developed successfully; this FAW can be driven by both legs and steering wheelchair by unaffected arm. It provided alternative means to achieve mobility for hemiplegic patients who can not ambulate independently.
With regard to the speed of FA/ LW is significant higher compare to the MW, the brake is necessary [9]. However, patients can not reduce the speed of FA/ LW by attrition rear wheels by both arms like manual wheelchair. Therefore FA/ LW equipped a brake lever on the steer lever and two set of clipper brakes on each rear wheels. This safety design allows the patients to reduce speed of wheelchair and to prevent wheelchair from deviation.
In order to reduce turning radius of FA/ LW, allowing wheelchair to be propelled by patient in reverse is necessary. Reverse function was not provided in most leg propelled wheelchair, it made certain maneuvers difficult or impossible for leg-propelled wheelchairs such as three-point turn maneuver [19]. The FA/ LW equipped with a switch mounted on the grip of steer lever. As patient operating switch, the clutch of gear set was shafted to mesh different gear and causing direction change to forward or backward. This easy and convenient design allows patients to reverse FA/
LW in a narrow space. In addition, it is necessary to equip a neutral position. It can move wheelchair every where by caretaker when legs of patients are fatigue.
Eight hemiplegic patients were recruited to attend clinical evaluation. The results of evaluation revealed that FA/ LW is significant better than MW on the finiah time of maneuverability. Moreover, the PCI of LW and FAW is about 57.3 and 59.5% lower than MW, respectively. It meant that FA/ LW had higher propelling efficiency than that of MW. The MAS of affected leg reduced significantly after propelling FA/ LW, showed that the muscle tone of affected leg decreased. With regard to the results of clinical evaluation, FA/ LW were significant better than MW at maneuverability, propelling efficiency and muscle tone decreasing.
The maneuverability of the FA/ LW was superior to that of the MW in finishing the same course. It might be easier for hemiplegic patients to steer the FA/ LW by arm
than to control direction of the MW by the unaffected leg. For stroke patients, compare with wheeling MW which needed highly coordination ability of leg and arm to finish the course, FA/ LW only needed to propelling by legs and steering by arm. Accordingly, this operation manner provided better maneuverability than MW.
Hemiplegic patients using the FA/ LW in this study showed more efficient than to wheel the MW with the unaffected arm and leg. The present study revealed the same trends with the previous research [9], the efficiency of lower extremity-propelling wheelchairs were better than MW. The relatively large muscles of lower extremity had greater oxidative capacity, greater motor unit recruitment, differences in fibre type, and increased ability to generate tension. Therefore, there was higher efficiency for leg propelling compared with arm wheeling in the present study. The arm wheeling pattern was more complex and discontinuous than leg cycling. The extra energy loss would arise in the recovery phase due to acceleration and deceleration of the arms [20] [21].
Besides, It might be a better way to maintain/ improve cardiopulmonary function by strengthening large muscle groups of lower extremity than strengthening small muscle group of upper extremity [22] [23].
Many researches also pointed out that when stroke patients propelling manual wheelchair, it will induce contralateral abnormal muscle tone because of asymmetrical contribute situation [24] [25]. In clinical evaluation, although MAS of affected leg did not change significantly, but there were still two patients whose muscle tone of affected leg is increased. On the contrary, muscle tone of post-exercise was decrease significantly than pre-exercise in FA/ LW. The possible reason for decrease muscle tone of leg in FA/ LW was that cycling exercise is a multi-joint, coordination and symmetrical bilateral lower extremities exercise. It could provide passive stretch exercise for joints of lower extremity to reduce abnormal muscle tone and stretching ankle plantarflexors repeatly could reduce not only the elasticity of the hypertonic muscles, but also their viscosity in the stroke patients [26] [27].
6. Conclusion
The results of cardiopulmonary fitness demonstrated that there was no significant difference in with or without FES. The reason might stem from the same total workload and distance in propelling LW and FAW. Besides, the results of muscle tone demonstrated that there was no significant difference between with FES (FAW) and without FES (LW). The electrical stimulation for spasticity was base on mechanisms of facilitating Renshaw cell recurrent inhibition, antagonist reciprocal inhibition, and cutaneous sensory habituation. However the effect of electrical stimulation included biomechanical and neurological factors. The biomechanical effects of LW and FAW were almost the same. The benefit of solely electric stimulation to reduce spasticity is limited, but in clinical practice may be enhanced when movement is allowed during stimulation (FAW). Most contributions might came from repeated motion.
In the present study, the affected leg of hemiplegic patient was afforded low intensity stimulation current in FAW to achieve cycling motion exercise instead of passive driven by affected leg. However, the output force of the affected and the unaffected legs were not measured and the neurological factors were not clear in the present study. We can’t discriminate the difference of cardiopulmonary fitness and muscle tone between LW and FAW. In the future, more participants should be choosing to join the evaluation to realize the long term effect of FES.
References
1. Michael KM, Allen JK, Macko RF. Reduced ambulatory activity after stroke: the role of balance, gait, and cardiovascular fitness. Arch Phys Med Rehabil 2005; 86:
1552-1556.
2. Macko RF, Smith GV, Dobrovolny CL, Sorkin JD, Goldberg AP, Silver KH.
Treadmill training improves fitness reserve in chronic stroke patients. Arch Phys Med Rehabil 2001; 82: 879–884.
3. Meek C, Pollock A, Potter J, Langhorne P. A systematic review of exercise trials post stroke. Clin Rehabil 2003; 17: 6–13
4. MacKay-Lyons MJ, Makrides L. Exercise capacity early after stroke. Arch Phys Med Rehabil 2002; 83: 1697-1702.
5. Mayo NE, Wood-Dauphinee S, Ahmed S, Gordon C, Higgins J, McEwen S, Salbach N. Disablement following stroke. Disabil Rehabil 1999; 21: 258-268.
6. Ryan AS, Dobrovolny CL, Smith GV, Silver KH, Macko RF. Hemiparetic muscle atrophy and increased intramuscular fat in stroke patients. Arch Phys Med Rehabil 2002; 83: 1703-7.
7. Kirby RL, Adams CD, MacPhee AH, Coolen AL, Harrison ER, Eskes GA, Smith C, MacLeod DA, Dupuis DJ. Wheelchair-skill performance: controlled comparison between people with hemiplegia and able-bodied people simulating hemiplegia.
Arch Phys Med Rehabil 2005; 86: 387-393.
8. Kirby RL, Ethans KD, Duggan RE, Saunders-Green LA, Lugar JA, Harrison ER.
Wheelchair propulsion: descriptive comparison of hemiplegic and two-hand patterns during selected activities. Am J Phys Med Rehabil 1999; 78: 131-135.
9. Makino K, Wada F, Hachisuka K, Yoshimoto N, Ohmine S. Speed and physiological cost index of hemiplegic patients pedaling a wheelchair with both legs. J Rehabil
13. Petrofsky JS, Phillips CA, Heaton HH. Bicycle ergometer for paralysed muscle. J Clin Eng 1984; 9: 13-19.
14. Stein RB, Chong SL, James KB, Bell GJ. Improved efficiency with a wheelchair propelled by the legs using voluntary activity or electric stimulation. Arch Phys Med
Rehabil 2001; 82: 1198-1203.
15. Dallmeijer AJ, Zentgraaff IDB, Zijp NI, van der Woude LHV. Submaximal physical strain and peak performance in handcycling versus handrim wheelchair propulsion.
Spinal Cord 2004; 42: 91-98.
16. Tsai KH, Yeh CY, Lo HC. Applications of concurrent systematic design on assistive technology-- A new wheelchair design for stroke patient. FMBE Proceedings EMBEC’05 2005; 11: 28.
17. Philips CA. Functional electrical stimulation: technological restoration after spinal cord injury. New York: Springer Publishing, 1991.
18. Chen HY, Chen SC, Chen JJ, Fu LL, Wang YL. Kinesiological and kinematical analysis for stroke subjects with asymmetrical cycling movement patterns. Journal of Electromyography and Kinesiology 2005; 15: 587-595.
19. Bloswick DS, Erickson J, Brown DR, Howell G, Mecham W. Controllability and usability analysis of three knee-extension propelled wheelchairs. Disabil Rehabil 2003; 25: 197-206.
20. Woude LHV et al. Biomechanics and physiology in active manual wheelchair propulsion. Med Eng Phys. 2001; 23: 713-733.
21. Hintzy F, Tordi N, Perrey S. Muscular efficiency during arm cranking and wheelchair exercise: a comparison. Int J Sports Med. 2002; 23: 408-414.
22. Garber CE, Monteiro R, Patterson RB, Braun CM, Lamont LS, A comparison of treadmill and arm-leg ergometry exercise testing for assessing exercise capacity in patients with peripheral arterial disease. Journal of Cardiopulmonary Rehabilitation 2006; 26: 297-303.
23. Bauer TA, Brass EP, Nehler M, Barstow TJ, Hiatt WR, Pulmonary V O2 dynamics . during treadmill and arm exercise in peripheral arterial disease. J Appl Physiol 2004;
97: 627-634.
24. Barrett JA, Watkins C, Plant R. The COSTAR wheelchair study: a two-centre pilot study of self-propulsion in a wheelchair in early stroke rehabilitation. Clin Rehabil 2001; 15: 32-41.
25. Pomeroy VM, Mickelborough J, Hill E, Rodgers P, Giakas G, Barrett JA. A hypothesis: self-propulsion in a wheelchair early after stroke might not be harmful.
Clin Rehabil 2003; 17: 174-180.
26. Yeh CY, Chen JJ, Tsai KH. Quantitative analysis of ankle hypertonia after prolonged stretch in subjects with stroke. J Neurosci Methods 2004; 137: 305-314.
27. Yeh CY, Chen JJ, Tsai KH. Quantifying the effectiveness of the sustained muscle stretching treatments in stroke patients with ankle hypertonia. Journal of Electromyography and Kinesiology 2006 (available online).