The Infinity Loop of Healthcare Innovation: Development of an Integrated Rehabilitation Pathway for Lumbar Fusion Surgery Through Design Thinking

Infinity loop of Design Thinking

Design thinking process

From November 2017 to March 2022, we adopted the infinity loop of design thinking, a revisualization of Stanford’s d.school framework, to design an evidence-based, integrated rehabilitation pathway for patients undergoing lumbar fusion surgery [2025]. The infinity loop includes five phases, which are non-linear (back-and-forth is possible), continuous (“trying to solve a problem can help you better understand it”), and user-centred: (i) Empathize, (ii) Define, (iii) Ideate, (iv) Prototype, and (v) Test. A visual summary of the design thinking process is provided in Figure 1.

Figure 1

This design thinking framework was strengthened by incorporating sound research methodologies from theoretical pathway and implementation frameworks [262728293031]. The design thinking process was reported in line with the ‘Guideline for reporting research involving design’ and the GUIDED statement [3233].

The aims, methods, and the key results of each phase of the infinity loop of design thinking are presented below. The results of the testing phase are outside the scope of this paper.

Empathize

The empathize phase aims to understand future end-users within the context of our design challenge: understanding their actions, motivations, needs, thoughts, and what is meaningful to them. This understanding is achieved by observing and engaging with end-users directly.

To accomplish this, two studies were conducted: a prospective cohort study exploring usual care and a qualitative descriptive interview study encompassing interviews with both patients and healthcare providers.

First, we observed the usual care of 36 patients undergoing lumbar fusion surgery and their clinical outcomes until one year postoperatively in a prospective cohort study [34]. Patients were aged between 18 and 75 years old, underwent single or double-level lumbar fusion surgery for degenerative conditions, and were followed-up until one year postoperative.

The prospective cohort study observed that patients experienced an improvement of back and leg pain following lumbar fusion surgery. However, a high score for kinesiophobia and disability remained present. One year postoperatively, only 56% of patients returned to work. This highlights the (unspoken) needs for tackling these underwhelming work resumption and high disability and kinesiophobia after lumbar fusion surgery [34].

In parallel, we engaged with patients and healthcare providers, in a qualitative interview study to gain a deeper understanding of how they perceive the current practices of lumbar fusion surgery and its rehabilitation, and what ingredients are deemed necessary for an optimal rehabilitation pathway from an end-user perspective [35]. Five patients who underwent lumbar fusion surgery and 31 healthcare providers from relevant disciplines participated in these semi-structured interviews. Healthcare providers were purposeful selected to ensure diverse expertise and work environments (academic and non-academic hospitals). Patients were purposeful selected from the orthopaedic and neurosurgery department within the academic hospital to capture varied patient demographics and clinical outcomes. The interview guide was reviewed by all members of the steering committee to ensure comprehensibility and relevance of the questions and refined during the interview process. The final interview guide covered open-ended questions regarding opinions on the current and optimal rehabilitation. Interviews were audio-recorded and transcribed verbatim. Qualitative analysis of the interviews followed the QUAGOL methodology and used NVivo software [3637].

The interviews revealed that healthcare providers disagreed on restrictions of postoperative activities, the optimal timing (preoperative, early or late postoperative) and content of postoperative physiotherapy, as well as the involvement of other disciplines in the rehabilitation process, thereby underlining the lack of consensus in current rehabilitation practice [35]. Additionally, patients and healthcare providers underlined the importance of interdisciplinary collaboration and an easy point of contact in the rehabilitation of patients. Within the interdisciplinary work setting, some healthcare providers perceived a professional hierarchy that restricted their ability to express their opinions freely [35].

Patients, on the other hand, encountered varying viewpoints from different healthcare providers, which generated uncertainty regarding their rehabilitation process and instilled fear regarding permitted movements. Importantly, both healthcare providers and patients did agree on the need for consensus amongst healthcare providers to ensure uniform messages towards patients [35].

Define

The define phase aims to formulate a meaningful and actionable problem statement, based on the insights into the spoken and unspoken needs and understanding of end-users during the empathize phase. The steering committee discussed and defined a specific problem statement for each end-user group (i.e., patients and healthcare providers) (Table 2). Novel elements in this problem statement after the empathize phase were the timeframe covered by, and characteristics of the needed rehabilitation pathway.

Ideate

The ideate phase aims to generate innovative ideas, based on the insights of the previous phases, and will provide the fuel and source material for building prototypes in the next phase.

To lay the foundation for an evidence-based rehabilitation pathway, two distinct research methods were employed. First, a systematic review and meta-analysis were conducted to comprehensively summarize the current scientific evidence on rehabilitation interventions that could enhance the clinical outcomes of patients undergoing lumbar fusion surgery [7].

The systematic literature search identified 18 randomized controlled trials, including 1402 unique patients, comparing rehabilitation interventions in the preoperative or postoperative period of lumbar fusion with usual care. Exercise therapy was found more effective in reducing disability and pain in the short-term (standardized mean difference [95% CI]: –0.41 [–0.71; –0.10] and –0.36 [–0.65; –0.08], respectively). If this was embedded in a multimodal rehabilitation program, a greater reduction in disability and fear avoidance was observed, compared to exercise alone (–0.31 [–0.49; –0.13] and –0.64 [–1.11; –0.17], respectively). Rehabilitation showed a positive tendency towards a higher return-to-work rate, compared to usual care (pooled relative risk [95% CI]: 1.30 [0.99; 1.69]. Therefore, we could conclude that an optimal rehabilitation pathway should likely be multimodal [7].

Second, we conducted a modified Delphi study comprising three iterative rounds and one face-to-face meeting [38]. We assembled an interdisciplinary expert panel consisting of 31 experts from Belgium and the Netherlands. Experts were purposeful selected based on their extensive clinical and research experience in the domains of low back pain, rehabilitation, and lumbar fusion surgery. Efforts were made to ensure a diverse representation of disciplines, gender, and primary work setting. The first round was based on the insights during the previous phases [3435], and on the results of the systematic review [7]. A predefined consensus threshold of 75% agreement was established a priori. In cases where consensus was not achieved, key interventions were rephrased based on experts’ feedback and reconsidered in subsequent rounds. Experts could also suggest additional key interventions to be included in subsequent rounds. The final expert consensus was validated by nine patients who underwent lumbar fusion surgery. These patients represented diverse demographic and outcome characteristics and were invited to participate in an online survey encompassing statements relevant to their experiences. Furthermore, seven of these patients engaged in a subsequent focus group, where they openly shared their experiences throughout the preoperative, perioperative, and postoperative phases. Full details of both studies are available elsewhere [738].

The modified Delphi study resulted in 122 key recommendations for optimal pre-, peri- and postoperative rehabilitation, endorsed by experts and validated by patients [38]. These recommendations include innovative components such as prehabilitation, early postoperative mobilization, easy access to a case manager, uniform communication through leaflets, videos and website, and limited postoperative activity restrictions. An explicit need for return-to-work guidance was formulated during the patient validation of the recommendations [38].

Prototype

The prototype phase aims to transform ideas generated in the previous phase into tangible prototypes that allow designers to visualize and refine possible solutions.

An initial prototype was developed based on the end-users’ needs (empathize phase), rehabilitation pathway needs (define phase), and the building blocks from best-evidence, expert-consensus, and the feedback of patients (ideate phase). For this, the rehabilitation recommendations that gained expert-consensus during the modified Delphi study were categorized into key interventions and subcomponents. These key interventions were clustered into three time periods: the pre-, peri- and postoperative phase, and translated into a pathway. This was presented in the form of a time-task flowchart using Visio software, adhering to the principles of process mapping [39].

This time-task flowchart was first piloted in the interdisciplinary steering committee, where gaps and areas needing improvement were defined. Second, parts of this prototype (‘small scale prototypes’) were discussed separately on an iterative basis with the relevant supporting experts, in mono- or interdisciplinary groups. For example, the postoperative restrictions were discussed separately with the surgeons, then separately with the physiotherapists, and finally with surgeons, physiotherapists and specialists in physical and rehabilitation medicine together. These discussions started with a brainstorming session (i.e., iterative prototyping, defining areas needing improvement or additional needs and ideating new possibilities when an idea fails) and moved forward until consensus within the small supporting groups was obtained (i.e., prototyping a part of the rehabilitation pathway). Third, the final rehabilitation pathway prototype (‘full scale prototype’) was once more critically evaluated and adapted by the interdisciplinary steering committee.

As part of this process, various design supporting tools were developed for the newly developed rehabilitation pathway. These included an educational leaflet, an information leaflet for physiotherapists, an information leaflet for general practitioners, educational videos, a comprehensive website, an index card for intramural healthcare providers, and interactive educational sessions for healthcare providers. For each of these tools, a short design thinking process at microlevel was undertaken in the appointed supporting groups. Drawing upon the insights garnered from the extensive empathize and ideate phases mentioned above, brainstorming sessions in the relevant supporting groups defined the needs and desires for each tool and strengthened additional ideating. Iterative prototyping with refinement ensured that the tools aligned seamlessly with the objectives and requirements of the aimed rehabilitation pathway.

Test

Testing of the rehabilitation pathway prototype is currently ongoing as part of a hybrid type 1 trial in a tertiary hospital setting to evaluate both real-world effectiveness and implementability (ClinicalTrials.gov NCT03427099). This is a nonrandomized controlled trial, where the prospective cohort of 36 patients receiving usual care (followed up during the initial empathize phase) serves as the control group. The intervention group includes patients undergoing single- or double level lumbar fusion surgery for degenerative conditions, and all healthcare providers involved in the management of these patients. The results of the testing phase, both the effectiveness and the implementability evaluation, will be presented in forthcoming research papers [6061].

The infinity component

During the testing phase, iterative feedback loops will inform refinements in the rehabilitation pathway and its implementation. Moreover, the testing phase allows us to learn more about the barriers and facilitators of implementing this rehabilitation pathway from the perspective of end-users and legislation, which will inform further refinements.

The steering committee and the supporting group prepared the implementation of the rehabilitation pathway, and continuously evaluate and improve this by additional loops of design thinking: learning about barriers and facilitators (empathize and define) ask for additional solutions (ideate, prototype and test).

Clinical innovation

This rehabilitation pathway intends to serve as a unifying guideline for patients undergoing lumbar fusion surgery, across disciplines, across care settings, and across the entire time-continuum of care (i.e., pre-, peri- and postoperatively).

The introduction of prehabilitation, which is also gaining interest in the context of other surgical procedures, sets the stage for a proactive approach that empowers patients early on as active participants in their own care [43]. In this proactive approach, a case manager plays a key role as a central point of contact and a person of trust. Prehabilitation can give patients a head start for a better postoperative recovery after lumbar fusion surgery by focusing on education, intake of physiotherapy and interventions to address potential risk factors. In doing so, this pathway expands on the existing evidence base, where risk factors for suboptimal postoperative recovery have been identified, but therapeutic implications were limited [44454647484950]. By emphasizing early postoperative mobilization, consistent with the Enhanced Recovery After Surgery recommendation [51], the pathway encourages patients to start moving as soon as possible after surgery. In the postoperative phase, the rehabilitation pathway promotes a rapid return to functional activities by allowing low to moderate axial loading immediately after surgery, by not prescribing postoperative braces, and by scheduling radiographs only when clinically indicated. This contrasts with current practices that often involve strict activity restrictions [12], postoperative bracing [13], and routine radiographs [52] unsupported by robust evidence.

Importantly, this rehabilitation pathway offers a standardized, yet flexible pathway, that may be tailored to individual patient needs. While rehabilitation, by its very nature, is a highly patient-centred strategy, the possibility to tailor rehabilitation was often absent in previously developed rehabilitation interventions [7].

Methodological innovation

Empathy for end-users forms the centrepiece of design thinking [21]. As researchers, the problems we try to solve are rarely our own, which can possibly lead to a mismatch between the research focus and the actual needs of end-users. Despite increasing encouragement to involve patients as partners in recent years, this remains the exception in clinical pain research [53].

The “empathize” phase revealed crucial insights that shaped the development of the rehabilitation pathway. For instance, the problem statement was redefined when it became evident that the rehabilitation process should encompass the entire patient journey and not only the postoperative phase. Additionally, the rehabilitation pathway needed to be standardized across disciplines, involving the primary care setting as well. The empathetic approach revealed that some healthcare providers felt undervalued in interdisciplinary meetings. To mitigate potential authority bias, we also included monodisciplinary iterations during prototyping, aiming to ensure equal value for all perspectives.

Incorporating robust research methodologies, such as a systematic review with meta-analysis and a modified Delphi study, into the design thinking framework, aimed to strengthen the evidence-based foundation of the resulting rehabilitation pathway.

Although it might seem intuitive to utilize current evidence when designing new interventions, this is often not the case [54]. Worryingly, previous research has revealed that less than half of researchers acknowledge being aware of relevant reviews regarding existing evidence while designing their clinical trials [55], and that even in highly cited medical journals, researchers seldom indicated the incorporation of recent systematic reviews into their trial design [54]. Neglecting established evidence may result in unfounded research and wasted efforts, further contributing to the issue of global research waste. In an era of increasing investment in biomedical research, which reached $240 billion USD in 2010, the need to reduce (avoidable) research waste is imperative. Research waste is reported to emerge when future users’ needs were ignored (lack of empathy), and what we already know or have studied was overlooked (lack of evidence review) [54].

Design thinking is a replicable method that could be useful in different contexts. Our paper’s strength lies in the transparent and rigorous reporting of our design thinking process. This can guide researchers in the adoption of design thinking for development of rehabilitation pathways for other types of surgery or health conditions. The World Health Organization (WHO) has recognized the increasing global need for rehabilitation, and prioritized it through the ‘Rehabilitation 2030: a call to action’ initiative, which aims to promote well-being and healthy lives [56]. With the potential to benefit a substantial portion of individuals living with disability, addressing this rehabilitation need is critical [56]. Researchers are urged to fill the knowledge gaps in rehabilitation [5657]. Developing real-world rehabilitation interventions has methodological challenges due to a dynamic and variable environment, unlike the constant enclosed environment of, for example, a petri dish for developing new antibiotics [515253]. Design thinking, with its user-centred and flexible approach, has the potential to adapt to the ever-changing healthcare landscape [2158].

Future directions include testing the rehabilitation pathway in a hybrid type 1 trial [59]. Such a hybrid design will evaluate the effectiveness and the implementability of the rehabilitation pathway.

A cost-utility analysis should be an essential part of the effectiveness evaluation. During the ideate phase of our pathway, no financial constraints were considered, which allowed for creative and out-of-the-box ideas. During the prototype phase, some financial barriers were considered to improve the potential for implementation.

To improve the implementation potential, a final recommendation is to involve health insurers in future refinements. The infinity aspect, or ‘design-post-design’, of design thinking makes it possible to do so.