Approximately 185,000 people each year undergo limb amputation in the United States.1 A number of limb-threatening conditions necessitate amputation, such as peripheral artery disease, diabetes mellitus, trauma, and cancer.2 Lower-limb amputation (LLA) accounts for 66% of all amputations in the United States.1 Lower-limb amputation poses a daunting challenge to productive living, as people with LLA often experience participation restrictions in performing work-related, social, and general physical activities.3 Because of the restrictions, those with LLA are likely to be more sedentary, placing them at a heightened risk for developing chronic conditions such as cardiovascular disease, osteoarthritis, back pain, and obesity, which result in poorer long-term health and functional outcomes.4–7
Physical activity (PA) is one modifiable risk factor that can reduce the likelihood of secondary health conditions.8 Along with improving the risk for secondary health conditions, PA improves cardiorespiratory fitness, muscular strength and endurance, balance, body image, and even cognition.9,10 For people with LLA, a number of clinical factors contribute to major life participation restrictions. These factors include impairments in muscular strength, balance, time since amputation, and the anatomic level of amputation.11 With the realization that PA can improve long-term health outcomes and functional impairments associated with participation restrictions, it is imperative that people with LLA maximize PA participation. However, people with LLA do not sufficiently participate to elicit these benefits.12 One possible reason is that people with LLA reported that PA habits after amputation are drastically different from their PA habits before amputation.12
For people with LLA, differences between preamputation and postamputation PA habits are related to a number of potential barriers to participate. These potential barriers include 1) body structure and function impairments; 2) activity limitations; and 3) personal and environmental factors. Several structural impairments are commonly associated with LLA, such as heterotrophic ossification (HO), soft tissue injuries in the residual limb, and phantom limb pain syndrome.13–15 People with LLA experience functional impairments, such as decreased aerobic capacity, muscle atrophy in the residual limb, and muscle strength difference in their lower limbs.16–18 In addition, skin issues presenting as pressure ulcers and calluses are reportedly common problems and have been related to frequent yet improper prosthetic use.19 Activity limitations such as standing for long periods, walking long distances, and taking care of household responsibilities may contribute to PA participation restrictions.2 Potential personal and environmental factors related to physical access to social events may also mediate participation.20
Restrictions in PA participation for people with LLA are commonly reported.2 The severity of these restrictions differs based on the anatomic location (e.g., upper vs. lower limb) and level of amputation (e.g., transtibial vs. transfemoral).2 The type of amputation procedure performed could also influence PA participation. For example, the osteomyoplastic procedure posits to provide people with LLA a “stable, dynamic limb that allows for efficient rehabilitation, long-term health, and easier, more functional prosthetic fittings” when compared with the traditional method of amputation.21(p7) The osteomyoplastic, or “Ertl,” procedure differs from conventional LLA techniques as it creates a “bone bridge” between the tibia and fibula while also reconstructing surrounding musculature.21 Currently, there are no studies investigating the impact of surgical procedure on the barriers and facilitators to PA participation for people with LLA. Thus, the purpose of the present study was to investigate barriers and facilitators to PA participation for men with transtibial osteomyoplastic amputation (TOA).
The present study is an observational, qualitative research design using thematic analysis.
Inclusion criteria were as follows: 1) English speaking; 2) “working age” men (18–64 years); 3) with unilateral TOA; 4) at least 1 year after amputation surgery; and 5) who actively use a prosthetic limb. Exclusion criteria were as follows: 1) significant medical (cardiorespiratory, peripheral vascular, neuromuscular, inflammatory) conditions that might be contributing factors to lack of PA other than amputation through self-report methods; 2) bilateral LLA; 3) regular, frequent, or sustained use of walking assistive devices (cane, walker, crutches, etc); 4) inability to independently give formal consent; and; 5) the presence of any vision or hearing impairment that prohibit communication. Recruitment of the participants occurred through purposive sampling of patients at both an orthopedic surgery practice specializing in osteomyoplastic amputation procedures and a prosthetics clinic within a university hospital system. Purposive sampling allows for the selection of participants that will provide in-depth, information-rich interviews.22 This study was approved by the Pittsburg State University (Pittsburg, KS, USA) Institutional Review Board for protection of human participants.
Personal, semistructured interviews were conducted to capture participants' opinions. Individuals meeting inclusion criteria were invited to participate in the study by either D.A.C. or C.P.D. All interviews were conducted by the same investigator (D.A.C.) to ensure reliability and accuracy of the data collected, and held either at a convenient location for the participant or by telephone. Each interview session began with informal conversation aimed at establishing a convivial rapport with the participant and facilitating a natural discussion, and opened with an overview of the study and a summary of the questions that would be asked. Recruitment and interviews continued until data saturation was achieved. Data saturation (i.e., the point when no new codes emerged from the data) was reached after the completion of seven interviews. Two more interviews were conducted to confirm data saturation. All interviews were audio recorded and then transcribed verbatim into word processing software (Word 2016, Microsoft, Inc; Redmond, WA, USA) for later analysis.
Immediately after each interview, the name of the participant was replaced by a study identifier (e.g., P2) representing the order in which they were interviewed. Before data analysis, D.A.C. developed a codebook for the organization of emergent codes from the data transcription. This codebook was divided into five categorical sections based on the International Classification of Functioning, Disability, and Health (ICF) and included body structure/functions, activities, participation, personal, and environmental factors. The use of the ICF in formatting the codebook was selected to enable the study investigators to readily categorize the emergent codes for subsequent analysis and reporting. After thematic data analysis, each investigator read the transcripts and generated emergent codes for each participant independent of D.A.C., who combined each investigator's emergent codes into one summary codebook per participant. After this, all investigators by consensus classified the emergent codes into themes acting as either barriers or facilitators within the distinct categories of the ICF. Rigor was established through triangulation between multiple analysts during each phase of data analysis and via the use of an audit trail throughout. Further, data analysis is enhanced through credibility of the research team that includes T.B.H., considered a content expert in qualitative research methods, and C.P.D., a physical therapist and researcher specializing in the population of individuals with amputation.
Nine men with unilateral TOA consented to participate in the study. Participant demographics of this study are provided in Table 1. Results are presented under the five ICF categories used during data analysis (i.e., body structure/functions, activities, participation, personal factors, and environmental factors) and identified whether the themes act as barriers or facilitators to PA. Representative quotes are used to illustrate the findings with substantial quotes being attributed to participants using their study identifier (e.g., P5, P8). As noted earlier, the use of the ICF model allows for both the categorization of codes and themes as well as visualization for the relationships between them. Figure 1 illustrates the facilitators and barriers to PA participation identified in the present study classified within the ICF framework.
BODY STRUCTURE/FUNCTION IMPAIRMENTS
Within this group of transtibial osteomyoplastic participants, minimal body structure impairment in the residual limb is reported. Traditionally, one could expect to see structural issues such as phantom limb pain, heterotopic ossification, and deep tissue injury (i.e., muscle or connective tissue injury) resulting from prolonged or improper prosthetic use and fit to act as barriers to PA participation.20–22 However, only minimal structural impairments in the residual limb were reported. The only reported structural impairment was limited to one case of phantom limb pain and two cases of mechanical pain in the knee joints within the intact limb. One participant noted that his lack of structural issues can be attributed to the type of amputation procedure he underwent: “I've had a good procedure done, the Ertl (i.e., osteomyoplastic) procedure, and I've got good residual limb health.” [P3]
Even with the minimal structural impairments, these participants still reported impairment in various body functions. Functional impairments that act as barriers to PA reported by these participants are prosthetic function, residual limb skin issues, low physical endurance, and low muscular strength. Prosthetic function was reported to change throughout the day. Participants reported that, as the day progresses, prosthetic fit changes, ultimately affecting comfort and function: “[The] prosthetic itself is fairly comfortable when you put it on, it is firm and it feels good and it doesn't bother you but as the day goes on and it compresses and shrinks your leg you either have to take it off or keep readjusting it. And even then, after you have readjusted, it does not feel like it did in the morning. It never gets that way again.” [P4] Some participants also reported that the function of the prosthesis differs, given the type of surface that they are on: “I have to be aware of the surface I'm on. Inclines are very, very difficult to negotiate as is rocky terrain.” [P1]
Additional issues reported concerning function of the residual limb were prolonged wearing of the prosthesis result in discomfort to the residuum skin: “The sleeve and the liner compresses your leg all day and first thing you want to do when you get home is take that off…[it's] a tingling or compression type feeling and it hurts really bad.” [P4] In addition, skin issues such as blisters and ingrown hairs in the residual limb are reported after prolonged PA, often resulting in the need to take time off from those activities: “[When] I'm working a blister up pretty good and so I might just have to sit down and say I'm not going do a darn thing.” [P5]
Low cardiovascular endurance is reported as a significant barrier to participation in PA at varying ranges of severity. Some participants reported difficulty walking moderate distances: “I can handle it [walking] around the house, not around the street for half a mile.” [P4] Others reported noticing fatigue toward the end of their day: “It gets to that point that my body is running out of energy.” [P7] One participant reported having to focus more effort on the maintenance of his cardiovascular endurance so that it did not become a barrier: “I try to run more than I did before I got amputated. [I] try to keep my cardio up, because my cardio goes away lot faster it seems like.” [P6]
Deficient lower-limb and core muscular strength was reported by one participant who expressed a desire to change: “ [I'm] weak and fat, but I've gotten the dumbbells out and I've been doing some exercises recently.” [P5] Conversely, one participant reported the development and maintenance of lower-limb strength as a facilitator to his mobility: “I do squats, leg lifts, and extensions—whatever I want to do. Actually that's what makes it easier to walk.” [P6]
Few limitations in functional mobility are reported for requirements of normal daily activities, but limitations are reported for PA-related activities. Participants in this sample reported significant activity limitations that were not directly related to PA. However, limitations in the activity of running are reported as a barrier to PA participation: “It does feel very awkward when I run, which I don't like, I don't like that awkward feeling. I don't feel balanced.” [P1] “[It] feels like it's harder for you to run now physically.” [P6] In addition, one participant reported difficulty executing resistance training exercises during his time in rehabilitation: “I was doing some stuff that was really hurting my leg.” [P5]
Significant participation restrictions are reported in desired PA and leisure activities for these participants. The majority of participants reported differences in their preamputation PA habits compared with their postamputation habits. Three participants reported no longer being able participate in recreational sports: “I used to play softball…but to be honest I was just afraid I would get hurt.” [P2] One participant indicated that he no longer participates in running for exercise and health benefits: “[I used to run] maybe three to four times a week. I am not doing hardly anything cardiovascular other than chores and work now.” [P1] Some participants note difficulty using public facilities for exercise: “Doing some stuff in public is a pain in the butt.” [P3] Others indicate participation restrictions in various leisure activities for fear of injury: “It is not an activity that I will like to do anymore, because I can get hurt again.” [P4].
The majority of participants reported positive outcome expectancies of PA participation for general health benefits. A significant number of the participants express the belief that PA participation would benefit their overall health. These positive outcome expectations of PA serve as a facilitator to participation. More specifically, the use of PA for weight management is identified as a facilitator: “I've probably gained 50-lb postincident and that doesn't make me very happy.” [P1] One participant reported not having enough free time for structured PA, but values its benefits enough to work it into his work day: “I've made a conscious exchange. Instead of working out at the gym, I'm going take care of my health and stuff like this and keep active by stairs, walking briskly, and stuff like that.” [P3] In addition, one participant reported that PA participation gives him more energy throughout the day: “You feel a lot better when you're out doing stuff. I feel like I have more energy.” [P6]
Personal motivation acts as both a barrier and facilitator to PA participation. Some participants reported they feel the need to compete with their able-bodied counterparts (e.g., in work or leisure activities). However, this motivation was reported as being both a barrier and a facilitator to PA participation. One participant reported it as a barrier: “Since it doesn't work as well as a biological leg it makes it hard to keep up with the other people that I'm competing against. I shouldn't be competing with them, but I kind of do turn it into a competition.” [P1] A different participant considers this need to compete against able-bodied counterparts to be a highly motivating facilitator: “I think being an amputee has just kind of driven me to really do the best I can and really be competitive with nonamputees.” [P2] Some participants reported motivation to be as active as possible by serving as an inspiration or role model to other persons with amputation: “I serve in a motivating capacity to newly injured soldiers so that they can see that their injury doesn't have to change how they like to live their lives.” [P2] However, for others, motivation acts as a barrier to participation. One participant reported that due to low cardiovascular endurance his motivation to do anything physical is almost completely diminished: “Everything is so much trouble to do…you is not as motivated to do anything that is physical. It is just a little tougher to do everything.” [P4] Some participants reported wanting to spend time with their families rather than in structured exercise: “I need to do enough to play with my girls and my grandson.” [P3] This same participant also notes that he perceives himself to be in relatively good health: “Why I don't spend time at the gym and stuff like that is that I perceive—and it's all perception—I perceive myself to be in pretty good health.” [P3]
Social opportunities serve as facilitators to PA participation in persons with LLA. Some participants reported their primary PA participation as spending time with their families: “…she (my daughter) knew was that dad was supposed to drive them (my children) to the park so they can play and she was all concerned whether I was going to have my leg amputated, and I had told her, I said, within a year of my having this amputation I'm going take you to the park and we're going play. That made her just brighten up and that gave me a huge drive and desire that about 4 months later after my amputation we actually went to the park and slid down the slide with her, swung on the swing, and ran around the park. I don't even want to think about my life without doing that.” [P3] One participant reported that he enjoys the new relationships that have developed through his PA participation: “It's opened up a whole new world…I've met some of the best people in the world and it's just been really good.” [P2] Other participants reported seeking the opportunity to connect with other persons with amputation during PA: “I think it would be a blast to be able to play sports with other amputees.” [P1] The majority of participants reported seeking the opportunity to serve as advocates: “I rode a bicycle from Oklahoma City to Dallas in 2 days, which is a hundred miles each day, about 2 and a half years after my amputation for an amputee awareness project.” [P3] Another participant indicated a desire to serve as a role model for persons with new amputations through his PA participation: “I'm a big-time educator and I love to see, not even just kids, but adults that feel like their life is over and inspire them to do something positive with themselves or be positive to other people.” [P7]
The quality of postoperative care directly influences PA participation. A number of the participants in the present study reported that their postoperative care experience contributes to their lack of PA participation restrictions. One participant reported that the “family-like” atmosphere of his postoperative care team contributed to his quality of life and PA participation: “I think what has affected positively my quality of life the greatest is that through this process whether it was the bone bridge surgery by Dr Ertl, whether it was Vickie's smile, Dr Dionne's hugs, or Jonathan's patience, I don't know.” [P5] Another participant reported that the rigor and intensity of his postoperative care is what he valued: “I got ready the 9 months while I was in the hospital with their diet and I worked out everyday. I worked out my upper body, my core, and my legs everyday.” [P6]
However, not all participants felt their postoperative care was a benefit to their recovery. For these participants, their postoperative care experience actually serves as a barrier to their PA participation. One participant reported concerns that his rehabilitation professional had no prior experience with the TOA population: “I think it's crucial that the folks that are putting me through the physical therapy understand what's going on with an amputee.” [P5] Further, one participant even reported that his postoperative care team came across disinterested in his progress: “So it's just real frustrating because you feel like nobody wants to help you.” [P8] Another participant reported that he felt his postoperative care team was only concerned with his ability to walk effectively and did not challenge him enough or consider his individual postsurgical goals: “They came in; they put the leg on and told me to call if I had any problems…but actual physical rehabilitation, it didn't happen. You know, it was like you walk just fine, that is all you need.” [P4] Other participants reported that they felt their times in their postoperative care programs were too short in duration and expressed a desire to continue: “I do remember that when they told me I was ready to leave therapy I was depressed. I wanted to keep going to therapy.” [P1]
In the present study, participants reported minimal body structure impairments related to their amputation, but still experience body function impairments. Study participants also reported activity limitations and participation restrictions to their desired PA preferences. While the majority of the participants reported valuing PA benefits, they fail to identify the impact that PA participation could have on their functional capacity. Personal motivation serves as both a barrier and facilitator to PA participation, and the opportunity to socialize during PA is important to these participants. Interestingly, a number of these participants also reported that the perceived quality of their postoperative care has an effect on their current PA habits.
With traditional transtibial amputation, there are several structural impairments commonly reported including HO, soft tissue injuries in the residual limb, and phantom limb pain syndrome.13–15 Mild HO occurs in approximately 62% of LLA patients, being even more severe in traumatic injuries (45% with severe HO).14 Deep tissue injury (DTI) in people with LLA occurs as a result of compressive forces placed on muscle tissue through bone pressing against the prosthetic socket, and the severity is influenced by the bone-muscle interface in the residual limb.15,23 Phantom limb pain occurs in approximately 60% to 80% of amputation patients and, even though the exact etiology is unknown, both peripheral and central nervous systems are believed to play a role.13 The general lack of these structural impairments in study participants is possibly attributable to the osteomyoplastic procedure. Utilizing the creation of a synostosis (i.e., bone bridge) and the reconstruction of the involved musculature to relative anatomic positioning, the osteomyoplastic procedure claims to provide a “stable, dynamic limb that allows for efficient rehabilitation, long-term health, and easier, more functional prosthetic fittings.”21 The present data do not allow for one to either support of refute this statement. However, future research comparing differences in the barriers and facilitators for PA between those with osteomyoplastic and conventional LLA is warranted.
The body function impairments reported by these participants are partially consistent with impairments commonly reported within the population of individuals with amputation.24 People with conventional amputation have decreased aerobic capacity, muscle atrophy in the residual limb, and strength asymmetry between their lower limbs compared with the healthy population.16–18 Study participants reported decreased cardiorespiratory fitness and lower-limb muscular strength as primary barriers to PA participation. Another common problem is related to the integument, commonly presenting as pressure ulcers and calluses due to frequent and improper prosthetic use,19 and presented as a barrier to PA for these study participants. These skin issues are linked to prosthetic fit and function. Currently, research is ongoing to determine what areas of the residual limb are most likely to be affected during different gait tasks to develop strategies for prevention of related skin lesions.25
With similar body function limitations to those found in the literature, it is understandable that these participants reported similar activity limitations and participation restriction. In the present study, 66% (6 of 9) participants reported participation restrictions in PA and leisure activities relatively consistent with the literature base (78%).2 However, only 22% (2 of 9) of participants reported participation restrictions in employment, which is less than what is previously reported (53%).2 The authors hypothesize that the differences between PA and leisure participation versus employment for these participants are due to their lack of limitations in activities of daily living (ADLs). Limitations walking long distances and in day-to-day work tasks could have been expected but are not reported by these participants, thereby allowing them to fully participate in their respective work environments.2 However, the activity limitations reported during running and strengthening exercises by these participants may contribute to the observed PA and leisure participation restrictions.
The benefits of PA in the general population are well documented.9 The majority of participants in the present study reported having positive outcome expectancies of PA participation as a way to improve general health and weight management. However, these participants did not recognize how PA can benefit ambulatory function and reduce potential risk of injury. Muscular strength, balance, and aerobic capacity are associated with improved ambulatory function and the reduction of fall risk in the population of individuals with amputation.26–29 It is reasonable to posit that improvement in these body functions will translate into increased participation in recreational or leisure activities for people with LLA. However, studies investigating the impact of these factors on recreation or leisure activity participation for LLA have yet to be conducted. With the potential to improve body functions as well as body image, the benefits of PA participation beyond mere general health benefits should be better communicated to the population of persons with amputation.30 With this in mind, motivation to participate in PA serves as a barrier and facilitator for people with TOA. With more barriers than facilitators exist to PA participation for people with TOA, increasing motivation to participate in PA is paramount.31 It is possible that by educating people with TOA of the population-specific psychological and physical benefits of PA, one can positively affect their outcome expectancies toward PA participation. After health behavior change theory, positively influencing individuals' outcome expectancies associated with a health behavior change will increase individuals' intention to adopt the desired health behavior.32 Whether such health promotion interventions implemented during postoperative care are effective in encouraging people with LLA to increase PA participation warrants further investigation.
One of the most interesting findings reported is how specific postoperative experiences influenced their PA habits. This finding is intriguing given the fact that participants were not asked any direct questions about their postoperative experiences and such information was voluntarily provided. A few participants expressed the feeling that their postoperative care did not meet their needs, while most reported that it was a significant benefit to them. There were notable differences in postoperative care for the participants that reported it as a perceived benefit versus a barrier. While it is difficult within the present study to postulate reasons for the discrepancies between these two participant perspectives, results do suggest there is inconsistency in the quality and standardization of postoperative care for people with TOA. Guidelines for rehabilitation of persons with TOA have recently been updated in attempt to standardize care for this population.33,34 Rehabilitation professionals should reference these guidelines and recommendations to facilitate recovery time, maximize function, and reduce participation restrictions for the TOA population. Further, According to Thompson and Kramer,35(p63) the concept of a multidisciplinary approach to postamputation rehabilitation has a strong historic foundation, “…in 1948, a protocol was established that provided the basis for the amputee clinic team. At that time, the clinic team comprised a physician, prosthetist, and therapist. Gradually, as attention focused on the entire patient and not just on the residual limb, more personnel were added to the clinic team.” Yet today in the United States, postamputation rehabilitation has become inefficient, “siloed,” compartmentalized, and sequential. According to anecdotal reports by patients who come to our amputation clinic for possible revision surgery, many surgeons follow their patients until the sutures are removed from the residuum 2 to 3 weeks after surgery and then release them from direct care. The coordination of the rehabilitation and prosthetic care is typically inconsistent and left up to the patient or the payer to unsatisfactorily resolve. This disjointed course of treatment reduces the timeliness and effectiveness of the patient's rehabilitation and negatively impacts the ultimate outcome. Future research should investigate patient outcomes between integrated models of postamputation care and more conventional practice settings.
In 2008, Privratsky36 found at least 91% of the prosthetists surveyed agreed that patient outcomes were improved through physical therapy (rehabilitation) after the provision of the prosthesis. Castillo et al.37 reported that 23% to 48% of patients at their first follow-up visit had a need for therapy but were not receiving any, and at a 2-year follow-up, that percentage rose to 68%. Interestingly, the author referenced no insurance, pain, low levels of education, fitness levels at time of injury, smoking, and having severe muscle injury as barriers to physical therapy. Our results indicated that levels of pain, fitness, and soft tissue injury to the residuum as barriers to PA. Surgeons, therapists, and prosthetists fundamentally agree that it takes everyone to maximize the outcome for the patient. However, there is little evidence to show that agreement has translated into actual effective teams that provide cooperative care. Not all of the medical professionals involved are reinforcing the long-term need and value of continued PA for general wellness in patients after amputation. It is critical that the health care team emphasize the importance of rehabilitation and a long-term PA or wellness plan to promote overall health and long-term success through prosthetic use after amputation.
One strength of the study is the richness of the data collected from each participant. Further, this is the first study to qualitatively examine barriers and facilitators to PA participation in persons with TOA. The credibility of the research team and its experience with the TOA population enhanced the trustworthiness of these data. However, the present study is not without its limitations. The small sample size, males-only sample, and homogenous cause (i.e., trauma) and level (i.e., transtibial) of amputation for these participants make generalization to the entire TOA population difficult. In addition, although all practical steps were taken to minimize bias, there is always a risk that having prior experience with the TOA population can inadvertently affect the bias of the research team.
Future research should focus on investigating the role that postoperative care has on PA participation for people with TOA. Additional studies need to test the modifiable factors of the ICF categories identified in this study for increasing PA participation in the TOA population. For example, further research should investigate whether educating TOA patients on the benefits of PA for improving overall function will result in increased PA participation after discharge from rehabilitation care. Additional studies should seek to identify any potential differences in the barriers and facilitators to PA participation between level of amputation, amputation procedure, and cause of amputation.
People with TOA, even those without additional comorbidity or major structural impairments, continue to experience body function impairments, activity limitations, and participation restrictions associated with PA, consistent with findings for people with conventional transtibial amputation. The postoperative care team can play a significant role in the adoption of a physically active lifestyle for people with TOA through both effective patient education and the implementation of comprehensive, patient-centered rehabilitation programs.
The authors would like to acknowledge the research assistants of the Mechanical Therapy Research Laboratory at the University of Oklahoma Health Sciences Center (OUHSC) for their assistance during recruitment and transcription of the data.
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