Understanding the User Experience of Lumbar-Support-Assistive Devices in Lower-Back Pain Patients: Design Recommendations

Abstract

A positive user experience is crucial for enhancing user adherence throughout the utilization of lumbar-support-assistive devices (LSAD). However, there is a lack of research for optimal user experience with LSAD in the existing literature. Therefore, this study aims to explore how patients with lower-back pain use LSAD and assess their satisfaction and overall experience. Based on this, we aim to provide design improvement recommendations for LSAD to researchers in the relevant field. Through in-depth interviews with 14 LSAD users, key themes were identified using reflexive thematic analysis. The results indicate that participants were “somewhat satisfied” with the overall experience with their LSAD. The key factors influencing the LSAD-wearing experience were: (1) key design challenges in improving LSAD (stability, fit and, comfort), (2) providing necessary assistance (potential barriers and prompts), and (3) individualizing needs and balance of design (aesthetics, dimensions, safety, and cleanliness). All participants reported that poor stability, fit, and comfort of LSAD were the main reasons for an adverse experience. It is worth noting that users may encounter potential barriers when initially using LSAD. Furthermore, younger participants perceived pressure related to appearance and expressed concerns about the exposure of their health privacy during social interactions involving the LSAD. Based on these findings, we have proposed a set of comprehensive LSAD design-improvement recommendations, which serve as a foundational reference for future improvements.

1. Introduction

Lower-back pain is a common ailment, affecting approximately 70–85% of the global population [1]. The high medical expenses associated with lower-back pain have significant impacts on both society and patients [1]. Lower-back pain has been identified as a leading cause of disability [2], prompting urgent actions within the medical community [3,4,5]. In addition to conventional rehabilitation options, lumbar-support-assistive devices (LSAD) have been used as adjuncts to rehabilitation, given the high recurrence and prevalence of lower-back pain [6,7].

LSAD is a type of rehabilitation-assistive device widely utilized in the medical field. They are primarily a device designed to provide additional support to the lumbar region, and such devices are also called “back support belts”, “lumbar support belts”, “weightlifting belts”, or “abdominal belts” [8]. While the forms of LSAD are diverse, they can be primarily categorized into three design types: flexible, semi-rigid, and rigid [9]. Figure 1 shows examples of their popular products. In general, rigid braces are widely employed for patients experiencing moderate to severe lower-back pain, while semi-rigid and flexible braces are primarily used to alleviate mild to moderate pain [9]. Although passive/active exoskeletons can also be considered as a special form of LSAD, such devices are not widely understood by users in real-life situations. Currently, researchers are still exploring user attitudes toward the acceptance [10,11,12] and perceptions of use [13] of such devices. Therefore, this study will not consider this type of device as an anticipated research focus within the LSAD category.

LSAD-Related Work

In the treatment of back pain, there is now a greater emphasis on self-management, physical and psychological therapies, and certain forms of complementary medicine, with less emphasis on medication and surgical treatments [15]. For example, an American guideline on the assessment and treatment of back pain indicates a reduced reliance on pharmacological treatments, and recommends non-pharmacological therapies as the preferred treatment option [16]. Among these, LSAD is often used as an adjunctive approach by patients with back pain. In most studies, LSAD is considered to improve the pain condition of patients with back pain. Some studies have clearly elucidated the benefits and functions of these types of assistive devices:

• Limit overall trunk range of motion [17,18];
• Ameliorate disc stress by increasing abdominal pressure [19,20];
• Enhance proprioception and stability, improving posture through applied pressure [21,22];
• Have no negative impact on muscle strength or lumbar spine function [23,24];
• Reduce lumbar muscle fatigue [25];
• Enhance torso mobility for daily activities [26,27].

In summary, LSAD is designed to provide additional lumbar support and facilitate lumbar rehabilitation. Prior studies have predominantly examined the efficacy [27,28,29] and operational mechanisms [23,24,30] of LSAD, leaving patient-experience aspects relatively unexplored. However, a positive attitude (i.e., the benefits brought by the device) has become a decisive factor in patients’ use of such devices and is considered to some extent to offset users’ adverse experiences [31]. Nevertheless, it is essential to consider that these adverse experiences may not be entirely offset. Instead, they may represent a compromise that users reluctantly accept to achieve favorable rehabilitation outcomes. Therefore, understanding users’ experiences in product design (in this study, LSAD) and involving users in the process are considered crucial [32,33,34]. This includes understanding and comprehending users’ physiological, psychological, and environmental factors, needs, and priorities [35,36]. This is beneficial for reducing barriers to the use of assistive devices [37] and improving compliance during the rehabilitation process.

A recent study based on a survey of preferences and satisfaction among 258 elderly individuals found that users prefer integrated products, minimalist designs, and LSAD that provide sufficient support [38]. Another study surveyed 40 patients with lumbar disc herniation, revealing that the period of their usage of LSAD did not exceed one year [39]. Dissatisfaction primarily stemmed from fabric, mobility, and design, with discomfort being the most common complaint [39]. Park and Kim’s study [40] indicated that size is a factor leading to a worse wearing experience for obese users with commercially available LSAD. The existing literature provides valuable supplementary information for research related to the user experience of LSAD, although there is still a certain degree of ambiguity regarding the usage and patient-wearing experience of these devices, and we have not yet fully understood the actual usage scenarios of these devices or patient satisfaction. Understanding how patients use LSAD and their satisfaction are crucial for improving LSAD [41]. Patient satisfaction not only relates to their adherence to rehabilitation plans but can also influence the effectiveness of rehabilitation.

Given the widespread use of LSAD in lower-back pain management, there is a relatively limited amount of research on the user experience of LSAD. Therefore, more research on the wearing experience of LSAD is still needed to provide relevant researchers with more detailed information during the patient rehabilitation phase. This study aims to gain a comprehensive understanding of how patients with lower-back pain use LSAD, patient satisfaction, and the overall wearing experience. The objective is to provide LSAD design improvement recommendations for researchers and developers, thereby enhancing adherence during the usage process for lower-back pain patients. We strive to provide information for professionals in the rehabilitation field, engineers, and designers of LSAD technology. Specifically, we have four goals:

(1)

Describe the types of LSAD used by lower-back pain patients;

(2)

Exploring how lower-back pain patients use LSAD;

(3)

Evaluate lower-back pain patients’ satisfaction with LSAD;

(4)

Generate design improvement recommendations.

2. Methods

2.1. Theoretical Framework

In formulating the questionnaire and framing interview questions, this study referred to Fuhrer et al.’s [42] Conceptual Model of Assistive Device Outcomes. The model emphasizes that outcomes arise from the interactions among the device, user, and environment. By analyzing these factors, we can gain a more comprehensive understanding of the outcomes of assistive devices, including potential positive and negative impacts. Therefore, in this study, this model guided the development of our data collection tools and data analysis. Furthermore, during the interview process, Heiselberg and Stępińska’s [43] qualitative interview technique provided crucial technical guidance. This technique assisted us in collecting rich and thick data in the early stages, obtaining information that might be challenging to acquire otherwise.

2.2. Study Design

We employed qualitative methods to gain insights into the diverse rehabilitation experiences of lower-back pain patients using LSAD. This study adheres to sound scientific principles and ethical guidelines, and it was granted an exemption from ethical review by the Changzhou Institute of Technology. The decision is based on the following facts: the conducted research does not involve any experimental or invasive procedures, and participants will not face any potential harm or discomfort during the participation process. Additionally, in accordance with the announcement by the Chinese National Health Commission on 18 February 2023, this research project is considered exempt under the category specified in the Notice on the Issuance of Ethical Review Procedures for Life Sciences and Medical Research Involving Human Subjects. Between 12 May 2024 and 17 May 2024, we conducted online interviews with 14 participants. Before the interviews commenced, electronic copies of the informed consent (Chinese) form were obtained from participants, clearly stating their right to withdraw from the interview at any time. At the beginning of the interviews, the purpose of the study and ethical considerations were reiterated in person.

2.3. Data Collection Tool

The research team formulated a semi-structured survey questionnaire based on Fuhrer et al.’s [42] conceptual model. The questionnaire consisted of four sections, comprising both closed and open-ended questions. In addition, the validity of the questionnaire was assessed in two steps. First, feedback was obtained from two experts in the field of rehabilitation—a professor in rehabilitation medicine and a professional working in the assistive devices domain. Secondly, a pilot test was conducted with three participants to ensure that the questions were clear and could gather information relevant to the research objectives. Finally, based on expert feedback and suggestions from pilot participants, some revisions were made to the original survey questionnaire.

In the first section of the questionnaire, the research team formulated questions related to demographic information. Participants provided their age, gender, occupation, type of lower-back pain, and history of LSAD usage in interviews.

In the second section of the questionnaire, participants underwent interviews regarding their LSAD usage. Specifically, researchers asked four questions related to LSAD usage:

• What type of LSAD have you used? Could you show or describe it to us?
• At which stage of lower-back pain do you typically use LSAD? For example: before regular treatment, after regular treatment, relying only on the LSAD for rehabilitation, etc.?
• In what environment or scenario do you usually wear LSAD?
• How often did you use LSAD on average during your most recent episode of lower-back pain?

The third section of the questionnaire incorporated, in interview format, device satisfaction questions related to the Quebec User Evaluation of Satisfaction with Assistive Technology 2.0 (QUEST 2.0). Participants responded to eight questions, evaluating their satisfaction with various aspects of the device on a 5-point Likert scale (1 = completely dissatisfied, 5 = very satisfied). According to the QUEST 2.0 reference manual, participants were required to provide detailed explanations when any item scored below 5 [44]. QUEST 2.0 also includes four items related to services but, during the pilot test, three participants found them confusing as they had never received any service related to LSAD. Therefore, in the formal testing, we did not administer the service test section of QUEST 2.0 to the remaining participants.

At the end of the questionnaire, we presented participants with open-ended questions to further explore detailed information about their experiences wearing LSAD. We specifically inquired of participants (1) if they had any additional perspectives or sentiments regarding the experience of wearing LSAD and (2) if they had any corresponding suggestions or requests.

2.4. Participants and Data Collection Process

We attempted to recruit lower-back pain patients who had used or were currently using LSAD, utilizing social platforms such as Little Red Book and lower-back pain discussion groups on WeChat for recruitment. This study had five inclusion criteria. Participants were required to: (1) be at least 18 years old, (2) have no surgical plans, (3) have engaged in LSAD usage within the past six months, (4) be capable of self-care, and (5) have used a flexible or rigid LSAD.

When conducting qualitative research, to ensure data saturation, recruiting 6–12 participants is generally considered sufficient to meet the research requirements [45]. Therefore, by utilizing social platforms and participant referrals, a total of 14 eligible participants were recruited to engage in meetings with the research team. The data for this study were collected through Tencent Meeting and WeChat platforms, using both audio and video formats for interviews. Interview durations varied between 22 and 54 min.

2.5. Data Analysis

All interactions between participants and researchers were transcribed into text format using the transcription feature of the Redmi K40 smartphone. The researchers verified this manually to confirm the accuracy of the transcription. Descriptive statistics were primarily employed to identify the types of LSAD used, specific situation of usage, and device satisfaction among participants. To gain further insights into the satisfaction and experiences of LSAD participants, we used the (reflexive) thematic analysis approach proposed by Braun and Clarke [46], and conducted inductive coding [47] during the initial stages of data analysis. Inductive coding is a bottom-up approach that allows researchers to develop themes from raw data [47].

We repeatedly read the transcribed text to familiarize ourselves with the data, and selected meaningful keywords and citations to assign codes to. Under the guidance of the research objectives, potential themes were identified. The research team questioned, scrutinized, defined, and named the potential themes and codes during the seminar, guided by the research objectives and the twenty key considerations proposed by Braun and Clarke [46] for reflection. After multiple rounds of reflection and discussion, the research team ultimately finalized the themes based on potential themes. Following the thematic analysis, the team cross-checked reflective records from others to ensure that the final themes accurately reflected participants’ genuine experiences.

3. Results

3.1. Demographics

Fourteen people participated in the study. The average age of participants was middle-aged (M = 41.43 years; SD = 12.04), with 57% females (n = 8) and 43% males (n = 6). Participants were primarily categorized by three types of lower-back pain: lumbar muscle strain (n = 6, 43%), lumbar disc herniation (n = 7, 50%), and sprain (n = 1, 7%). Finally, participants had a history of LSAD usage ranging from 1 to 36 months.

Table 1. Detailed demographic information of participants.

Participants	Gender	Age	Occupation	Type of LBP	History of LSAD Usage
1	Male	53	University Professor	Lumbar muscle strain	6 months
2	Female	52	Administrative Staff	Lumbar disc herniation	3 months
3	Female	44	Aerobics instructor	Lumbar disc herniation	8 months
4	Female	25	Salesperson	Lumbar disc herniation	12 months
5	Male	46	Physical education teacher	Lumbar muscle strain	2 months
6	Male	25	Student	Lumbar disc herniation	3 months
7	Female	55	Aerobics instructor	Lumbar disc herniation	24 months
8	Female	59	Swimming instructor	Lumbar muscle strain	8 months
9	Male	43	Basketball coach	Lumbar disc herniation	12 months
10	Male	40	Electrician	Sprain	1 months
11	Female	51	Clerical staff	Lumbar muscle strain	36 months
12	Male	32	Safety officer	Lumbar muscle strain	14 months
13	Female	29	Student	Lumbar muscle strain	5 months
14	Female	26	Student	Lumbar disc herniation	1 months

displays detailed demographic information of the participants.

3.2. Participants’ Usage and Types of Usage

In response to inquiries about LSAD usage types, six participants (43%) indicated frequent use of flexible lumbar belts, while eight participants (57%) reported frequent use of semi-rigid lumbar belts. When asked at what stage LSAD were typically used, the most common response was “Solely reliant on LSAD” (n = 10, 72%), followed by “Before and after regular treatment” (n = 3, 21%) then “After regular treatment” (n = 1, 7%). When asked about the typical scenarios in which participants usually use LSAD, the most common response was “Daily life” (n = 6, 43%), followed by four participants (29%) mentioning “While sitting at work”, three participants (21%) indicating “While standing at work”, and one participant (7%) specifying “During exercise”. The results indicate that the majority of participants wear LSAD for an average of 6–8 h per day when experiencing lower-back pain. Figure 2 and

Table 2. Usage and types of LSAD (further explanation of Figure 2).

	Type of Use	Typically Used at Which Stage	The Environment or Situation in Which the LSAD Is Worn	Average Frequency of Use per Day
Red	Flexible LSAD	After regular treatment	In sitting position	1–3 h
Blue	Semi-rigid LSAD	Before and after regular treatment	In standing position	3–6 h
Purple	-	Solely reliant on LSAD	When exercising	6–8 h
Greener	-	-	In daily life	More than 8 h

provides detailed information about the usage and types of LSAD among the participants.

3.3. User Satisfaction

According to the explanation in the QUEST 2.0 manual, overall satisfaction with LSAD among all participants was “somewhat satisfied” (M = 4.12, SD = 0.48). Among them, the average satisfaction score for flexible LSAD was 4.21 (SD = 0.57), while the average score for semi-rigid LSAD was 4.06 (SD = 0.46). In the eight device satisfaction items, all participants were least satisfied with comfort (M = 3.36, SD = 0.72). Overall, there were no significant differences observed among different types of LSAD, as indicated in Figure 3.

4. Qualitative Findings and Discussion

The qualitative data analysis combines participants’ explanations of their dissatisfaction in the QUEST 2.0 and responses to open-ended questions to form common themes. Through a reflective thematic analysis, we identified three perspectives and feelings related to the experience of wearing LSAD as expressed by participants: (1) key design challenges in improving LSAD, (2) providing necessary assistance, and (3) individualizing needs and balance of design (See Figure 4).

4.1. Key Design Challenges in Improving LSAD

This overarching theme comprises three subthemes: (1) Stability, (2) Fit, and (3) Comfort.

4.1.1. Stability

All semi-rigid LSAD-using participants and some flexible LSAD-using participants reported varying degrees of slippage issues with LSAD during the activity. When slippage occurs, participants need to manually readjust the device by pulling it down. The shared expectation among all participants is that LSAD should demonstrate good stability to minimize the negative emotions associated with frequent adjustments during activities. For instance, Participant 7 mentioned: “I think everyone who has worn it has experienced having to adjust it to the right position from time to time during activities […], I think everyone should feel quite helpless”. Participants emphasized that improving device stability could potentially increase the utilization rate of LSAD during activities. In addition, for participants engaged in outdoor work, stability indirectly influenced the device’s support effectiveness and their trust in the device.

“What I mean is, it would be great if it could be integrated with the pants because I need to lift my arms, squat […], some larger range of motion. Wearing it while working is greatly affected, but I still need it. Can you understand? It always slips.”

(Participant 3)

“When I’m delivering or picking up goods, it slides with my clothes. Every time I finish, I must pull it down with my hands. It really affects my work a lot.”

(Participant 4)

4.1.2. Fit

The majority of semi-rigid participants reported ergonomic issues with the LSAD not fitting well to the lumbar region. The unanimous consensus among participants was that the lack of conformity of the LSAD to the waist constitutes a direct cause for abandonment. As reported by Participant 5, “discontinuation occurred after wearing for a period, primarily due to the perception that the steel plate at the back did not conform to the body’s curves, resulting in a sensation of emptiness around the waist”. The primary cause of non-conformity arises from subtle discrepancies between the rear steel bars and the individual’s body contours. Some participants recommended personalized customization for individuals with unique body shapes: “Perhaps due to my body type, it’s currently challenging to find an LSAD that conforms to the curvature of my waist. I can only make do with those ‘soft plastic bars’ for now” (Participant 11). Furthermore, some participants indicated that the poor fit had led to frequent slippage of the LSAD during activities, thereby compromising its intended functionality.

“Because the waist has a curvature, most of the waist belts I used before did not conform to the curvature of the waist, leading to frequent slipping issues.”

(Participant 4)

4.1.3. Comfort

The shared perspective among participants was that the majority of LSAD currently available are excessively heavy, contributing to issues such as poor breathability. This issue primarily arises during the summer, with some participants experiencing varying degrees of skin problems due to moisture and heat accumulation around the waist: “I don’t think I can use it at all in the summer because its heat dissipation is so poor, […] it’s very thick, like wrapping a wet towel around, I feel like my waist is about to rot” (Participant 7). In addition, female participants highlighted the significance of the edge material and craftsmanship of LSAD, particularly during the menstrual period: “You may not know, but some LSAD have either rough or hard edges, and that spot under the breasts is uncomfortable to be pushed up against, especially during a girl’s menstruation […] I hope that the design will be more considerate and not bring extra discomfort to women” (Participant 14).

The in-depth investigation into LSAD user experience has afforded us an opportunity to delve into the personal perspectives of individuals suffering from lower-back pain, enabling us to explore novel insights beyond anticipated or previously known factors. This overarching theme reinforces participants’ desire to achieve favorable rehabilitation outcomes through the improvement of LSAD design. However, negative experiences during the wearing process have, to some extent, impacted the perceived efficacy of LSAD, thereby diminishing participants’ confidence in sustained usage. Participants typically associate stability and fit with the effectiveness of LSAD. Therefore, enhancing stability and fit may potentially increase compliance in patients with lower-back pain during usage. This can be achieved through design measures. For stability, we recommend a particular focus on the relationship between LSAD and the lower body/pants. Regarding fit, patients should be allowed to make minor adjustments to the hard plastic for a better fit.

Additionally, according to the results of QUEST 2.0, comfort stands out as the most prominent issue. Therefore, in the design process, attention should be paid to the selection of materials. This may involve the use of soft and breathable materials, as well as materials with anti-microbial and odor-resistant properties, to ensure that patients with lower-back pain feel comfortable while wearing LSAD [38], thereby increasing both their willingness to use it and its effectiveness. In the design of LSAD edges, gender differences should be taken into full consideration to minimize inconvenience for female patients.

However, unexpectedly, almost all participants reported the presence of the three key experiential issues with their LSAD. Nevertheless, a majority of participants expressed their intention to continue using it, and we attribute this phenomenon to users deriving optimal benefits from it [31].

4.2. Providing Necessary Assistance

This overarching theme consists of two subthemes: (1) potential barriers and (2) prompts.

4.2.1. Potential Barriers

Participants’ main potential barrier lay in not being sure whether they were wearing it effectively. One crucial aspect is the lack of clear usage guidelines, especially during initial use.

“I understand that it benefits our waist. But, when I first started wearing it, I didn’t know how tight it should be—it was all based-on feeling. […] The doctor told me to buy the one with strong support, LSAD. […] But how tight should I wear it for it to be effective? It would be helpful to have instructions on how to wear it or markings and information provided.”

(Participant 3)

The common perspective among participants is that LSAD should include a credible scientific basis for tension data. Participants believed that providing scientifically reliable tension data can reduce their concerns and barriers during usage, emphasizing the need to translate such data into specific usage guidelines for LSAD. For example, they felt there should be guidance on the appropriate level of tension for different types of lower-back pain to better assist them in understanding the effectiveness of LSAD.

“After putting this on, my back feels too swollen […], but we are not sure about the intensity. What level of tension is more appropriate? Is tighter always better? We don’t know. We can’t rely on comfort for judgment. Sometimes, it’s uncomfortable when it’s too tight, but it helps your back recover quickly. Sometimes, it’s comfortable, but it might be an ineffective wear. So, we need assistance in this regard.”

(Participant 5)

“To be honest, this thing is either too tight, making my waist uncomfortably swollen, or too loose, rendering it ineffective. And, I’ve heard people say that wearing it too tightly is actually bad for the waist. I can only rely on my feelings to adjust it. […] But then again, if someone tells me that wearing it tightly is the most effective for my waist, I’ll endure the discomfort for the sake of my waist.”

(Participant 2)

4.2.2. Prompts

Some participants indicated that posture reminders are necessary for individuals who experience back pain due to prolonged sitting at work. For instance, participants suggested incorporating proactive features such as vibrations or audible alerts to monitor sitting posture.

“It would be much better to have such a reminder because poor sitting posture can aggravate lumbar muscle fatigue. Anyway, it’s good to have such a reminder in the end.”

(Participant 11)

Some participants expressed expectations of smart technology, hoping that LSAD could provide precise health feedback through sensors, data analysis, and other means: “If it could monitor my sitting posture in real-time and even offer some simple exercise suggestions, that would be perfect. I believe such features can help me in my recovery process” (Participant 1). Additionally, participants also reported that scheduled activity reminders would be more beneficial for their recovery. Participant 6 mentioned, “Vibrations or audible alerts can, to some extent, compel us to engage in simple activities, promoting blood circulation and muscle movement in the lower back”.

In this study, participants underscored uncertainty regarding the effective wearing of LSAD as a motivating factor necessitating assistance. Participants expressed a desire for guidance based on scientific principles to help them ascertain the effectiveness of wearing LSAD. Indeed, in a similar study, an investigation was conducted on the impact of the tightness of abdominal belts on the maximum acceptable weightlifting, and it was determined that the effectiveness of abdominal belts depends on their tightness as well as on task variables [48]. This highlights the critical role of tightness in the effective wearing of LSAD. In addition, providing appropriate cues based on the needs of different scenarios may be more helpful to the rehabilitation outcomes of patients with lower-back pain. Accordingly, when designing LSAD for individuals with lower-back pain, the incorporation of smart technology or wearable materials should be considered. This, combined with factors such as the patient’s activity level and the severity of lower-back pain, can offer personalized exercise services for patients [49,50].

4.3. Individualizing Needs and Balance of Design

This overarching theme consists of four subthemes: (1) aesthetics, (2) dimensions, (3) safety, and (4) cleanliness.

4.3.1. Aesthetics

The perception of LSAD aesthetics among participants was polarized, with some individuals believing it had no impact, while others contending that it affected their outdoor activities. Some young participants expressed the view that, after wearing it, they were unwilling to engage in, or intentionally avoided, socializing and activities outdoors. This is mainly because they believed it impacted their image and caused awkwardness due to the “attention received”.

“I can’t stand it when people always stare at me when I’m walking down the street. That feeling makes me very uncomfortable. […] Now, I’ll put it on for you to see. […] It really affects one’s image, doesn’t it? That’s why I always tuck it inside my clothes every time.”

(Participant 4)

Another young participant further supported this viewpoint, stating that if these LSAD could be designed in a stylish or trendy manner, in line with fashion trends, they might not feel pressured when going out.

“In my opining, this kind of thing is mainly used by the elderly and the sick. It’s indeed awkward for young people when they go out. […] I feel like people look at me with the impression of ‘so young and already with back problems’. The most embarrassing thing was when someone offered me a seat on the bus, making me feel particularly awkward. […] Have you seen the Teenage Mutant Ninja Turtles? It’s a similar feeling, not wanting others to instantly think you’re a patient.”

(Participant 13)

In contrast, the majority of older participants expressed the view that they did not become the “center of attention” when out in public. They were more concerned with the practicality of LSAD, and aesthetics are optional for them.

“I’m almost halfway into the coffin […] The most important thing is that it’s effective; I don’t really care much about how others see it. Sometimes we may be too concerned about other people’s opinions, but everyone has their own problems. Who can truly be perfect?”

(Participant 8)

4.3.2. Dimensions

Some participants reported issues with the size of LSAD, such as difficulties in finding suitable sizes. This results in either excessive or insufficient support.

“Size span is a little big. Each size differs by 10 cm. I initially bought XL, but it was too big, so I exchanged it for L, which turned out to be a bit small. I didn’t want to go through the hassle of exchanging again, so I’m just using it reluctantly.”

(Participant 14)

“The belt size is supposed to be an average size, but you can see that sizes vary among different brands. I tried my best to tighten it a bit more, but still couldn’t achieve it.”

(Participant 12)

4.3.3. Safety

Some participants had security concerns regarding the additional features of LSAD. Participant 7 expressed a particular fear of the device short-circuiting after cleaning: “Especially during the summer, it needs frequent cleaning, but I worry about its waterproof performance.”. Additionally, some participants had concerns about the voltage devices inside LSAD.

“The functionality of salt therapy is essentially a layer of salt with a 220 V voltage temperature control. Because I work in the safety field, I am really concerned about placing a 220 V voltage device around the waist. The consequences would be extremely serious in case of any mishap.”

(Participant 12)

4.3.4. Cleanliness

Participants reported issues regarding the cleaning process of LSAD. Some participants using semi-rigid LSAD reported that the cleaning time is excessively long, and it is challenging to thoroughly clean them: “In principle, you’re not supposed to wash it, but over time it inevitably gets dirty. So, you must dampen it and clean it slowly, which takes a very long time. That’s why my partner helps me every time” (Participant 3). However, for participants using flexible LSAD, the cleaning process remains a highly inconvenient issue: “You can’t put it in the washing machine. I ruined several by doing that before, so I must wash it by hand very gently” (Participant 7).

In addition to the challenges of lengthy and incomplete cleaning, some participants also mentioned other difficulties related to LSAD cleaning. One issue is that the cleaning process may result in wear and damage to the equipment. Participant 6 expressed this concern: “I worry that I might damage it during cleaning. After all, this equipment is not cheap, and I don’t want to shorten its lifespan just because of cleaning.” Additionally, some participants also mentioned that the cleaning process could be an extra burden for individuals living independently.

“No one can help me clean this device, so it is a task which I do alone. It adds to the strain on my lower back. Sometimes, I worry that the cleaning isn’t thorough enough, which affects my mood.”

(Participant 13)

The final overarching theme for lower-back pain patients regarding LSAD experiences is the individualizing needs and balance of design. This theme conveys the perspectives of LSAD users on aesthetic design and other issues related to LSAD. The research findings indicate that young lower-back pain patients place significant emphasis on the negative perceived stress brought about by LSAD, and this stress to some extent affects their normal social interactions and activities. In terms of aesthetic design, some LSAD studies focusing on user preferences have suggested that the inner wear-shape design (a design form that can be worn under clothing) [39] and neutral colors [38] are currently the most favored designs among users. Therefore, for the personalized needs of lower-back pain patients, subsequent improvements or developments of LSAD should focus on reducing the perceived stress among young patients and incorporating some fashionable elements to garner support from the younger demographic.

In addition, cleaning LSAD has become a common challenge for all participants. This is mainly because most LSAD in the current market do not support disassembly, a point supported by our interview data. For future improvements, we recommend adopting a modular design concept that supports the separation of the inner lining and the support framework. This would not only facilitate thorough cleaning of sweat and bacteria from the inner lining but also mitigate the risks to the lower-back during the manual cleaning process.

Finally, based on the results of QUEST 2.0, the satisfaction levels for LSAD dimensions (M = 3.79, SD = 0.86) and safety (M = 3.86, SD = 0.74) were not very high. Combining these findings, we recommend establishing a set of standard sizes for LSAD based on authoritative local anthropometric data. Regarding LSAD safety, manufacturers should consider avoiding the inclusion of voltage devices within LSAD.

4.4. LSAD Design Improvement Recommendations

After a prolonged period of development, LSAD have been crafted into diverse forms and garnered a broad user base. However, given the limited research on user experience for such devices currently, we supplemented this by understanding user usage and satisfaction. Finally, through (reflexive) thematic analysis, we identified directions and factors for improving the LSAD user experience, consolidating them into a guide for design improvement. We further provided recommendations for improving the LSAD user experience in

Table 3. LSAD design improvement recommendations.

LSAD Design Improvement Recommendations
Stability (Golden Guide 1)
When addressing the issue of device slippage, ensure that it does not affect the user’s normal attire; This includes the use of anti-slip materials, while also paying attention to breathability. For example, testing the anti-slip performance of devices by incorporating a mesh structure made from anti-slip materials; Emphasis should be placed on the relationship between the device and pants/lower body, improving slippage issues through clever design techniques (see Figure 5); Consider the user’s usage scenarios. For example: whether it involves frequent bending or squatting.
Fit (Golden Guide 2)
Customized services should be provided based on specific body types; Apply a modular design concept, allowing users to replace the steel plate/rod on the back; Adopt an adjustable design, allowing users to fine-tune the device or the angle of the back steel rod/plate according to individual needs (see Figure 6).
Comfort (Golden Guide 3)
Avoid the use of overly sealed materials to allow for air circulation; Utilize lightweight, high-strength materials to reduce the overall weight of the equipment.
Potential barrier
Provide scientifically credible tension data, detailing the level of tension required for varying degrees of lower-back pain and activity, and visualize it intuitively on the device through data visualization methods (see Figure 7).
Prompts
Consider incorporating smart technology or wearable materials based on users’ rehabilitation needs, providing assistance with correct posture, timed exercises, and health monitoring; Tailor personalized exercise prescriptions based on individual circumstances, including questions to assess the user’s current condition and adjust the workout plan accordingly.
Aesthetic design
Incorporate locally relevant fashion elements into the device based on the cultural and social situations of different regions; Minimize negative perceived stress on users caused by the device, for example, addressing perceptions such as “looking like a patient” or being “too ostentatious”.
Dimensions
Establish a standard sizing scale based on authoritative anthropometric data to reduce the error rate in online purchases for users.
Safety
Consider abolishing the installation of voltage devices in LSAD; Consideration should be given to safer heating aids, such as graphene heating technology or herbs such as Artemisia Argy.
Cleanliness
Based on the modular design concept, separate the inner lining from the support framework to enhance cleaning convenience.

, offering methods and strategies for subsequent improvements and developments. Among the nine guidelines, three hold special significance as participants frequently mentioned them during the interview process, directly or indirectly influencing participants’ confidence in continued usage. Therefore, we designated these three factors (Stability, Fit, and Comfort) as the golden reference guidelines.

Addressing the stability of LSAD can be approached from both material and design perspectives. From a material standpoint, attention should be given to the breathability of anti-slip materials. From a design perspective, a focus should be placed on the relationship between LSAD and the lower body. We have provided a feasible conceptual reference solution from a design perspective for future improvements, as illustrated in Figure 5. We believe that the issue of LSAD sliding can be addressed using a principle similar to that of overalls.

For the fit, we propose an adjustable design to assist users in fine-tuning the steel plate on the back. As shown in Figure 6, the steel plate can be divided into 2–3 segments, and the connecting parts support users in fine-tuning it to conform to the curvature of the waist.

Regarding potential barriers during users’ initial use, we recommend incorporating effective scientific tension values into LSAD through visual design for intuitive representation, as illustrated in Figure 7.

4.5. Theoretical and Practical Implications

The uniqueness of this study lies in its focus on the user experience of LSAD, aiming to provide universal design improvement guidelines for this specific domain. Firstly, through reflexive thematic analysis and patient-centered design [51], we identified potential usage barriers and perceived pressure of LSAD, a factor overlooked in other relevant studies, thereby further addressing a gap in the literature. The research findings indicated that users of LSAD require scientific guidance to help address uncertainties or errors during the wearing process. These insights provide valuable knowledge for follow-up studies and help provide research directions for researchers from other disciplinary backgrounds. Furthermore, they also provide a solid theoretical foundation for subsequent related research.

Most importantly, we proposed a set of universal recommendations for LSAD design improvements. These hold potential practical implications for LSAD manufacturers, healthcare professionals, designers, and individuals suffering from lower-back pain. They contribute to enhancing the quality and applicability of such assistive devices, thereby improving rehabilitation outcomes for individuals with lower-back pain.

4.6. Limitations and Future Research

Firstly, among the five researchers, three focused on user experience research in the field of health design. During the qualitative data analysis, we have to acknowledge that three researchers were influenced by personal beliefs, and preconceived notions and positions, which thereby impacted their assumptions and biases regarding the attitudes of LSAD users to some extent. Their perspectives suggest that, even if LSAD are effective, negative wearing experiences for LSAD users may lead to abandonment, resulting in resource wastage and user frustration and dissatisfaction. The reason for these biases is that they were influenced by individuals in their surroundings who had previously used LSAD, and their evaluations were not favorable. We recognize that this perspective may have a certain bias. Therefore, throughout the entire research process, we introduced inductive coding in the initial stages of the reflexive thematic analysis to reduce the potential impact of this limitation on the research conclusions.

Secondly, another limitation of this study is that the universal design improvement recommendations for LSAD that we ultimately proposed may be most applicable to the flexible and semi-rigid types. The applicability to rigid LSAD remains to be observed. This is mainly due to financial constraints and other objective reasons that prevented us from recruiting enough rigid LSAD users. Some rigid LSAD may differ in usage and materials from flexible and semi-rigid types, and this type of LSAD is typically employed in real-life situations for severe lower-back pain conditions. Therefore, it is recommended that future research supplement the user experience of rigid LSAD and formulate service policies related to LSAD.

In order to drive subsequent improvements and developments in LSAD, it is essential to rely on collaborative efforts from researchers with diverse disciplinary backgrounds. Combining the results of our study, there may be insights that inspire professionals in medical engineering and designers in a related field.

For researchers in fields such as medical engineering:

Based on our research findings, tension tests for maximum and minimum effective wearing for different types or degrees of lower-back pain could be conducted. For example, researchers could visualize this intuitively on the LSAD through data visualization methods, as shown in Figure 7.

For designers in related fields:

The conceptual solutions we propose may not be perfect or the most suitable. Therefore, we suggest considering multiple rounds of design iteration based on these conceptual proposals to generate the optimal solution for mass production. Emphasis should be placed on our proposed LSAD design improvement recommendations, optimizing the LSAD design through concepts such as modular design, biomimicry, and adjustable features.

5. Conclusions

This study aimed to delve into the wearing experience of lower-back pain patients with LSAD and strove to propose universal design improvement recommendations for LSAD for this specific group. Through interviews and reflexive thematic analysis, we not only identified the needs and challenges of lower-back pain patients in using LSAD in their daily lives but also uncovered certain limitations in the existing LSAD designs. Design improvement considerations based on LSAD user experience include: (1) key design challenges to improving LSAD, (2) providing necessary assistance, and (3) individualizing needs and balance of design. Building upon this, we proposed a set of universal design improvement recommendations aimed at enhancing the user experience of LSAD and better meeting the needs of individuals with lower-back pain. These recommendations are expected to serve as a starting reference point for subsequent LSAD design improvements and developments.