Exploring cycling and sports in people with a lower limb amputation: prosthetic aspects
Poonsiri, Jutamanee
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10.33612/diss.146256706
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Publication date: 2020
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Poonsiri, J. (2020). Exploring cycling and sports in people with a lower limb amputation: prosthetic aspects. University of Groningen. https://doi.org/10.33612/diss.146256706
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CHAPTER 9
This thesis focused on cycling participation of people with a lower limb amputation (LLA) and how to enable cycling particularly via understanding barriers, facilitators, predictors of cycling as well as the influences from their prostheses. In this chapter, the main findings, strengths, limitations and implications of this thesis will be discussed.
MAIN FINDINGS Cycling participation
Forty-seven percent of Thai people with a LLA cycled, versus 68% of Dutch people with a LLA. The cycling rate of Thai participants was in line with the highest cycling rate (48%) reported in the review in Chapter 3. Dutch participants cycled more than the highest percentage reported in Chapter 3 and sports participation reported in a previous review (11% to 60%) (1). The percentage of Dutch participants (64%) who cycled before a LLA was higher than that of Thai participants (43%), which might explain why Dutch participants cycled more after a LLA (2). Moreover, the Netherlands is known as the cycling nation par excellence, with more bicycles (23 million) than inhabitants (17 million) (3), so it is to be expected that the majority of Dutch people continue to cycle after a LLA. Thai and Dutch people with a LLA cycled for the following reasons: health (e.g., increase or maintain their muscle strength and physical health), transport, and recreation (e.g., have fun and relax). The majority of participants who cycled in both countries initiated cycling by themselves after a LLA. When cyclists were asked about their reasons for cycling in the last 6 months, Dutch cyclists mainly cycled for recreation (79%) and transportation purposes(61%). For Thai cyclists this was 68% and 47%, respectively. Thai cyclists mostly cycled on quiet roads (49%). Approximately 18% cycled on bicycle lanes (on-road), 14% on pedestrian paths, and 8% on bicycle paths (off-road). Dutch cyclists cycled mainly on bicycle lanes (85%) and quiet roads (81%). Both Thai and Dutch cyclists mostly cycled to visit shops and friends. This finding corresponds with a report from the Dutch government, which showed that cycling accounted for 27% of all transportation modes and that leisure was the main reason for cycling (37%), followed by work (24%), study (20%), shopping (13%), and other reasons (6%) (3).
In both countries, cyclists mostly cycled alone and no more than once a day (Thai: 91%, and Dutch: 75%). Approximately 17% of Thai cyclists also cycled with family, whereas 61% of Dutch cyclists cycled with family. A difference between Thai and Dutch cyclists was also found when comparing the distances covered during cycling for transportation and recreation. Thai cyclists cycled for 2 to 3 kilometers per ride and Dutch cyclists 5 to 14 kilometers per ride. The types of bicycles primarily used in both countries by cyclists (grandma bikes in
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Thailand versus electric bikes in the Netherlands) may account for the shorter distances covered by Thai people (3).
Regarding reported barriers to cycling (Chapters 4 and 5), Thai cyclists more often reported an inappropriate built environment (15% of Thai cyclists; and 9% of Dutch) and lack of safety (15 % of Thai and 4% of Dutch). For Thai cyclists, pollution was a barrier (5%), and a clean environment was a facilitator (22%). In the Netherlands, these specific environmental factors, both Thai and Dutch cyclists indicated that appropriate environmental factors were important facilitators for starting or continuing cycling (22-37%). Consequently, Thai cyclists may have encountered more barriers related to pollution, safety, and an unsuitable built environment than Dutch cyclists. This, in turn, might explain why Thai people cycle shorter distances and predominantly cycle on quiet roads.
Facilitators, barriers, and predictors of cycling with a LLA
The findings of the review reported in Chapter 3 suggested that socioeconomic, personal, and environmental factors, as well as factors related to prostheses and bicycles, influence cycling after a LLA. Younger age, a longer length of time since a LLA, and a more distal level of a LLA were positively associated with mobility, including cycling in people who had undergone a LLA due to trauma (4,5) (Chapter 3). However, Chapter 4 showed no differences between age and length of time since a LLA between Thai cyclists and non-cyclists. Although Dutch cyclists were younger and had undergone a LLA longer ago than non-cyclists, neither younger age nor a longer length of time since a LLA predicted cycling in Dutch people with a LLA (Chapter 5). Results in Chapters 4 and 5 provided cycling predictors of Thai and Dutch participants.
Predictors of cycling participation
Cycling prior to a LLA (Thai study)
In Thai participants, cycling before a LLA was found to increase the likelihood of cycling after a LLA. In line with previous studies, a history of sports participation before a LLA increased the likelihood of sports participation after a LLA (2,6). Similar to other studies in people with physical disabilities (2,7–9), non-cyclists rated significantly higher on lack of cycling skills /knowledge on how and where to cycle than cyclists.
Socioeconomic status- higher income (Thai study)
Socioeconomic factors affect individuals differently. In Chapter 3, it was reported that people with a LLA in India cycled predominantly for transportation
purposes (4), probably because cycling is cheaper than other forms of transport in India. In contrast, Thai people with a higher income were more likely to cycle (Chapter 4). Because the most common bicycles used by Thai people with a LLA were ordinary utility bicycles or grandma bicycles, and because the prostheses had been given for free, an explanation for this difference could be that these participants had a more active lifestyle. Other studies have also found a positive association between higher income and physical activity (PA) (10). This is consistent with the report of Thai cyclists on their ability to pay for the costs of prosthesis repair or maintenance (Chapter 6). As not having an appropriate prosthesis/bike was the third most frequently reported barrier by Thai non-cyclists (19%), people with a higher income may be in a better position to seek prosthesis adjustments (11,12).
A higher number of facilitators (Thai and Dutch studies)
In general, cyclists reported more frequently on facilitators and less frequently on barriers than non-cyclists. The most often reported facilitators by both cyclists and non-cyclists were related to perceived health benefits and positive attitudes toward cycling. Likewise, the top two categories of barriers reported by cyclists and non-cyclists in both studies concerned negative attitudes toward cycling (no motivation, no time, no cycling benefits, afraid of being injured) and health issues (no energy, pain, wound, discomfort, poor health condition).
Perceived barriers were found to be negatively associated with participation in PA in able-bodied Thais (13). Other studies found that disabled persons who were regularly active perceived benefits from engaging in PA such as improvement of health and physical strength and having fun (2,14–17). The Theory of Planned Behavior suggests that despite the presence of individual intention, individuals are unlikely to pursue a given type of behavior if more difficulties are perceived than benefits (perceived behavioral control)(18). Using a dynamic foot (Thai and Dutch studies)
Both Thai and Dutch surveys showed that using a foot with more ankle range of motion (in the sagittal plane) than a SACH foot, for example, a dynamic foot, increased the likelihood of cycling after a LLA. People with a higher functional level who are able to walk independently with varied cadences on varied types of terrains are generally prescribed a dynamic foot instead of a SACH foot (19). Amputation cause (Thai study) and underlying diseases (Dutch study)
Having undergone a LLA due trauma and having an intact knee joint predicted a higher likelihood of cycling in Thai (Chapter 4). The presence of other
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underlying diseases or comorbidities besides the cause of a LLA predicted a lower likelihood of cycling in Dutch people (Chapter 5). People with a LLA and comorbidities such as diabetes walked less than healthy able-bodied people (20,21). Also, people with a transtibial amputation (TTA) were more active than people with a transfemoral amputation (TFA) (1,4). These predictors suggest that cyclists are likely to have a higher functional level than non-cyclists.
The results of Thai and Dutch surveys were summarized using the International Classification of Functioning, Disability and Health (ICF) framework in Figure 1.
Figure 1. ICF conceptual model of factors influencing cycling participation after a lower limb amputation
Lower limb prostheses for physical activities, recreational cycling, transportation, and sports
The case reports described in Chapter 2 showed that people with a bent-knee prosthesis were able to walk and to participate in daily, vocational, and recreational activities. Prosthesis fittings were possible in a person with a knee or hip flexion contracture beyond 25 degrees, although the cosmetic appearance of the prosthesis might be compromised. Bent prostheses were more cosmetic when a residual limb was short although a longer residual limb
has more muscle volume and a longer lever arm controlling the prosthesis. Nevertheless, given that people participate less in PA after a LLA, having the contracture could make PA even more difficult for them. Some persons used crutches when walking with their prosthesis (23,24). Walking ability is a predictor of successful ambulation with the prosthesis (24), and outdoor activities require standing balance and physical strength to adjust to different environmental conditions and prevent falls (25). For that reason, it is important that the treatment of contractures takes place parallel to the prosthesis fitting to enable future participation in indoor and outdoor activities.
As reported in Chapters 4 and 5, people received a prosthesis for walking and used it for cycling. Thai people were fitted with conventional prosthetic components and designs, including a SACH foot, patellar tendon bearing or quadrilateral hard socket, foam liners, or mechanical knee joint. Nevertheless, they were able to use their daily prosthesis for cycling. Only a small percentage adapted their prosthesis for cycling or did not use a prosthesis during cycling. Dutch participants reported more diverse designs and prosthetic components than Thai participants, including a flexible/hard socket, pin/sleeve/seal-in liner, or pneumatic/hydraulic /microprocessor knee. One component that affected the likelihood of cycling after a LLA in Chapters 4 and 5 was the prosthetic foot. Thai participants reported using a SACH foot the most, but this design decreased the likelihood of cycling after a LLA. This was also found to be the case for Dutch participants. Recreational cyclists applied less force to the pedal compared with athlete cyclists. This means the force they apply may not be enough to deform the foot and cause energy return from the dynamic foot (26,27). Therefore, a prosthetic foot does not directly influence the performance of recreational cyclists but rather reflects the functional level suitable for the use of a dynamic foot (19).
For athletes, however, specially designed prostheses such as sports feet can directly influence their performance which is the most important factor for them. In Chapter 7, almost all participants used a prosthetic sports foot for running-related sports. Three dimensions were analyzed in this chapter: use, provision process, and cosmetics of the prosthetic sports feet. Use was found to be the most important dimension.
Satisfaction with prosthesis and service
In Chapter 6, the results of a survey evaluating the satisfaction of Thai cyclists and non-cyclists with the prosthesis and with the prosthesis service were discussed. Overall, participants who cycled for recreation or transport in Thailand and the Netherlands were satisfied with their prosthesis and the service provided. There were no differences between Dutch cyclists and
non-9
cyclists regarding the scores on satisfaction (Chapter 5). However, Thai cyclists were more satisfied with the prosthesis than non-cyclists. Factors predicting higher prosthesis satisfaction scores in Thailand were: not using gait aids, being employed or retired, being amputated below the knee, having no or basic education, and having had the prosthesis supplied by the hospital. Receiving a prosthesis from hospitals, including Phramongkutklao, Lerdsin, Siriraj, and Veterans General Hospitals, was found to increase prosthetic satisfaction when compared with receiving a prosthesis from a mobile unit. This difference in prosthesis satisfaction may be explained by the different skills possessed by technicians or prosthetists in each facility or the inability of the mobile unit to conduct a follow-up and adjust problems with the prosthesis later on. One factor predicting a higher service satisfaction was not using additional gait aids besides the prosthesis. In line with several other studies (12,28–32), these results suggest that mobility, prosthesis use and adjustment, and socioeconomic status influence satisfaction with the prosthesis.
In Chapter 7, athletes rated their satisfaction and the relative importance of different dimensions regarding their prosthetic sports foot. Athletes were satisfied with the use of their foot and the service provided, but they were not satisfied with the process prior to the provision of the foot. Performance of the foot was key to determining satisfaction with the foot. Cosmesis was unimportant for the athletes (33).
STRENGTHS
This thesis is the first to explore factors related to cycling participation in Thailand and the Netherlands in people with a LLA. The thesis evaluated cycling participation in people with a LLA and provided insights into cycling reasons, facilitators, barriers, and predictors. Prostheses used were also surveyed and its association with cycling participation and satisfactory were evaluated.
The results showed that cycling was integrated in the daily life of several participants. Consequently, cycling is a promising way to promote health in people with a LLA. A better understanding of the facilitators, barriers, and predictors of cycling helps clinicians with stimulating and facilitating cycling in this population. The insights on the type of prosthesis used, the satisfaction with the prosthesis, and the satisfaction with the service provided offer important information on how these aspects can be improved to meet the needs of the individual when it comes to participation in cycling or any other sport. Clinicians should tailor the prosthesis and training to meet the needs of the PA the individual wishes to pursue.
LIMITATIONS
Chapters 2 and 3 were systematic reviews, but most of the included studies had small sample sizes. In Chapter 8, a study (34) included in Chapter 3 was critically analyzed. At first, a large sample size seemed to be included in that study. However, it was found that many participants had been reanalyzed more than once. Chapter 2 included case reports that were mostly published before 2000, so the results may not represent the latest prosthetic technologies. Moreover, authors may have chosen to only publish case reports on successful fittings and to refrain from publishing unsuccessful prosthesis fittings. In Chapter 3, the reported effects of types of prostheses or bicycles on cycling were mostly limited to competitive cyclists. In addition, criteria for classifying participants participating in sports or other physical activities varied between the included studies. In Chapters 4 and 6, the majority of participants were veterans, and in Chapter 5 the majority of Dutch participants had undergone a LLA due to trauma. Given that these participants may not represent the entire population of people with a LLA in Thailand and the Netherlands, generalization of study results might be limited.
In the results of the survey held in Thailand (Chapters 4 and 6), socially desirable answers may be present because participants filled out the questionnaire at the prosthetic facility. This means they might have been hesitant to rate their true satisfaction. Thai participants did not complete all parts of the questionnaire, especially the last part on prosthesis satisfaction and satisfaction with the service provided. Some participants may not have been able to rate the satisfaction with the prosthesis and service because it was the first time they received a prosthesis from that facility. Other participants may have underrated their financial abilities out of fear of not obtaining financial support for their prosthesis. Although the survey in the Netherlands (Chapter 5) had fewer problems with socially desirable answers because the participants filled out the questionnaire at home, participants may have incorrectly reported on the type of their prosthetic component. In the Thai survey, prosthetists filled out the technical data on prosthetic parts for the participants. In both surveys, cycling duration or frequency may not have been accurately reported due to recall bias (35) and may also have been influenced by the season in which the questionnaires were completed (36). Moreover, Dutch participants may have responded to the invitation to participate in the study because they already cycled, resulting in an overestimation of cycling participation.
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IMPLICATIONS FOR THE REHABILITATION TEAMChapter 2 showed that a successful prosthetic fitting is possible for people with a severe flexion contracture of the knee or hip joint. Therefore, clinicians should not solely base their prescription decision on the information provided in textbooks. They should also take other factors into account, including a person’s desire to participate in PA, recreational activities, or sports. For instance, a daily prosthesis seems adequate for cycling for recreation or transportation (Chapters 4 and 5). However, athletes are more likely to benefit from the use of a specialized prosthesis for sports (Chapter 7).
Perceiving more facilitators than barriers could affect the decision of people whether to participate in cycling or not. Clinicians should find ways to increase perceived facilitators and reduce perceived barriers. Cycling training can be included in the rehabilitation program, so as to increase cycling knowledge, skills, and confidence of individuals, especially for persons who have never cycled before a LLA. Health-related barriers such as pain or discomfort could be the result of using an inappropriate prosthesis. These barriers may be reduced by adapting a daily prosthesis to match with the desired PA (Chapters 4 and 5). For instance, people with a Van Nes rotationplasty who could not flex their knee, were found to benefit from replacing the socket with shoes for cycling (Chapter 3). For a competitive cyclist with a TTA, using a stiff foot can reduce cycling asymmetry (Chapter 3). Prescribing a dynamic foot to people who are physically more active may also stimulate prosthesis use during participation in other forms of PA. When persons are able to use the prosthesis more because it suits with their function and lifestyle, an increase in overall satisfaction with the prosthesis and service could be achieved.
In Chapter 7, it became clear that for athletes the most important dimension of the prosthetic sports foot was its use, which was directly influenced by the performance. For this specific group, clinicians should establish how to meet the desired sports performance level and improve the process prior to the provision of the sports feet. This can be achieved by increasing the support given to athletes during rehabilitation and training, by organizing try-out sessions for different types of prosthetic sports feet, and by increasing accessibility of the prosthetic sports feet.
IMPLICATIONS FOR CYCLISTS WITH A LLA
Several cyclists had cycled before a LLA, but cycling with a prosthesis after a LLA may require some additional training or a prosthesis/bicycle adaptation. People with a LLA who want to cycle are advised to seek help or suggestions from the rehabilitation physician, prosthetist, or physical therapist. Training on a
stationary bicycle or an ergometer can increase cycling skills. Moreover, cycling exercises can improve cardiopulmonary fitness, which is often negatively affected by the comorbidities that some people with a LLA have (37).
Daily prostheses are often used for recreational cycling and seem to function adequately in this respect. Still, cyclists can benefit from adaptations to the prosthesis or bicycle (Chapters 3, 4, 5), and are advised to consult a prosthetist and/or a bicycle maker. In the surveys, cyclists described some adaptations. For example, in case of a knee joint motion limited by a socket border or knee joint component, cycling with the intact limb was mentioned as a solution. Other cyclists adjusted their bicycle by rising the seat, shortening a crank, or using a hinged crank on the prosthetic side. Some cyclists mentioned their foot slipped off the pedal. Adding a foot strap or using a cycling shoe may eliminate this problem. However, it may not be feasible to have two pairs of shoes. Moreover, clipping the foot to the pedal can be dangerous when one needs to get off the bike quickly in case of an emergency. For competitive cyclists, using a specific cycling prosthesis can increase cycling performance (Chapter 3). It is crucial to communicate with the clinicians the desire to use the prosthesis for sports and goals in order to get a suitable prosthesis (Chapter 7). Chapters 4 and 5 showed that cyclists in both countries mostly use a grandma bicycle. Many Dutch cyclists also used an electric bicycle or a women’s bicycle, even though the majority of cyclists was male (Chapter 6). The women’s bicycle structure may facilitate getting on and off the bike with a prosthesis, and electric bicycles could reduce the amount of energy required to cycle and thereby increase cycling distance.
IMPLICATIONS FOR POLICYMAKERS
Many people with a LLA cycled for relaxation. A positive attitude to cycling was the most frequently mentioned facilitator to start cycling or continue cycling, and several participants reported that cycling is fun and healthy. Moreover, cycling can be part of social events or norms. In Thailand, cycling has been used to show the unity of the Thai and their love towards their father and mother as well as the King’s father and mother. In the Netherlands, a participant described the reason for cycling as a social norm: ‘…omdat iedereen fietst. In NL is fietsen net zoiets als lopen’ (...because everyone cycles. In the Netherlands, cycling is like walking). In a society, everyone, including people with a LLA, should be able to participate in social events equally. Persons who have undergone an amputation and do not possess a suitable bicycle or prosthesis may be hindered in participating in social activities.
The government should, therefore, create an environment that enables social inclusion of all people in society. This means providing accessible cycling
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or sports training facilities, cycling paths, funding for prosthesis modifications or sports prostheses, reimbursements or health coverage policies that cover travelling expenses to prosthetic facilities, and safety policies for all types of vehicles users. In addition, health promotion campaigns that increase a positive perception of cycling (e.g., cycling is sustainable, safe, fun, and healthy), financial incentives (e.g., vouchers for adjusting devices or free bicycles for people with an amputation), and access to information (e.g., training programs, bicycle or prosthetic repairs, and cycling routes) may encourage people with a LLA to cycle.
IMPLICATIONS FOR FUTURE RESEARCH
Future studies should evaluate the long-term effects of bent prosthesis use, for example, excessive pressure on the tibia, gait asymmetries, gait deviations, and energy consumption. This information can explain why prosthesis fittings can be difficult for people with a severe hip or knee contracture and help clinicians to base their decision-making on scientific evidence rather than the word “difficult” or clinical experience.
We found that many people cycled after a LLA and that cycling facilitators, barriers and predictors possibly reflect higher motivational and functional levels in people who cycle. To explore cycling motivation, researchers could interview cyclists on how social policies, attitudes, types of prostheses, or perceived facilitators or barriers affect their participation. An observational study that uses objective measures such as a pedometer could be used to explore the relationship between functional levels and cycling participation.
Most of the studies included in Chapter 3 on types of prostheses and bicycles were conducted in competitive cyclists with a TTA. Cycling asymmetries were often studied in competitive cyclists with a TTA, in whom the intact limb did more work than the prosthetic limb. Little research has focused on people who cycle for recreation and transport purposes, even though they make up the majority of people with a LLA. Future studies should examine the effects of cycling asymmetries on recreational cycling, including cycling distance and frequency.
In the Thai study (Chapter 4), people with a TTA cycled more than people with a TFA. An explanation for this difference could be that people with a TTA require less energy to perform the same kind of activity (38). Understanding how the level of a LLA affects cycling efficiency or energy consumption could be of interest to prosthetists and engineers when choosing or designing prostheses and bicycles for cyclists.
The cycling predictors described in Chapters 4 and 5 were based on the results of the survey studies. In both studies, it was found that a prosthetic foot with more ankle range of motion than a SACH foot increased cycling likelihood.
To determine whether prosthetic feet reflect the functional levels rather than affecting cycling performance, future studies should evaluate kinematics and kinetic differences when using a SACH, single axis, or dynamic foot in recreational cycling.
Following the results of cycling frequency and duration in Chapters 4 and 5, Thai cyclists who cycled once a day for at least 20 minutes would meet the PA recommendation for health benefits (39,40). Dutch cyclists would all meet this recommendation when using grandma bicycles. It is not certain how much energy is expended when cycling on an electric bicycle. Furthermore, there is no baseline information on how much people with a LLA consumed energy during cycling when compared with the resting metabolic rate and whether this expenditure is comparable with that of able-bodied individuals. Future studies could research differences in energy expenditure while cycling between people with a LLA and able-bodied people.
For the reasons mentioned above, our future study aims to analyze cycling gross efficiency, pedaling power, and hip, knee, and ankle kinematics in adults with a TTA in comparison with able-bodied adults. As adaptations of the prosthesis or bicycle can influence cycling, we will also determine the effect of cyclists’ positions (different foot positions and seat heights).
CONCLUSION
People with a LLA mostly cycled for health, recreation, and transport. Although they acknowledged the health benefits of cycling, some participants did not cycle themselves. Therefore, the involved professionals should explore how they can increase the number of facilitators and reduce the number of barriers related to cycling. Satisfaction with both the prosthesis itself and prosthetic service could be achieved through gaining a better understanding of how the individual wishes to use the prosthesis. In people who have contractures, comorbidities or a lower functional level, training and improving walking ability may facilitate them to participate more in PA, including cycling. Policymakers should initiate campaigns, provide financial incentives, and create appropriate environments for promoting cycling for health benefits and social inclusion of people with a LLA. Future studies should examine the effects of a bent prosthesis, cyclists motivation and functional levels as well as cycling efficiency in people with a LLA.
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