Shoulder pain in wheelchair users with tetraplegia and paraplegia

Transdermal nitroglycerine treatment of shoulder tendinopathies in patients with spinal cord injuries

STUDY DESIGN

A clinical blind study was conducted to determine the efficacy of transdermal nitroglycerine treatment on the awareness of shoulder pain.

OBJECTIVE

This study aims to determine the effects of transdermal nitroglycerine on shoulder pain and on functional shoulder movement in patients with spinal cord injuries and shoulder tendinopathies. A second aim is to establish the side effects of the treatment.

SETTING

Hospital "La Fe" in Valencia, Spain.

METHODS

A total of 45 spinal cord injury patients, all of whom are wheelchair users with shoulder tendinopathy, were randomly divided into two groups: placebo (n=12) and experimental (n=33). The experimental group (EG) received transdermal treatment for 6 months in the form of a 1.25 mg nitroglycerine (NT) patch on the greater tubercle. A placebo patch was used with the placebo subjects. Functional shoulder movements were assessed by articular range of motion and pain, using a visual analogical scale.

RESULTS

NT treatment reduced the awareness of shoulder pain and increased the functional movement and range of articular motion in the shoulders of the EG members (P<0.05).

CONCLUSIONS

We conclude that transdermal NT is an efficient method for treating shoulder tendinopathies in wheelchair users with spinal cord injuries.

Individual muscle contributions to push and recovery subtasks during wheelchair propulsion

Manual wheelchair propulsion places considerable physical demand on the upper extremity and is one of the primary activities associated with the high prevalence of upper extremity overuse injuries and pain among wheelchair users. As a result, recent effort has focused on determining how various propulsion techniques influence upper extremity demand during wheelchair propulsion. However, an important prerequisite for identifying the relationships between propulsion techniques and upper extremity demand is to understand how individual muscles contribute to the mechanical energetics of wheelchair propulsion. The purpose of this study was to use a forward dynamics simulation of wheelchair propulsion to quantify how individual muscles deliver, absorb and/or transfer mechanical power during propulsion. The analysis showed that muscles contribute to either push (i.e., deliver mechanical power to the handrim) or recovery (i.e., reposition the arm) subtasks, with the shoulder flexors being the primary contributors to the push and the shoulder extensors being the primary contributors to the recovery. In addition, significant activity from the shoulder muscles was required during the transition between push and recovery, which resulted in increased co-contraction and upper extremity demand. Thus, strengthening the shoulder flexors and promoting propulsion techniques that improve transition mechanics have much potential to reduce upper extremity demand and improve rehabilitation outcomes.

Strengthening and optimal movements for painful shoulders (STOMPS) in chronic spinal cord injury: a randomized controlled trial

BACKGROUND

Shoulder pain is a common problem after spinal cord injury (SCI), with negative effects on daily activities and quality of life (QOL).

OBJECTIVE

The purpose of this study was to determine the effect of an exercise program and instruction to optimize performance of upper-extremity tasks on shoulder pain in people with paraplegia from SCI.

METHODS

Design Eighty individuals with paraplegia from SCI and shoulder pain were randomly assigned to receive either an exercise/movement optimization intervention or an attention control intervention. The exercise/movement optimization intervention consisted of a 12-week home-based program of shoulder strengthening and stretching exercises, along with recommendations on how to optimize the movement technique of transfers, raises, and wheelchair propulsion. The attention control group viewed a 1-hour educational video. Outcome measures of shoulder pain, muscle strength (force-generating capacity), activity, and QOL were assessed at baseline, immediately after intervention, and 4 weeks later.

RESULTS

Shoulder pain, as measured with the Wheelchair User's Shoulder Pain Index, decreased to one third of baseline levels after the intervention in the exercise/movement optimization group, but remained unchanged in the attention control group. Shoulder torques, most 36-Item Short-Form Health Survey questionnaire (SF-36) subscale scores, and QOL scores also were improved in the exercise/movement optimization group, but not in the attention control group. Improvements were maintained at the 4-week follow-up assessment. Limitations Many of the outcome measures were self-reported, and the participant dropout rate was high in both groups. Additional studies are needed to determine whether the results of this study can be generalized to individuals with tetraplegia.

CONCLUSIONS

This home-based intervention was effective in reducing long-standing shoulder pain in people with SCI. The reduction in pain was associated with improvements in muscle strength and health-related and overall QOL.

Association of shoulder pain with the use of mobility devices in persons with chronic spinal cord injury

OBJECTIVE

To assess the prevalence of shoulder pain and its association with the use of assistive devices for mobility in persons with chronic spinal cord injury (SCI).

DESIGN

Cross-sectional analysis conducted within a cohort study.

SETTING

SCI service in a hospital and the community.

PARTICIPANTS

Between August 2005 and January 2008, 93 participants with chronic SCI completed a standardized health questionnaire and pain questionnaire.

MAIN OUTCOME MEASURES

Shoulder pain in last 6 months elicited by use of the McGill Pain Questionnaire pain diagram.

RESULTS

Of the 93 participants, 65 (69.9%) reported pain at any site in the 6 months before testing. Shoulder pain, reported by 39.8% of participants, was the third most common site of pain after the legs and back. When stratified by the use of assistive mobility devices, shoulder pain was reported by 46.7% of motorized wheelchair users, 35.4% of manual wheelchair users, 47.6% of participants using aids such as crutch(es) or canes, and 33.3% of participants walking without assistance (P = .7 for comparison of 4 groups).

CONCLUSIONS

Shoulder pain is highly prevalent in SCI. The authors of previous studies have largely attributed shoulder pain in SCI to manual wheelchair use. However, our results provide evidence for similarly elevated prevalence of shoulder pain among motorized wheelchair users and those patients using crutches or canes. This finding suggests that in addition to overuse injury from cyclic wheelchair propulsion, the assessment of other mechanical and nonmechanical factors that lead to shoulder pain in SCI is an unmet research need that may have treatment implications.

Elbow kinematics during overground manual wheelchair propulsion in individuals with tetraplegia

PURPOSE

The purpose of this study was to describe horizontal and vertical translation of the elbow and elbow angle in two planes and three speeds during manual wheelchair overground propulsion in individuals with tetraplegia.

METHODS

Seven individuals with tetraplegia who used manual wheelchairs wheeled overground at three different speeds were recruited for the study. Video motion capture methods quantified their movements. Video data were tracked and used to calculate variables describing three-dimensional elbow translation and angular orientation. Repeated measures ANOVA were used to determine effects of speed on elbow translation and elbow angle. Paired t-tests were used to evaluate left to right differences.

RESULTS

Right elbow anterior-posterior translation was found to be significantly different during slow and fast and slow and normal speeds. Vertical and medial-lateral translation of the right elbow was significantly different between slow and fast speeds. No significant effects for speed during left elbow movement or side-to-side movement were found. No significant effects were found for elbow angle across speeds or from side-to-side. Three patterns of elbow movement emerged for anterior-posterior and medial-lateral translation and for elbow angle.

CONCLUSIONS

Results indicated that elbow translation was related to propulsion speed. Work involving this population is needed for further understanding of upper extremity kinematic patterns.

Comparing the shoulder impingement kinematics between circular and pumping strokes in manual wheelchair propulsion

PURPOSE

The study aimed to investigate the glenohumeral kinematic difference between the circular and pumping strokes in manual wheelchair users.

METHOD

This is a repeated measures design with randomised testing conditions. We recruited 10 manual wheelchair users and asked them to perform both the pumping and circular strokes on a stationary roller system. We used the Zebris motion analysis system to collect the 3-dimension glenohumeral motion data.

RESULTS

The pumping and the circular strokes were similar in the starting and ending positions in the sagittal plane. However, the pumping stroke started at a significantly larger abduction and internal rotation and ended with a significantly larger abduction and even larger internal rotation, it also traveled more ranges in all three planes and stayed longer in the combined positions of rotation/flexion and rotation/abduction as compared to the circular stroke.

CONCLUSIONS

The circular stroke appeared more advantageous than the pumping technique in the injury prevention prospect because the latter involved more flexion, abduction and internal rotation of the shoulder, which could add more impingement stresses to the joint. Clinicians may need to prescribe proper wheelchair propulsion techniques for their clients to avoid accumulating impingement stresses in the shoulder joints.

Shoulder model validation and joint contact forces during wheelchair activities

Chronic shoulder impingement is a common problem for manual wheelchair users. The loading associated with performing manual wheelchair activities of daily living is substantial and often at a high frequency. Musculoskeletal modeling and optimization techniques can be used to estimate the joint contact forces occurring at the shoulder to assess the soft tissue loading during an activity and to possibly identify activities and strategies that place manual wheelchair users at risk for shoulder injuries. The purpose of this study was to validate an upper extremity musculoskeletal model and apply the model to wheelchair activities for analysis of the estimated joint contact forces. Upper extremity kinematics and handrim wheelchair kinetics were measured over three conditions: level propulsion, ramp propulsion, and a weight relief lift. The experimental data were used as input to a subject-specific musculoskeletal model utilizing optimization to predict joint contact forces of the shoulder during all conditions. The model was validated using a mean absolute error calculation. Model results confirmed that ramp propulsion and weight relief lifts place the shoulder under significantly higher joint contact loading than level propulsion. In addition, they exhibit large superior contact forces that could contribute to impingement. This study highlights the potential impingement risk associated with both the ramp and weight relief lift activities. Level propulsion was shown to have a low relative risk of causing injury, but with consideration of the frequency with which propulsion is performed, this observation is not conclusive.

Shoulder demands in manual wheelchair users across a spectrum of activities

OBJECTIVE

Investigate shoulder joint kinetics over a range of daily activity and mobility tasks associated with manual wheelchair propulsion to characterize demands placed on the shoulder during the daily activity of manual wheelchair users.

DESIGN

Case series.

SUBJECTS

Twelve individuals who were experienced manual wheelchair users.

METHODS

Upper extremity kinematics and handrim wheelchair kinetics were measured over level propulsion, ramp propulsion, start and stop over level terrain, and a weight relief maneuver. Shoulder intersegmental forces and moments were calculated from inverse dynamics for all conditions.

RESULTS

Weight relief resulted in significantly higher forces and ramp propulsion resulted in significantly higher moments than the other conditions. Surprisingly, the start condition resulted in large intersegmental moments about the shoulder equivalent with that of the ramp propulsion, while the demand imparted by the stop condition was shown to be equivalent to level propulsion across all forces and moments.

CONCLUSIONS

This study provides characterization of daily living and mobility activities associated with manual wheelchair propulsion not previously reported and identifies activities that result in higher shoulder kinetics when compared to standard level propulsion.

Evaluation of a wheelchair prototype with non-conventional, manual propulsion

OBJECTIVE

To evaluate the results of a user satisfaction questionnaire on a new type of lever-propelled wheelchair designed to avoid the discomfort and potential repetitive strain injuries related to conventional hand-rim propulsion.

METHODS

Seventeen participants filled out a questionnaire to rate their conventional wheelchair and the prototype (after 2 days' use) in terms of comfort, adjustability, steering/ride, manoeuvrability, stability when crossing obstacles, safety, weight, size, portability and appearance. Overall satisfaction was also scored.

RESULTS

According to the user questionnaire results, the lever-propelled prototype chair was rated as significantly superior than conventional wheelchairs in terms of comfort, safety and overall satisfaction. The prototype was rated significantly inferior in terms of size, adaptability, appearance and crossing obstacles.

CONCLUSION

We conclude that the prototype wheelchair is highly acceptable and comfortable and can be recommended to disabled sportspersons. The prototype's weak points are mainly related to ergonomic aspects, which could be improved in future models.

Effects of heavy resistance training on strength and power in upper extremities in wheelchair athletes

Little is known about strength training in subjects with spinal cord injury (SCI), especially in athletes performing competitive sports. Sixteen male subjects participated in this study-8 with SCI and 8 healthy physical education students (control subjects). The 8-week program consisted of heavy-resistance exercise performed twice per week with 10 to 12 repetitions in 5 sets. Subjects' performances were tested in static and in dynamic conditions concerning several strength and power parameters. Furthermore, we tested 10-m sprinting performance in wheelchair athletes. Overall, wheelchair athletes and control subjects achieved similar results; in almost all parameters both groups improved considerably in post-testing. Regarding percentages in most strength and power parameters, wheelchair athletes showed a tendency to benefit more from the strength training performed in the present study. Using analyses of group differences, however, only the comparison of effects on rate of force development (p = 0.010) resulted in a significant higher improvement for wheelchair athletes. In contrast to previous assumptions about minor adaptation capacities to training exercises in patients with SCI, our study proved clear effects of strength training. In conclusion, we suggest that heavy resistance training should be of increasing importance in wheelchair sports.

Prevalence of rotator cuff tear in paraplegic patients compared with controls

BACKGROUND

Musculoskeletal injuries of the shoulder in paraplegic patients with long-term survival can result from overuse and/or inappropriate use of wheelchairs. The purpose of the present study was to evaluate the prevalence and risk of pathological changes in the weight-bearing shoulder girdle of paraplegic patients who have been wheelchair-dependent for more than thirty years in comparison with able-bodied volunteers.

METHODS

One hundred paraplegic patients were matched for sex and age with a group of 100 able-bodied volunteers. Two hundred shoulders from each group were evaluated with use of magnetic resonance imaging. Collected outcome measures included a standardized clinical examination protocol, the Constant score, and a visual analog score for pain intensity.

RESULTS

Shoulder function according to the Constant score was significantly worse in the paraplegic patients than in the able-bodied volunteers. Similarly, the visual analog scale pain scores were significantly worse for the paraplegic patients. Magnetic resonance imaging showed that the prevalence of rotator cuff tears in either shoulder was significantly higher in the paraplegic patients than in the able-bodied volunteers (63% compared with 15%), resulting in a tenfold higher risk of rotator cuff rupture among paraplegic patients.

CONCLUSIONS

The present study demonstrates that the structural and functional changes of the shoulder joint are more severe and the risk of development of shoulder girdle damage is significantly higher in individuals with long-term paraplegia than in age-matched controls.

Sleep position and shoulder pain

The overuse theory for musculoskeletal joint pain cannot explain adequately the occurrence of shoulder pain in those who do not engage in activities that involve repeated and stressful use of the shoulder since the percentage of the painful right shoulders usually does not match the percentage of dominant right arms in such individuals. An alternative hypothesis is presented to propose that shoulder pain is caused by postural immobility in the decubitus or side position during sleep. Prolonged pressure on the shoulder caused by the weight of the thorax can produce enough damage to cause subsequent shoulder pain. In order to test this hypothesis, a preliminary study was carried out to compare the laterality of shoulder pain with the laterality of sleep position. The calculated laterality ratios for sleep position and shoulder pain were found to be strikingly similar, suggesting a causal relationship between the two phenomena. However, the prevalence of shoulder pain in the general population was found to be smaller than the percentage of the time people would spend sleeping in the decubitus position. This discrepancy could be explained by the idea that in order for shoulder pain to develop subjects may have to spend longer times in the same decubitus position before changing to another position than the average person would. Additional evidence from published clinical studies also supports the postural theory of shoulder pain. More studies can be done to test this hypothesis by focusing on the sleep habits of patients with shoulder pain. According to the present hypothesis shoulder pain should for the most part occur on the side that the patient preferred to sleep on before the onset of shoulder pain. The postural theory of shoulder pain provides the possibility for a new and noninvasive method to treat shoulder pain by the modification of posture during sleep.

Pain after paraplegia: a survey in India

STUDY DESIGN

A postal survey.

OBJECTIVE

To ascertain the incidence of pain in individuals with paraplegia in India and to associate it with demographic characteristics.

SETTING

India.

METHOD

The study was done by means of a questionnaire. This questionnaire was mailed to the identified individuals (n=600) on the addresses obtained from the medical records section of hospitals and from various organizations. Data analysis was done by using non-parametric tests of association.

RESULTS

The return rate was 46% (276/600). Fifty-seven percent of individuals complained of pain. Of this, pain in the back and chest ranked the highest (30.1%), followed by pain below the level of lesion (6.9%), pain in the shoulder and upper limb (4.7%) and neck (0.4%). Fifteen percent of individuals complained of pain at multiple sites. We found a significant association of pain with age, duration since injury and ambulation.

CONCLUSION

More than half of the subjects complained of pain in the study. Pain was found to be associated with age, duration since injury and ambulation. As pain has a dramatic effect on a subjects' quality of life, there is a need to evaluate it in detail and treat accordingly with preventive, rehabilitative or surgical procedures.

Effects of hand cycle training on physical capacity in individuals with tetraplegia: a clinical trial

BACKGROUND

Regular physical activity is important for people with tetraplegia to maintain fitness but may not always be easily integrated into daily life. In many countries, hand cycling has become a serious option for daily mobility in people with tetraplegia. However, little information exists regarding the suitability of this exercise mode for this population.

OBJECTIVE

The purpose of this study was to evaluate the effects of a structured hand cycle training program in individuals with chronic tetraplegia.

DESIGN

Pretraining and posttraining outcome measurements of physical capacity were compared.

SETTING

Structured hand cycle interval training was conducted at home or in a rehabilitation center in the Netherlands.

PARTICIPANTS

Twenty-two patients with tetraplegia (American Spinal Injury Association Impairment Scale classification A-D) at least 2 years since injury participated.

INTERVENTION

The intervention was an 8- to 12-week hand cycle interval training program.

MEASURES

Primary outcomes of physical capacity were: peak power output (POpeak) and peak oxygen uptake (Vo(2)peak), as determined in hand cycle peak exercise tests on a motor-driven treadmill. Secondary outcome measures were: peak muscle strength (force-generating capacity) of the upper extremities (as assessed by handheld dynamometry), respiratory function (forced vital capacity and peak expiratory flow) and participant-reported shoulder pain.

RESULTS

Significant improvements following a mean of 19 (SD=3) sessions of hand cycle training were found in POpeak (from 42.5 W [SD=21.9] to 50.8 W [SD=25.4]), Vo(2)peak (from 1.32 L.min(-1) [SD=0.40] to 1.43 L.min(-1) [SD=0.43]), and mechanical efficiency, as reflected by a decrease in submaximal oxygen uptake. Except for shoulder abduction strength, no significant effects were found on the secondary outcomes.

LIMITATIONS

Common health complications, such as urinary tract infections, bowel problems, and pressure sores, led to dropout and nonadherence.

CONCLUSION

Patients with tetraplegia were able to improve their physical capacity through regular hand cycle interval training, without participant-reported shoulder-arm pain or discomfort.

Impact of Gender on Shoulder Torque and Manual Wheelchair Usage for Individuals with Paraplegia: A Preliminary Report

BACKGROUND: The prevalence of women with spinal cord injury is increasing, and their unique attributes merit attention, specifically, shoulder strength and community wheelchair propulsion. RESULTS: Shoulder torques were 62%-96% greater in men than women, average daily distance traveled was greater for men, and average speeds were similar. CONCLUSIONS: Community wheelchair propulsion speed was similar between men and women but men were significantly stronger, therefore daily mobility requires a higher relative effort for women's shoulder muscles. This demand may increase susceptibility to fatigue and development of shoulder pain.

Effects of resistance and endurance training in persons with paraplegia

INTRODUCTION

The specific effects of resistance and endurance training on upper extremity work capacity, muscular strength, and anaerobic power in chronic survivors of paraplegia have not been previously determined.

PURPOSE

This study compared the effects of 12 wk of endurance training (ET) with 12 wk of resistance training (RT) on VO(2peak), upper extremity strength, and power output in persons with chronic paraplegia.

METHODS

Eighteen subjects with neurologically complete paraplegia, T6-T10, participated in three weekly exercise sessions during a 12-wk training period. Subjects were matched into pairs (body mass and gender) and were randomly assigned to ET or RT. The ET group performed 30 min of arm cranking at 70%-85% of HR(peak). The RT group performed three sets of 10 repetitions at six exercise stations with an intensity of ranging from 60% to 70% of 1 repetition maximum (1RM). Values of upper extremity strength (1RM) were established using the Mayhew regression equation. VO(2peak) was determined during arm ergometry testing using open circuit spirometry. Arm Wingate anaerobic testing (WAnT) was used to determine subjects' peak and mean anaerobic power output.

RESULTS

VO(2peak) values were significantly greater after RT (15.1%) and ET (11.8%). Muscular strength significantly increased for all exercise maneuvers in the RT group (P values < 0.01) with no changes detected in the ET group. Mean WAnT power increased in the RT and ET groups by 8% and 5%, respectively. The RT group displayed significantly greater gains in peak WAnT power (P < 0.001) than ET, 15.6% and 2.6%, respectively.

CONCLUSION

Persons with paraplegia can significantly improve their upper extremity work capacity, muscular strength, and power by participating in RT.

Comparison between performance with a pushrim-activated power-assisted wheelchair and a manual wheelchair on the Wheelchair Skills Test

PURPOSE

To test the hypothesis that people using a pushrim-activated power-assisted wheelchair (PAPAW) can accomplish a wider range of wheelchair skills than when using a manual wheelchair (MWC).

METHODS

We studied 30 able-bodied participants, using within-participant comparisons. Participants used a manual wheelchair equipped with both PAPAW and regular MWC rear wheels, and rear anti-tip devices (Arc-RADs) that permitted wheelie-like function. We trained participants to perform the wheelchair skills of the Wheelchair Skills Training Program (WSTP, Version 2.4). From the Wheelchair Skills Test (WST, Version 2.4), we calculated pass-fail success rates for the 50 individual skills and a total percentage WST score.

RESULTS

The mean (+/-SD) total WST scores were 89.3 (+/-7.0)% for the PAPAW and 88.8 (+/-8.4)% for the MWC, with a mean difference of 0.6 (+/-5.6)% (p = 0.59). Qualitative observations suggested that skills requiring a higher force on the pushrim (e.g., incline ascent) were performed more easily with the PAPAW, whereas skills requiring greater control of the wheelchair (e.g., wheelie-dependent skills) were performed more easily with the MWC.

CONCLUSION

Overall wheelchair skill performance with the PAPAW is not superior to that when using the MWC. The PAPAW may be helpful for specific skills that require more wheel torque, but the additional torque appears to be disadvantageous when performing skills that require greater control.

Comparison of kinematics, kinetics, and EMG throughout wheelchair propulsion in able-bodied and persons with paraplegia: an integrative approach

A systematic integrated data collection and analysis of kinematic, kinetic, and electromyography (EMG) data allow for the comparison of differences in wheelchair propulsion between able-bodied individuals and persons with paraplegia. Kinematic data from a motion analysis system, kinetic data from force-sensing push rims, and electromyography data from four upper-limb muscles were collected for ten push strokes. Results are as follows: Individuals with paraplegia use a greater percentage of their posterior deltoids, biceps, and triceps in relation to maximal voluntary contraction. These persons also reached peak anterior deltoid firing nearly 10 deg earlier on the push rim, while reaching peak posterior deltoid nearly 10 deg later on the push rim. Able-bodied individuals had no triceps activity in the initial stages of propulsion while their paraplegic groups had activity throughout. Able-bodied participants also had, on average, peak resultant, tangential, and radial forces occurring later on the push rim (in degrees). There are two main conclusions that can be drawn from this integrative investigation: (1) A greater "muscle energy," as measured by the area under the curve of the percentage of EMG throughout propulsion, results in a greater resultant joint force in the shoulder and elbow, thus potentially resulting in shoulder pathology. (2) Similarly, a greater muscle energy may result in fatigue and play a factor in the development of shoulder pain and pathology over time; fatigue may compromise an effective propulsive stroke placing undue stresses on the joint capsule. Muscle activity differences may be responsible for the observed kinematic and kinetic differences between the two groups. The high incidence of shoulder pain in manual wheelchair users as compared to the general population may be the result of such differences, although the results from this biomedical investigation should be examined with caution. Future research into joint forces may shed light on this. Further investigation needs to focus on whether the pattern of kinematics, kinetics, and muscle activity during wheelchair propulsion is compensatory or evolutionary by tracking individuals longitudinally.

Research priorities: wheeled mobility

PURPOSE

To bring together an interdisciplinary group of leaders in the field of seating and wheeled mobility to discuss and exchange information about the methodological challenges of studying health, activity and participation of wheelchair users. This article summarizes the discussions from the Wheeled Mobility breakout groups.

METHODS

Conference attendees were provided with wheeled mobility priority topics determined by consensus. Groups were tasked with configuring a research topic into a research project. Each group was provided with a general framework to guide discussions: identify research questions, specific aims or hypotheses, study design possibilities, recruitment considerations, measurement variables and tools, analysis considerations and anticipated methodological challenges.

RESULTS

The four priority research topics examined were: Impact of mobility equipment on health outcomes; Relating activity and participation to health outcomes; Impact of wheelchair design on function; and Health impacts of long-term wheelchair use.

CONCLUSIONS

Synopses were compiled from group notes and presented to all conference attendees. Groups identified several challenges that require consideration, a few examples include: recruitment of homogeneous samples, controlling for biases, sample sizes, complexities of multisite studies, intrusive monitoring and measures, validity and reliability of test environment.

The influence of verbal training and visual feedback on manual wheelchair propulsion

PURPOSE

To determine if verbal training with visual feedback improved manual wheelchair propulsion; to examine propulsion differences between an individual with paraplegia and an individual with tetraplegia.

METHOD

Quasi-experimental study: Nine manual wheelchair-using adults participated in propulsion assessments and training. Baseline propulsion performance was measured on several tasks on different surfaces. Participants were trained on a wheelchair treadmill with verbal and visual feedback to increase push length, reduce push frequency and to modify propulsion pattern. Handrim biomechanics were measured with an instrumented wheel. Changes in propulsion were assessed. Differences in propulsion characteristics between a participant with paraplegia and a participant with tetraplegia were examined.

RESULTS

Push length increased (p < 0.05), push frequency decreased (p < 0.01) and peak (p < 0.05) and average (p < 0.01) forces increased immediately after training. These changes were not sustained over time. Graphic representations showed differences in propulsion characteristics between a participant with paraplegia and a participant with tetraplegia.

CONCLUSIONS

Verbal training may produce changes in push biomechanics of manual wheelchair users. Longer training periods may be needed to sustain propulsion changes. Findings from this study support other studies that have shown propulsion differences between people with tetraplegia and paraplegia. Propulsion training for populations with upper-extremity impairments warrants further study.

Redefining the manual wheelchair stroke cycle: identification and impact of nonpropulsive pushrim contact

OBJECTIVES

To create a comprehensive definition of the manual wheelchair stroke cycle, which includes multiple periods of pushrim contact, and to show its improved clinical benefit to wheelchair propulsion analyses.

DESIGN

Cross-sectional biomechanics study.

SETTING

Three motion analysis laboratories.

PARTICIPANTS

Persons (N=54) with paraplegia who use a manual wheelchair.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Pushrim forces, axle moments, and contact angles measured during wheelchair propulsion.

RESULTS

Total force on the pushrim was used to define pushrim contact and positive axle moment was used to identify the included period of propulsive contact. During most strokes, periods of nonpropulsive contact existed before and after propulsive contact. Within these periods, braking moments were applied to the pushrim, resulting in negative power output, or power loss. Including nonpropulsive data decreased mean stroke moment and power. The magnitude and the angle over which braking moments and power loss occurred increased with wheel speed. Mean braking moment and power loss within the initial contact period were significantly (P<.001) related to stroke pattern.

CONCLUSIONS

The proposed definition of the stroke cycle provides a thorough and practical description of wheelchair propulsion. Researchers and clinicians should use this definition to understand and minimize the impact of nonpropulsive contact throughout the stroke.

Shoulder ultrasound abnormalities, physical examination findings, and pain in manual wheelchair users with spinal cord injury

OBJECTIVES

To investigate the presence of ultrasound (US) abnormalities in manual wheelchair users with spinal cord injury (SCI) using a quantitative Ultrasound Shoulder Pathology Rating Scale (USPRS). To investigate physical examination (PE) findings using a quantitative Physical Examination of the Shoulder Scale (PESS), and to obtain data about pain and other subject characteristics such as age, years with SCI, and weight.

DESIGN

Case series.

SETTING

National Veterans' Wheelchair Games 2005 and 2006.

PARTICIPANTS

Volunteer sample of manual wheelchair users with SCI participating in the National Veterans' Wheelchair Games.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Presence of relationships between US findings, PE findings, pain, and subject characteristics.

RESULTS

The USPRS correlated with age, duration of SCI, and weight (all P<.01), and showed a positive trend with the total Wheelchair User's Shoulder Pain Index (WUSPI) score (r=.258, P=.073). Several US findings related to presence of PE findings for specific structures. The PESS score correlated with the WUSPI (r=.679, P<.001) and duration of SCI (P<.05). The presence of untreated shoulder pain that curtailed activity was noted in 24.5% of subjects, and this was related to increased WUSPI scores (P=.002).

CONCLUSIONS

PE and US abnormalities are common in manual wheelchair users with SCI. The USPRS and PESS demonstrated evidence for external validity and hold promise as research tools. Untreated shoulder pain is common in manual wheelchair users with SCI, and further investigation of this pain is indicated.

Biomechanic evaluation of upper-extremity symmetry during manual wheelchair propulsion over varied terrain

OBJECTIVE

To evaluate upper-extremity symmetry during wheelchair propulsion across multiple terrain surfaces.

DESIGN

Case series.

SETTING

A biomechanics laboratory and the general community.

PARTICIPANTS

Manual wheelchair users (N=12).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Symmetry indexes for the propulsion moment, total force, tangential force, fractional effective force, time-to-peak propulsion moment, work, length of push cycle, and power during wheelchair propulsion over outdoor and indoor community conditions, and in laboratory conditions.

RESULTS

Upper-extremity asymmetry was present within each condition. There were no differences in the magnitude of asymmetry when comparing laboratory with indoor community conditions. Outdoor community wheelchair propulsion asymmetry was significantly greater than asymmetry measured during laboratory conditions.

CONCLUSIONS

Investigators should be aware that manual wheelchair propulsion is an asymmetrical act, which may influence interpretation when data is collected from a single limb or averaged for both limbs. The greater asymmetry identified during outdoor versus laboratory conditions emphasizes the need to evaluate wheelchair biomechanics in the user's natural environment.

Wheelchair propulsion demands during outdoor community ambulation

OBJECTIVE

Quantify manual wheelchair propulsion effort during outdoor community ambulation.

DESIGN

Case series.

SUBJECTS

Thirteen individuals (12 with SCI, 1 with spina bifida) who were experienced manual wheelchair users and had no current upper extremity injury or pain complaints.

METHODS

Measurements were obtained from instrumented wheelchair rims during steady-state propulsion as subjects traversed outdoor concrete sidewalk terrain that included smooth level, aggregate level, and a ramp with a smooth surface. Propulsion effort was assessed using the average propulsion moment, average instantaneous power, and work for both upper extremities.

RESULTS

Propulsion effort, captured by the propulsion moment, work and power, varied across ground conditions (p<0.001). Propulsion effort was greater as the rolling resistance increased (i.e., smooth versus aggregate surfaces) and as the inclination angle progressed from level to inclined surfaces. There were no side-to-side differences across ground conditions for the propulsion moment or work. Power generation was significantly greater on the dominant compared to the non-dominant extremity during the more challenging aggregate surface and ramp conditions.

CONCLUSIONS

Propulsion effort varies with demands imposed by different ground conditions. Quantification of wheelchair propulsion demands provides rehabilitations specialists with objective information to guide treatment of patients adapting to manual wheelchair use.

Mechanical efficiency and propulsion technique after 7 weeks of low-intensity wheelchair training

BACKGROUND

To evaluate the effect of a 7-week low-intensity hand rim wheelchair training on the submaximal metabolic cost, mechanical efficiency and propulsion technique in able-bodied participants.

METHODS

Participants were randomly divided over an experimental group (n=14) and a control group (n=7). The experimental group received 7 weeks wheelchair training (3 week(-1), 70 min) at a low intensity (30% of the heart rate reserve), whereas the control group did not receive training. During pre- and post-tests, submaximal exercise was performed on a stationary wheelchair ergometer at fixed levels of power output. Mechanical efficiency, oxygen uptake, heart rate, timing parameters and stroke angles were measured. Video recordings were made to determine the stroke pattern.

FINDINGS

Mechanical efficiency increased and metabolic cost decreased significantly in the experimental group compared to the control group. Push time increased and cycle frequency decreased as a result of training. The stroke angle increased in the experimental group during the training period. The experimental group preferred double-looping over propulsion, while the control group mainly used single-looping over propulsion patterns during the post-test.

INTERPRETATION

A low-intensity, 7-week training protocol has a beneficial effect on the mechanical efficiency and metabolic cost of wheelchair propulsion in able-bodied participants. The improved mechanical efficiency seems to be the result of changes in propulsion technique that were found.

Pain intensity, pain interference and characteristics of spinal cord injury

STUDY DESIGN

Postal survey.

OBJECTIVES

To examine if the intensity of pain in persons with spinal cord injury (SCI) varied as a function of pain site, and to identify the patient and SCI characteristics associated with pain location, pain intensity and pain interference in a sample of persons with SCI.

SETTING

Community sample, United States.

METHODS

A postal survey including measures of pain intensity, pain interference, other pain, demographic and medical characteristics was completed by 238 adults with SCI.

RESULTS

Average pain intensity was moderate and pain was common across the body. Demographic and medical variables, including SCI level, were generally not associated with pain prevalence, intensity and interference. However, persons with higher level injuries were more likely to report upper extremity pain than persons with paraplegic injuries. The lower body was the location of the highest pain ratings.

CONCLUSION

Persons with SCI tend to experience high pain intensity over multiple body locations. Lower body pain was as common as upper extremity pain, but tended to be more intense.

The natural-fit handrim: factors related to improvement in symptoms and function in wheelchair users

BACKGROUND/OBJECTIVE

People with spinal cord injury (SCI) may spend several decades using a wheelchair as their primary means of mobility. Secondary injury and a decline in independence over time are common with manual wheelchair users who, in turn, may require increased assistance as time passes. The Natural-Fit contoured handrim has been shown to improve symptoms and function in people with SCI who use manual wheelchairs and who have experienced upper extremity pain. The objective of this study was to determine the factors associated with improved symptoms and functions.

PARTICIPANTS

87 people who purchased the ergonomic wheelchair handrims. Participants were predominately men, with a median age of 51 to 55 years, median level of injury T10 to T12, median time in a wheelchair of 15 years, and they had used the contoured rims for 1 to 2 years.

METHODS

This was a mail survey of 217 people who purchased the rims. The survey was mailed out from the manufacturer and was anonymously returned to the physical therapy department of a university. A $10 incentive was offered for returning the survey.

RESULTS

The majority of participants reported improvements in upper extremity symptoms, ease of wheelchair propulsion, and functional status. Longer use of the rims was associated with reported improvement in ease of wheelchair propulsion and reduction in pain in hands and wrists.

CONCLUSION

If a simple modification of the wheelchair can help bring about significant changes in the users' symptoms and function, this modification should be incorporated by people who use manual wheelchairs before decline in function begins. Proactive intervention may alleviate symptoms, help the person maintain maximal independence, and prolong the length of time the individual remains independent.

Factors affecting shoulder pain in adolescents and young adults with spina bifida

PURPOSE

This study was designed to determine whether factors affecting shoulder pain in adults with spinal cord injury also affected adolescent and young adult manual wheelchair users with spina bifida.

METHODS

Forty-one participants with spina bifida rated their pain using the Wheelchair User's Shoulder Pain Index.

RESULTS

Results showed no significant relationship between shoulder pain and age or duration of wheelchair use but significant differences in pain between age groups. Participation in a sports program and level of lesion were not factors in pain intensity. Propelling up an incline was the activity for which the highest intensity of pain was reported.

CONCLUSION

Shoulder pain in adolescents and young adults with spina bifida is not as great as previously reported in adults with spinal cord injuries but older subjects had greater pain than younger subjects.

Comparative shoulder kinematics during free standing, standing depression lifts and daily functional activities in persons with paraplegia: considerations for shoulder health

STUDY DESIGN

Case series; nonparametric repeated-measures analysis of variance.

OBJECTIVE

To compare and contrast three-dimensional shoulder kinematics during frequently utilized upper extremity weight-bearing activities (standing depression lifts used in brace walking, weight-relief raises, transfers) and postures (sitting rest, standing in a frame) in spinal cord injury (SCI).

SETTING

Movement Analysis Laboratory, Department of Physical Therapy, Ithaca College, Rochester, NY, USA.

METHODS

Three female and two male subjects (39.2+/-6.1 years old) at least 12 months post-SCI (14.6+/-6.7 years old), SCI distal to T2 and with an ASIA score of A. The Flock of Birds magnetic tracking device was used to measure three-dimensional positions of the scapula, humerus and thorax during various activities.

RESULTS

Standing in a frame resulted in significantly less scapular anterior tilt (AT) and greater glenohumeral external rotation (GHER) than standing depression lifts and weight-relief raises.

CONCLUSIONS

Standing frame posture offers the most favorable shoulder joint positions (less scapular AT and greater GHER) when compared to sitting rest posture, weight-relief raises, transfers and standing depression lifts. Knowledge of kinematic patterns associated with each activity is an essential first step to understanding the potential impact on shoulder health. Choosing specific activities or modifying techniques within functional activities that promote favorable shoulder positions may preserve long-term shoulder health.

Acupuncture for Chronic Shoulder Pain in Persons With Spinal Cord Injury: A Small-Scale Clinical Trial

OBJECTIVE

To determine the efficacy of acupuncture in the treatment of chronic musculoskeletal shoulder pain in subjects with spinal cord injury (SCI).

DESIGN

Randomized, double blind (participants, evaluator), placebo (invasive sham) controlled trial.

SETTING

Clinical research center.

PARTICIPANTS

Seventeen manual wheelchair-using subjects with chronic SCI and chronic musculoskeletal shoulder pain.

INTERVENTIONS

Participants were randomly assigned to receive 10 treatments of either acupuncture or invasive sham acupuncture (light needling of nonacupuncture points).

MAIN OUTCOME MEASURE

Changes in shoulder pain intensity were measured using the Wheelchair User's Shoulder Pain Index.

RESULTS

Shoulder pain decreased significantly over time in both the acupuncture and the sham acupuncture groups (P=.005), with decreases of 66% and 43%, respectively. There was no significant difference between the 2 groups (P=.364). There was, however, a medium effect size associated with the acupuncture treatment.

CONCLUSIONS

There appears to be an analgesic effect or a powerful placebo effect associated with both acupuncture and sham acupuncture. There was a medium treatment effect associated with the acupuncture, which suggests that it may be superior to sham acupuncture. This observation, along with the limited power, indicates that a larger, more definitive randomized controlled trial using a similar design is warranted.

Obesity after spinal cord injury

America is in the midst of an obesity epidemic, and individuals who have spinal cord injury (SCI) are perhaps at greater risk than any other segment of the population. Recent changes in the way obesity has been defined have lulled SCI practitioners into a false sense of security about the health of their patients regarding the dangers of obesity and its sequelae. This article defines and uses a definition of obesity that is more relevant to persons who have SCI, reviews the physiology of adipose tissue, and discusses aspects of heredity and environment that contribute to obesity in SCI. The pathophysiology of obesity is discussed relative to health risks for persons who have SCI, particularly those contributing to cardiovascular disease. Prevalence of obesity and its comorbidities are discussed and management options reviewed.

Ultrasonographic findings in shoulders of able-bodied, paraplegic and tetraplegic subjects

STUDY DESIGN

Cross-sectional.

OBJECTIVES

To evaluate the association between spinal cord injury (SCI) and ultrasonographic findings in shoulders.

SETTING

Randomly selected patients of Käpylä Rehabilitation Centre and able-bodied citizens of Helsinki, Finland.

METHODS

Ultrasonography of the shoulder was performed on able-bodied, tetraplegic and paraplegic subjects. Subjects with SCI were selected from patients of Käpylä Rehabilitation Centre, who were injured more than 3 months before the examination.

RESULTS

Findings of the glenohumeral joint differed most clearly between the groups. Significant association between SCI level and oedema of the glenohumeral joint was noted in multiple regression analysis, where other background factors were also considered.

CONCLUSION

Paraplegic and tetraplegic subjects are prone to glenohumeral changes that can be verified with ultrasonography.

Ultrasound Imaging of Acute Biceps Tendon Changes After Wheelchair Sports

OBJECTIVES

To investigate acute changes in the biceps tendon after a high-intensity wheelchair propulsion activity and to determine whether these changes are related to subject characteristics.

DESIGN

The biceps tendon was imaged with ultrasound before and after wheelchair basketball or quad rugby. The average diameter of the tendon was calculated as well as the echogenicity ratio (the pixel intensity ratio of the biceps tendon to a reference just superficial to the tendon sheath).

SETTING

National Veterans Wheelchair Games in 2004 and 2005.

PARTICIPANTS

Forty-two subjects who participated in wheelchair basketball or quad rugby at the Veterans Games.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Biceps tendon diameter and biceps echogenicity.

RESULTS

The echogenicity ratio of the tendon significantly decreased from 1.97 to 1.73 after the event (P=.038). The diameter of the biceps tendon increased from 4.60 to 4.82 mm (P=.178). Also, it was found that the change in tendon diameter positively correlated with the time of play (P=.004).

CONCLUSIONS

Acute changes in biceps tendon properties after exercise were found and likely represent edema, a first sign of overuse injury. The significance of continuous activity was shown by the fact that subjects who had more playing time showed a larger increase in tendon diameter.

Stroke pattern and handrim biomechanics for level and uphill wheelchair propulsion at self-selected speeds

OBJECTIVES

To investigate the natural stroke patterns of wheelchair users pushing on a level surface, to determine if users adapt their stroke patterns for pushing uphill, and to assess whether there are biomechanic advantages to one or more of the stroke patterns.

DESIGN

Case series.

SETTING

Biomechanics laboratory.

PARTICIPANTS

Twenty-six manual wheelchair users with a spinal cord injury.

INTERVENTION

Subjects pushed their own wheelchairs at self-selected speeds on a research treadmill set to level, 3 degrees , and 6 degrees grades. Stroke patterns were measured using a motion capture system. Handrim biomechanics were measured using an instrumented wheel.

MAIN OUTCOME MEASURES

Stroke patterns were classified for both level and uphill propulsion according to 1 of 4 common classifications: arcing, semi-circular, single-looping (SLOP), and double-looping (DLOP). Biomechanic outcomes of speed, peak handrim force, cadence, and push angle were all compared across stroke classifications using an analysis of variance.

RESULTS

Only 3 of the 4 stroke patterns were observed. None of the subjects used the semi-circular pattern. For level propulsion, the stroke patterns were fairly balanced between arcing (42%), SLOP (31%), and DLOP (27%). Subjects tended to change their stroke pattern for pushing uphill, with 73% of the subjects choosing the arcing pattern by the 6 degrees grade. No statistically significant differences were found in handrim biomechanics or subject characteristics across stroke pattern groups.

CONCLUSIONS

Wheelchair users likely adapt their stroke pattern to accommodate their propulsion environment. Based on the large percentage of subjects who adopted the arcing pattern for pushing uphill, there may be benefits to the arcing pattern for pushing uphill. In light of this and other recent work, it is recommended that clinicians not instruct users to utilize a single stroke pattern in their everyday propulsion environments.

Effects of circuit resistance training on fitness attributes and upper-extremity pain in middle-aged men with paraplegia

OBJECTIVE

To examine the effects of circuit resistance exercise (CRT) training on muscle strength, endurance, anaerobic power, and shoulder pain in middle-aged men with paraplegia.

DESIGN

Repeated testing.

SETTING

Academic medical center.

PARTICIPANTS

Seven men (age range, 39-58y) with motor-complete paraplegia from T5 to T12 and confirmed shoulder pain occurring during daily activities.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Subjects underwent a 4-month CRT program using alternating resistance maneuvers and high-speed, low-resistance arm exercise. One-repetition maximal force was measured before training and monthly thereafter. Pretraining and posttraining peak oxygen uptake (Vo(2)peak) was measured by graded arm testing. Anaerobic power was measured before and after training using a 30-second Wingate Anaerobic Test. Shoulder pain was self-evaluated by an index validated for people with spinal cord injury (Wheelchair Users Shoulder Pain Index [WUSPI]).

RESULTS

Strength increases ranging from 38.6% to 59.7% were observed for all maneuvers (P range, .005-.008). Vo(2)peak increased after training by 10.4% (P=.01), and peak and average anaerobic power increased by 6% (P=.001) and 8.6% (P=.005), respectively. WUSPI scores +/- standard deviation were lowered from 31.9+/-24.8 to 5.7+/-5.9 (P=.008), with 3 of 7 subjects reporting complete resolution of shoulder pain.

CONCLUSIONS

CRT improves muscle strength, endurance, and anaerobic power of middle-aged men with paraplegia while significantly reducing their shoulder pain.

The relationship of shoulder pain intensity to quality of life, physical activity, and community participation in persons with paraplegia

BACKGROUND/OBJECTIVE

For persons with spinal cord injury (SCI), severe bodily pain is related to a lower quality of life. However, the effect of pain from a specific body region on quality of life has yet to be determined. The shoulder joint is a common site of pain among persons with SCI. Therefore, our purpose was to identify the relationship of self-reported shoulder pain with quality of life, physical activity, and community activities in persons with paraplegia resulting from SCI.

METHODS

Eighty participants with shoulder pain who propel a manual wheelchair (mean age: 44.7 years; mean duration of injury: 20 years; injury level T1-L2) completed the following questionnaires: Wheelchair User's Shoulder Pain Index, Subjective Quality of Life Scale, Physical Activity Scale for Individuals with Physical Disabilities, and Community Activities Checklist. Correlations between shoulder pain scores and quality of life, physical activity, and community activities were determined using Spearman's rho test.

RESULTS

Shoulder pain intensity was inversely related to subjective quality of life (r(s) =-0.35; P= 0.002) and physical activity (r(s) = -0.42; P < 0.001). Shoulder pain intensity was not related to involvement in community activities (r(s) = -0.07; P = 0.526).

CONCLUSIONS

Persons with SCI who reported lower subjective quality of life and physical activity scores experienced significantly higher levels of shoulder pain. However, shoulder pain intensity did not relate to involvement in general community activities. Attention to and interventions for shoulder pain in persons with SCI may improve their overall quality of life and physical activity.

Reduced Finger and Wrist Flexor Activity During Propulsion With a New Flexible Handrim

OBJECTIVE

To test the hypothesis that finger and wrist flexor activity is lower when pushing with a high-friction flexible handrim than with a standard uncoated handrim.

DESIGN

Case series.

SETTING

Biomechanics laboratory.

PARTICIPANTS

Twenty-four manual wheelchair users.

INTERVENTION

Subjects pushed their own wheelchairs on a research treadmill set to level, 3 degrees , and 6 degrees grades using both a standard uncoated handrim and a high friction flexible handrim. Propulsion speed was self-selected and held constant between handrim trials. Handrim order was randomized. Finger and wrist flexor muscle activity was measured at the forearm using surface electromyography.

MAIN OUTCOME MEASURES

Electromyographic data were rectified and normalized by each subject's maximum voluntary contraction. Total muscle exertion was determined by integrating the rectified signal over each push. Peak and total muscle exertion for each push were averaged across grade conditions and compared across handrims using a repeated measures t test.

RESULTS

The flexible handrim resulted in statistically significant reductions in both peak and total forearm muscle activation. Averaging across all subjects and grade conditions, peak muscle activation was reduced by 11.8% (P=.026) and overall muscle exertion was reduced by 14.5% (P=.016).

CONCLUSIONS

The flexible handrim was shown to require less finger and wrist flexor activity than a standard uncoated handrim for the same propulsion conditions.

Surface electromyography activity of trunk muscles during wheelchair propulsion

BACKGROUND

Trunk instability due to paralysis can have adverse effects on posture and function in a wheelchair. The purpose of this study was to record trunk muscle recruitment patterns using surface electromyography from unimpaired individuals during wheelchair propulsion under various propulsion speed conditions to be able to design trunk muscle stimulation patterns for actual wheelchair users with spinal cord injury.

METHODS

Fourteen unimpaired subjects propelled a test wheelchair on a dynamometer system at two steady state speeds of 0.9 m/s and 1.8 m/s and acceleration from rest to their maximum speed. Lower back/abdominal surface electromyography and upper body movements were recorded for each trial. Based on the hand movement during propulsion, the propulsive cycle was further divided into five stages to describe the activation patterns.

FINDINGS

Both abdominal and back muscle groups revealed significantly higher activation at early push and pre-push stages when compared to the other three stages of the propulsion phase. With increasing propulsive speed, trunk muscles showed increased activation (P<0.0001). Back muscle activity was significantly higher than abdominal muscle activity across the three speed conditions (P<0.0005), with lower back muscles predominating.

INTERPRETATION

Abdominal and back muscle groups cocontracted at late recovery phase and early push phase to provide sufficient trunk stability to meet the demands of propulsion. This study provides an indication of the amount and duration of stimulation needed for a future application of electrical stimulation of the trunk musculature for persons with spinal cord injury.