Individuals who have undergone limb amputation face multiple physical, psychological, and socioeconomic challenges throughout their lives [1,2]. Chronic pain in the amputated limbs and joints of the unaffected limbs as well as lower back pain are common [3]. The prevalence of psychological comorbidities, including depression, anxiety, and post-traumatic stress disorder, varies between 13% and 71% depending on the study design and settings in the affected population [4-8]. An impaired quality of life and long-term disability can compromise the social integrity and financial security of the patients [9-11]. Interventions for patients who have undergone limb amputation include both pharmacological and nonpharmacological treatments, such as paraspinal and/or epidural nerve block, mirror therapy, and imaginary education [12-14]. However, evidence on the effects of individual treatment either as a standalone therapy or as a combination therapy remains limited, most likely due to the multiple symptom presentation and subsequent complexity of care, which are unlikely to be addressed by a single intervention in small-scale trials [12].

Traditional, complementary, and integrative medicine (TCIM) has long been an integral resource for healthcare and is used regularly globally [15]. Among the various types of TCIM, acupuncture is the most common form in 113 countries [15]. High-quality evidence indicates that acupuncture is effective for managing chronic pain [16] and improves patients’ quality of life [17]. A substantial number of the existing national clinical practice guidelines recommends the use of TCIM for managing chronic pain [18,19]. For amputees, previous systematic reviews have revealed that acupuncture and transcutaneous electrical stimulation may help manage phantom limb pain. However, the current level of evidence is low, indicating the necessity for further high-quality trials [20,21]. A recent randomized trial found that yoga, another popular form of TCIM, improved quality of life and psychological symptoms in individuals who had undergone traumatic lower-limb amputation in India [22]. Published anecdotes have described the benefits of TCIM either as a treatment combined with Western medicine [23,24] or as a standalone therapy [25]. However, studies investigating the roles of various TCIMs in individuals who have undergone limb amputation have not yet been conducted.

The risk of limb amputation, either due to poorly managed underlying pathologies such as diabetes or traumatic injuries, is higher in resource-limited settings than in high-income countries [26,27]. Under these conditions, TCIM may bridge the gap between the unmet needs of long-term post-amputation care and insufficient healthcare resources; however, the relevant evidence base is currently limited. In a case–control study investigating the association between musculoskeletal impairment and poverty in post-conflict Myanmar, 93% of the 108 individuals who had undergone lower-limb amputations had a lower quality of life than the non-amputee controls [28]. In a qualitative interview with lower-limb amputees in the same setting, some respondents revealed the use of traditional medicine before accessing primary or secondary healthcare services [29].

Given the limited information on the potential benefits of TCIM in amputees with substantial unmet needs, in terms of symptom management and functional improvement, a comprehensive scoping review of the available evidence on TCIM for amputees is warranted. In this respect, this scoping review aims to identify the types of available evidence in TCIM for patients who have undergone limb amputation.

The protocol of the present scoping review is based on the framework proposed by Arksey and O’Mally [30], which includes five stages. The recommendations made by Levac et al. [31] and Daudt et al. [32] will be used as references to increase the clarity of the review process and methodology. We will adhere to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for Scoping Reviews (PRISMA-ScR) when reporting our findings [33]. The protocol for this scoping review has been prospectively registered on the INPLASY platform (no. 202420019) [34].

1. Stage 1: identifying the research question

The primary research question is as follows: “What is the role of TCIM reported in individuals who have undergone limb amputation, regardless of underlying etiology?”

The research sub-questions are as follows: (1) In what circumstances, contexts, and settings has TCIM been reported in individuals who have undergone limb amputation? (2) Which types of TCIM and outcomes have been reported in patients who have undergone limb amputation? (3) Which types of study designs have been employed to assess the role of TCIM in individuals who have undergone limb amputation?

2. Stage 2: identifying relevant studies

We searched TCIM-related terms, including but not limited to acupuncture, moxibustion, cupping, traditional medicine, folk/alternative therapy, complementary therapies, mind-body interventions, herbal medicine, and hypnosis (i.e., group 1), and amputation-related terms, including but not limited to phantom limb pain, residual limb pain, stump pain, and amputation (i.e., group 2). The search terms for MEDLINE (via PubMed) are provided in Table 1, and the full search terms and search strategy are provided in Appendix 1. We searched published studies, unpublished theses, and ongoing trial information across MEDLINE (PubMed), Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), KoreaMed, the Oriental Medicine Advanced Searching Integrated System (OASIS), China Academic Journals (CAJ), and the World Health Organization (WHO) International Clinical Trials Registry Platform (WHO ICTRP) from their inception to September 19, 2023. The reference lists of the literature reviews were screened to retrieve potentially relevant reports (i.e., a backward citation check). For randomized trials, we will perform a forward citation search to identify relevant studies. No language restriction will be imposed, and studies reported in languages other than English will be translated using online translation tools, such as Google Translate, where necessary. Currently, the initial search and screening process have been completed. We will update the search on January 02, 2025 to reflect the most up-to-date evidence in the review using the same search strategy.

Table 1 . Search formula for MEDLINE via PubMed.

Number	Search terms
#1	acupuncture OR acupuncture therapies OR acupuncture treatment OR acupuncture treatments OR acupuncture points OR acupoints OR acupotomy OR acupotomies OR acupressure OR acupuncture analgesia OR acupuncture, ear OR electroacupuncture OR pharmacopuncture
#2	moxibustion OR moxa OR moxabustion
#3	medicine, korean traditional OR korean medicine OR medicine, chinese traditional OR drugs, chinese herbal OR Chinese herbal medicine OR chinese medicine OR medicine, kampo OR medicine, Mongolian traditional OR medicine, east asian traditional OR medicine, ayurvedic OR medicine, Arabic OR medicine, unani OR medicine, Tibetan traditional OR medicine, persian
#4	OR oriental medicine OR medicine, traditional OR indigenous medicine OR indigenous therapy OR folk medicine OR folk therapy OR alternative therapies OR alternative therapy OR complementary therapy OR complementary therapies OR homeopath
#5	chuna OR tuina OR tui-na OR "tui na" OR manipulation, spinal OR reiki OR reflexology OR yoga OR yogic OR massage OR "gua sha" OR tai chi OR taegeuk OR cupping OR herbal OR herb* OR herbal medicine OR phytotherapy OR plant extracts OR aroma OR mind body therapy OR mind-body OR mind body OR meditation
#6	#1 OR #2 OR #3 OR #4 OR #5
#7	amputation, traumatic OR multiple amputations, traumatic OR amputation, surgical OR amputation OR amputees OR residual limb OR stump OR phantom limb OR phantom limb pain OR phantom pain OR phantom sensation OR phantom sensations OR phantom phenomena OR phantom limb phenomena OR Mangled Extremity
#8	#6 AND #7

3. Stage 3: study selection

1) Eligibility criteria

Both uncontrolled observational studies, which report changes in conditions after TCIM treatment, and controlled trials, which compare TCIM with other interventions, will be eligible. Observational studies, including case reports, uncontrolled case series, cohort studies, and retrospective chart reviews, will be included. In addition, controlled trials, such as nonrandomized and randomized controlled trials, will be examined. However, preclinical studies, qualitative studies, studies on limb amputation prevention, study protocols, and studies on non-TCIM-based interventions will be excluded.

The other inclusion criteria are as follows: studies including adult patients with limb amputations regardless of the underlying etiology (e.g., both traumatic and nontraumatic); studies reporting on the clinical outcomes of TCIM interventions, including but not limited to acupuncture, moxibustion, cupping, traditional medicine, folk/alternative therapy, complementary therapies, mind-body interventions, herbal medicine, and hypnosis, for treating symptoms after limb amputation, whereas studies reporting on interventions for preventing limb amputation will be excluded; studies employing TCIM either as a standalone therapy or as part of a combination therapy; and studies comparing TCIM with any type of control interventions (randomized or nonrandomized controlled studies).

2) Study selection process

A researcher (KS) will search the aforementioned electronic databases to retrieve potentially relevant reports. Ten percent of the initially retrieved reports will be randomly sampled and independently screened based on the title and abstract by two researchers (KS and YO). After satisfying sufficient inter-rater agreement for screening (i.e., a kappa value ≥ 0.9), a researcher (KS) will complete the screening process. Full-text screening will be independently conducted by two researchers (KS and YO). A senior researcher (KHK) will arbitrate any disagreement between the two researchers during the screening process. The study selection process will be illustrated in accordance with the PRISMA flowchart, as shown in Fig. 1.

Figure 1. Study selection flowchart. CENTRAL, Cochrane Central Register of Controlled Trials; OASIS, Oriental Medicine Advanced Searching Integrated System.

4. Stage 4: data extraction

The present study is a scoping review; thus, we will not quantitatively estimate the effects of TCIM. Instead, we will descriptively summarize all reported clinical outcomes and the timing of outcome measures. The expected clinical outcomes will include pain associated with limb amputation, pain in the nonamputated body parts, sleep disorders, psychological health outcomes, dysfunction, and quality of life. The harmful effects of the TCIM interventions will also be descriptively illustrated. We will contact the corresponding author of the ongoing trials and gray literature via e-mail to request further information, if necessary.

5. Stage 5: collating, summarizing, and reporting the results

We will develop a predefined data extraction sheet for data extraction and management. We will qualitatively synthesize data based on the study design, context, population, intervention, comparator (if applicable), and outcomes (if applicable). Although formal pooled effect estimates will not be sought, the reported quantitative data will be summarized in the manuscript as appropriate. The results will be tabulated to illustrate the current evidence map on the role of TCIM in patients after limb amputation. The implications of our findings for clinical practice and future research will also be described. The bibliographic information and extracted data will be summarized using a Microsoft Excel spreadsheet (Microsoft). A predefined data extraction sheet per individual study will be used to document the characteristics of each study, which will be published as supplementary files. One researcher (KS) will manage and extract data under the supervision of the principal investigator (KHK). The descriptive characteristics of the included studies, such as the study design, population, intervention, comparator, and outcomes, will then be tabulated. A qualitative description of the data based on the types of clinical outcomes will also be provided. We will not assess the formal risk of bias for the included studies because the present investigation is a scoping review that aims to map the current evidence rather than critically appraise it. For acupuncture studies, the location of the acupoints, methods of needle stimulation, outcomes, and other relevant study characteristics will be extracted and analyzed separately to conduct a network analysis of acupuncture points used for post-amputation symptoms and other health conditions. The network analysis will be reported separately. No subgroup or sensitivity analysis will be performed.

6. Amendments

Any differences between the protocol and final review will be elaborated on in a point-by-point manner.

7. Dissemination

The results of this scoping review will be presented at relevant academic conferences and submitted to peer-reviewed journals. We will also disseminate our findings to the patients and public groups.

This scoping review aims to identify the types of existing evidence on the role of TCIM for various symptoms and health conditions in people who have undergone limb amputation. This paper will comprehensively map the types of TCIM interventions used in various clinical and sociocultural circumstances, as well as the types of outcomes of interest described in previous literature. This review will provide summary information on existing reports on the use of TCIM after limb amputation. Supplementary information on the characteristics of the included studies will serve as an information repository, which will help future researchers in designing high-quality studies on TCIM among the post-amputation population.

This review might have potential limitations. First, reports indexed in local databases, which are not included in the search in this review, may exist, although the authors will try to capture both existing and ongoing studies using a comprehensive search strategy. The risk of limb amputation due to either injuries or poor management of underlying diseases is likely to be higher in low- and middle-income countries than in high-income settings, whilst amputee population may have been under-represented in the existing literature. Thus, our findings may only reflect the current reporting on the use of TCIM in individuals with limb amputation rather than the actual practice of TCIM. Second, descriptive summaries will be provided, as the aim of this scoping review is to provide an overview of current evidence; therefore, any specific practical implications of findings for future research and clinical practice may not be drawn.

This review will highlight the current resources and type of evidence on the role of TCIM in patients who have undergone limb amputation. The study findings will inform healthcare professionals and researchers in identifying research gaps and obtaining insights into the role of TCIM in patients with limb amputation in various settings.

Conceptualization: KS, YO, SK, NHL, XH, KHK. Funding acquisition: KHK. Investigation: KS, KHK. Methodology: KS, YO, XH, YC, HM, KHK. Project administration: KHK. Supervision: KHK. Writing – original draft: KS, KHK. Writing – review & editing: YO, SK, NHL, YC.

The authors have no conflicts of interest to declare.

This work was supported by a 2-Year Research Grant of Pusan National University.

This research did not involve any human or animal experiment. The protocol of this scoping review has been registered in International Platform of Registered Systematic Review and Meta-analysis Protocols (INPLASY 20240019).