<.001). The 4 patients who almost did not flex the knee (<10°) before the BTX-A rectus femoris injection did not improve after the injection. The other 14 patients who flexed the knee more than 10° before the BTX-A rectus femoris injection decreased the walking energy cost from 5.4±1.6 to 4.6±1.3J·kg⁻¹·m⁻¹ (P=.006).

Conclusions

BTX-A rectus femoris injection may be beneficial in patients with a stiff-knee gait after stroke, particularly in patients with some knee flexion (>10°).     

Prevalence of deep tissue injuries in hospitals and nursing homes: Two cross-sectional studies

Background

Deep tissue injuries are severe damages underneath the intact skin caused by long-endured, unrelieved pressure or shear forces. Empirical evidence regarding the magnitude of this health problem is limited.

Objective

Investigation of the prevalence, characteristics of persons affected and identification of the most affected body locations.

Design

Two cross-sectional studies in 2008 and 2009.

Settings

Nursing homes and hospitals throughout Germany.

Participants

6919 (year 2008) and 8451 (year 2009) hospital patients and nursing home residents.

Methods

Trained nurses conducted full skin assessments and collected demographic data based on written data collection forms. The Braden scale was used to measure pressure ulcer risk.

Results

Pressure ulcer prevalence including grades 1-4 and deep tissue injuries ranged from 4.3% (95% CI 3.8-4.9) in nursing homes to 7.1% (95% CI 6.2-8.0) in hospitals. Point prevalence rates of deep tissue injuries were 0.4% (95% CI 0.2-0.5) in hospitals and less than 0.1% in nursing homes. In total, 30 persons were affected by 38 deep tissue injuries. The mean age was 73.4 and the mean Braden scale sum score was 12.8. The most frequently affected anatomic sites were heels (n = 24) and ischial tuberosities (n = 6).

Conclusions

Nurses must be aware that deep tissue injuries exist in clinical practice. Deep tissue injuries seem to be more common in hospitals than in nursing homes and heels are more prone to this kind of injuries than other body sites. Whenever such a lesion is suspected, optimal pressure relief is required to enable the affected tissue to heal.     

Effects of ankle joint mobilizations in adults poststroke: a pilot study

Kluding PM, Santos M. Effects of ankle joint mobilizations in adults poststroke: a pilot study.

Objective

To compare the effect of 2 interventions on ankle mobility, ankle kinematics, and weight-bearing symmetry during functional activities in subjects with hemiparesis after a stroke.

Design

Randomized trial.

Setting

Academic medical center.

Participants

A convenience sample of 16 subjects with hemiparesis after stroke (mean age, 55.2y; mean time since stroke, 21.4mo).

Intervention

Subjects received 8 sessions over 4 weeks of either functional task practice combined with ankle joint mobilizations, or functional task practice only.

Main Outcome Measures

Changes in ankle range of motion (ROM) (not blinded), ankle kinematics during sit-to-stand (STS) and gait, and lower-extremity weight-bearing symmetry during STS and static standing.

Results

The combined intervention group gained 5.7°±3.1° in passive ankle ROM compared with 0.2°±2.6° in the functional practice only group (95% confidence interval [CI], 2.5-8.6; P<.01). No significant changes in ankle kinematics or weight bearing during static standing were noted in either group. The functional practice group decreased differences in weight bearing during STS by 9.5%±6.47%, whereas the combined intervention group increased this difference by 3.37%±5.29% (95% CI, 3.26-19.46; P=.01).

Conclusions

The increase in ankle motion did not improve joint kinematics and may have prevented improvement in weight-bearing symmetry.     

Relationship between resultant force at the pushrim and the net shoulder joint moments during manual wheelchair propulsion in elderly persons

Desroches G, Aissaoui R, Bourbonnais D. Relationship between resultant force at the pushrim and the net shoulder joint moments during manual wheelchair propulsion in elderly persons.

Objective

To determine the relationship between the resultant force at the pushrim and the net shoulder joint moments during manual wheelchair propulsion in elderly persons.

Design

Convenience sample.

Setting

Motion analysis laboratory.

Participants

Older manual wheelchair users (N=14; age, 68.2±5.2y) were tested.

Interventions

Kinematic and kinetic data were collected during manual wheelchair propulsion at a speed between 0.96 and 1.01m/s for 10 seconds and at a power output around 22.4W on a wheelchair ergometer.

Main Outcome Measures

Net shoulder joint moments were computed with an inverse dynamic model. The mechanical use of the forces at the pushrim and the mechanical fraction of effective force were measured during propulsion.

Results

Mechanical use and mechanical fraction of effective force had a positive and significant correlation with the net internal (P<.05) and external (P<.001) shoulder rotation moment, the net flexion (P<.05), and extension (P<.001) moment in the sagittal plane, and the net flexion (P<.001) moment in the horizontal plane.

Conclusions

The results suggest that because the resultant force at the pushrim has a greater tangential component and a greater proportion of the maximal voluntary force, most of the net moments around the shoulder are higher. Thus the optimal way of propelling, from a mechanical point of view (ie, tangential), may not be advantageous for manual wheelchair users.     

Design and Evaluation of a New Bladder Volume Monitor

Wang J, Hou C, Zheng X, Zhang W, Chen A, Xu Z. Design and evaluation of a new bladder volume monitor.

Objective

To introduce and evaluate a new implantable bladder volume monitor.

Design

Experimental study.

Setting

Animal laboratory.

Animals

Eight dogs.

Interventions

A coin-shaped permanent magnet was stitched onto the anterior bladder wall and a magnetic field sensor was fixed onto the lower abdominal external wall in 8 male dogs. The bladder was filled with sterile normal saline in consecutive steps of 25mL each from 0 to 200mL by a transurethral catheter.

Main Outcome Measure

Sensor readings were recorded after each step of bladder filling.

Results

The sensor baseline was set at 70° when the bladder was empty. After filling the bladders with 25, 50, 75, 100, 125, 150, 175, and 200mL saline water, the sensor readings were 74.6±0.9°, 79.6±1.2°, 84.5±0.9°, 90.1±0.8°, 95.5±1.1°, 101.8±2.1°, 110.5±2.9°, and 121.9±3.5°, respectively. Sensor readings were positively correlated with bladder volume (r=1; P<.01).

Conclusions

The design of a new bladder volume monitor that is made up of an external magnetic field sensor and an internal permanent magnet is reasonable and feasible. The new bladder volume monitor is simple in structure.     

Proprioception of the shoulder after stroke

Niessen MH, Veeger DH, Koppe PA, Konijnenbelt MH, van Dieën J, Janssen TW. Proprioception of the shoulder after stroke.

Objective

To investigate position sense and kinesthesia of the shoulders of stroke patients.

Design

Case-control study.

Setting

A rehabilitation center.

Participants

A total of 22 inpatients with stroke and 10 healthy control subjects.

Interventions

Not applicable.

Main Outcome Measures

Angular displacement (in degrees) for threshold to detection of passive motion (TDPM) tests and absolute error (in degrees) for passive reproduction of joint position tests.

Results

For patients, the TDPM for internal and external rotation was significantly higher for both the contralateral (paretic) side (internal, 7.92°±7.19°; external, 8.46°±8.87°) and the ipsilateral (nonparetic) side (internal, 4.86°±5.03°; external, 6.09°±9.15°) compared with the control group (internal, 1.83°±1.09°; external, 1.71°±.85°). Also, for internal rotation, TDPM was significantly higher for patients on the contralateral side compared with the ipsilateral side. For passive reproduction of joint position tests, no differences were found.

Conclusions

Both the contralateral and ipsilateral shoulders of stroke patients showed impaired TDPM. Passive reproduction of joint position does not seem to be affected as a result of a stroke. The control of the muscle spindles and central integration or processing problems of the afferent signals provided by muscle spindles might cause these effects.     

Implanted Electrical Stimulation of the Trunk for Seated Postural Stability and Function After Cervical Spinal Cord Injury: A Single Case Study

Triolo RJ, Boggs L, Miller ME, Nemunaitis G, Nagy J, Bailey SN. Implanted electrical stimulation of the trunk for seated postural stability and function after cervical spinal cord injury: a single case study.

Objectives

To explore and quantify the physical and functional effects of stabilizing the torso with electrical stimulation of the paralyzed hip and trunk musculature after motor complete tetraplegia.

Design

Single-subject case study with repeated measures and concurrent controls.

Setting

Academic outpatient rehabilitation center.

Participants

Forty-four-year-old man with C4 American Spinal Injury Association grade A tetraplegia 20 years postspinal cord injury.

Intervention

A surgically implanted multichannel pulse generator and intramuscular stimulating electrodes to activate lumbar erector spinae, quadratus lumborum, and gluteus maximus muscles bilaterally.

Main Outcome Measures

Outcomes assessed with and without stimulation included (1) spinal alignment and pelvic orientation, (2) pulmonary function and ventilatory volumes, (3) forward bimanual reaching distance, (4) seated stability and resistance to externally applied disturbances, (5) maximal force and speed of rowing-like movements, and the ability to (6) independently return to an erect seated position from full forward or lateral flexion and (7) roll in bed without assistance.

Results

Stimulation improved spinal convexity and kyphosis by 26° and 21°, reduced posterior pelvic tilt by 11°, increased forced expiratory volume and vital capacity by 10% and 22%, and improved forward reach by more than 7cm. Average resistance to sagittal disturbances increased by more than 40% (P<.002), and mean force exerted during underhanded pulling more than doubled (P=.014) with stimulation. Restoration of upright sitting in both sagittal and coronal planes and bed turning was made possible through appropriately timed activation of the hip and trunk muscles.

Conclusions

A neuroprosthesis for controlling the paralyzed torso can positively impact spinal alignment, seated posture, pulmonary function, trunk stability, and reach. Stimulation of hip and trunk muscles can improve performance of activities of daily living as well as enable independent wheelchair and bed mobility.     

Comparison of surface cooling and invasive cooling for rapid induction of mild therapeutic hypothermia in pigs--effectiveness of two different devices

Aim of the study

The effectiveness and safety of non-invasive surface cooling was compared to invasive endovascular cooling in an animal model.

Methods

Eight healthy pigs (29-38 kg) were cooled twice, starting in the first 4 pigs with unique surface cooling pads followed by endovascular cooling. In the second 4 pigs the order was reversed. The goal was to quickly lower pulmonary artery temperature from 38 to 33 °C. A paired t-test was used to compare cooling rates (°C/h, mean ± standard deviation) between both cooling techniques.

Results

Mean non-invasive surface cooling rate (11.9 ± 3.8 °C/h) significantly exceeded mean invasive cooling rate (3.9 ± 0.7 °C/h; p < 0.001). The mean difference in cooling rates was 8.0 ± 3.6 °C/h. No surface cooling related adverse skin reactions were observed.

Conclusions

Surface cooling is a simple method for achieving fast cooling rates. In our animal model, non-invasive cooling was three times faster than rapid endovascular cooling without overshoot.     

Head Posture and Neck Pain of Chronic Nontraumatic Origin: A Comparison Between Patients and Pain-Free Persons

Silva AG, Punt TD, Sharples P, Vilas-Boas JP, Johnson MI. Head posture and neck pain of chronic nontraumatic origin: a comparison between patients and pain-free persons.

Objective

To compare standing head posture measurements between patients with nontraumatic neck pain (NP) and pain-free individuals.

Design

Single-blind (assessor) cross-sectional study.

Setting

Hospital and general community.

Participants

Consecutive patients (n=40) with chronic nontraumatic NP and age- and sex-matched pain-free participants (n=40).

Interventions

Not applicable.

Main Outcome Measures

Three angular measurements: the angle between C7, the tragus of the ear, and the horizontal; the angle between the tragus of the ear, the eye, and the horizontal; and the angle between the inferior margins of the right and the left ear and the horizontal were calculated through the digitization of video images.

Results

NP patients were found to have a significantly smaller angle between C7, the tragus, and the horizontal, resulting in a more forward head posture than pain-free participants (NP, mean ± SD, 45.4°±6.8°; pain-free, mean ± SD, 48.6°±7.1°; P<.05; confidence interval [CI] for the difference between groups, 0.9°-6.3°). Dividing the population according to age into younger (≤50y) and older (>50y) revealed an interaction, with a statistically significant difference in head posture for younger participants with NP compared with younger pain-free participants (NP, mean ± SD, 46.1°±6.7°; pain-free, mean ± SD, 51.8°±5.9°; P<.01; CI for the difference between groups, 1.8°-9.7°) but no difference for the older group (NP, mean ± SD, 44.8°±7.1°; pain-free, mean ± SD, 45.1°±6.7°; P>.05; CI for the difference between groups, -4.9°-4.2°). No other differences were found between patients and pain-free participants.

Conclusions

Younger patients with chronic nontraumatic NP were shown to have a more forward head posture in standing than matched pain-free participants. However, the difference, although statistically significant, was perhaps too small to be clinically meaningful.     

Cardiovascular and metabolic responses during functional electric stimulation cycling at different cadences

Fornusek C, Davis GM. Cardiovascular and metabolic responses during functional electric stimulation cycling at different cadences.

Objective

To determine the influence of pedaling cadence on cardiorespiratory responses and muscle oxygenation during functional electric stimulation (FES) leg cycling.

Design

Repeated measures.

Setting

Laboratory.

Participants

Nine subjects with T4 through T10 spinal cord injury (SCI) (American Spinal Injury Association grade A).

Interventions

FES cycling was performed at pedaling cadences of 15, 30, and 50 revolutions per minute (rpm).

Main Outcome Measures

At each cadence, heart rate, oxygen uptake, and cardiac output were recorded during 35 minutes of cycling. Near infrared spectroscopy was used to quantify quadriceps muscle oxygenation.

Results

All pedaling cadences induced similar elevations in cardiorespiratory metabolism, compared with resting values. Higher average power output was produced at 30rpm (8.2±0.7W, P<.05) and 50rpm (7.9±0.5W, P<.05) compared with 15rpm (6.3±0.6W). Gross mechanical efficiency was significantly higher (P<.05) at 30 and 50rpm than at 15rpm. Quadriceps muscle oxygenation did not differ with pedaling cadences.

Conclusions

Cardiorespiratory responses and muscle metabolism adjustments during FES leg cycling were independent of pedal cadence. FES cycling at a cadence of 50rpm may not confer any advantages over 30 or 15rpm for cardiovascular fitness promotion in persons with SCI.     

Reliability of the performance and safety scores of the wheelchair skills test version 4.1 for manual wheelchair users

Lindquist NJ, Loudon PE, Magis TF, Rispin JE, Kirby RL, Manns PJ. Reliability of the performance and safety scores of the Wheelchair Skills Test Version 4.1 for manual wheelchair users.

Objective

To evaluate the interrater, intrarater, and test-retest reliability of the total performance and safety scores of the Wheelchair Skills Test version 4.1 (WST 4.1) for manual wheelchairs operated by adult wheelchair users.

Design

Cohort study.

Setting

University research setting.

Participants

People (N=11) who used manual wheelchairs for community locomotion.

Interventions

Not applicable.

Main Outcome Measure

Participants were videotaped as they completed the WST 4.1 (30 skills) on 2 separate occasions 1 to 2 weeks apart. Subsequently, raters scored the WST 4.1 from the video recordings and each participant received a total score for performance and safety. Using those scores, interrater, intrarater, and test-retest reliability were determined by using intraclass correlation coefficients (ICCs). Percentages of agreement between raters for individual skills also were calculated.

Results

Mean ± SD overall WST 4.1 scores for performance and safety were 80.1%±8.5% and 98.0%±2.8%. ICCs for the interrater, intrarater, and test-retest reliability of the performance component were .855, .950, and .901 (P<.001). Safety component ICC scores were .061 (P=.243), .228 (P=.048), and .254 (P=.041). Percentages of agreement between raters for each test item for both the performance and safety scales ranged from 68% to 100%.

Conclusions

Reliability of the performance component of the WST 4.1 was excellent, whereas ICCs for the safety component indicated only slight to fair agreement, probably because of the low variability in safety scores. Additional study is needed to further evaluate the reliability of the safety component with a larger and more diverse sample group.