Letter Comments on: Effect of Contralateral Acupuncture (Geoja Technique) in Musculoskeletal Disorders Stratified by Pulse Strength Differences: A Retrospective Study [Letter]

Dear editor

We have carefully read the retrospective study titled “Effect of Contralateral Acupuncture (Geoja Technique) in Musculoskeletal Disorders Stratified by Pulse Strength Differences”¹ published in the Journal of Pain Research with great interest. This study explores the application of the “Geoja Technique”—a therapy rooted in traditional Korean Medicine (KM) and derived from Huangdi Neijing (Yellow Emperor’s Inner Canon) and Donguibogam² (Treasury of Eastern Medicine)—for unilateral musculoskeletal pain. It attempts to investigate the efficacy patterns through stratification based on pulse strength differences, providing insights for the modern research of traditional acupuncture techniques. However, from the perspectives of the rigor of clinical research methodology, the generalizability of results, and the value of clinical translation, the study still has several key issues that require further refinement. We discuss these issues below to provide references for future research.

Lack of Standardization in Pulse Diagnosis: Deviating from the Classical Connotations of Korean Medicine

The study uses “differences in pulse strength between the left and right wrists” as the core stratification criterion and claims to follow the theories of Huangdi Neijing and Donguibogam. Nevertheless, the classical pulse diagnosis system in traditional Korean Medicine is a systematic assessment encompassing pulse position (depth), pulse shape (wiry pulse, slippery pulse), pulse rate (frequency), and pulse rhythm. It cannot be reduced to the single indicator of “pulse strength.”² As recorded in Donguibogam·Maiyao (Essentials of Pulse Diagnosis): “To diagnose the pulse, one must first distinguish the pulse position (superficial, middle, deep), then observe the pulse shape and rhythm, and finally examine the pulse strength to correlate with disorders of the zang-fu organs”.

This study only evaluates “pulse strength” while ignoring other key characteristics of the pulse condition—it fails to clarify whether the pulse strength difference occurs at the Chon (distal), Gwan (middle), or Cheok (proximal) position, nor does it associate pulse strength differences with the affected meridians (a stronger left Gwan pulse corresponding to Liver Meridian disorders, or a stronger right Gwan pulse corresponding to Spleen Meridian disorders).

Limitations in Study Design: Insufficient Representativeness of Cases and Unaddressed Interference from Combined Treatments

The study does not clearly document patients’ medical history, including whether they have underlying diseases such as diabetes or osteoporosis, and whether they have previously received acupuncture or medication. In clinical practice, peripheral neuropathy in diabetic patients may affect the analgesic effect of acupuncture; the absence of such key variables reduces the representativeness of the study sample.

Additionally, the study adopts an intervention approach of “30 minutes of synchronous infrared therapy during acupuncture” but fails to evaluate the independent efficacy of infrared therapy alone for musculoskeletal pain. This makes it impossible to distinguish whether the final efficacy is attributed to the “acupuncture effect of the Geoja Technique”, the “warming effect of infrared therapy”, or the “synergistic effect of both”. From the perspective of traditional Korean Medicine theory, the warming effect of infrared therapy can be categorized under “warming and unblocking meridians”, which itself can alleviate musculoskeletal pain caused by “cold congelation and qi stagnation”. Modern studies have also confirmed that infrared therapy relieves muscle soreness by promoting local blood circulation and reducing inflammatory responses. This combined intervention design prevents the study from defining the specific therapeutic effect of acupuncture.

Non-Operationalized Syndrome Differentiation Criteria and Lack of Efficacy Analysis by Syndrome Type

As a core therapy in traditional Korean Medicine, acupuncture is guided by the principle of “integrating disease diagnosis with syndrome differentiation”. Individual differences in constitution significantly influence the therapeutic effect of acupuncture: patients with a cold-deficiency constitution may have lower sensitivity to De-qi (the arrival of qi, a key response to acupuncture) due to “insufficient yang qi and impaired warming function”, requiring prolonged needle manipulation or adjusted techniques; patients with a dampness-retention constitution may need additional acupoints for dispelling dampness and unblocking meridians due to “meridian obstruction by phlegm and dampness”. However, based on the theory of the “Five Shu-points”, this study adopts a standardized protocol of “tonifying Water points (+) and reducing Fire points (-)” for all patients with meridian-related pain, using “pulse strength difference” as the sole stratification criterion while ignoring the potential correlation between constitution and efficacy. This not only deviates from the core concept of “individualized treatment” in traditional Korean Medicine but also fails to identify the advantages of the Geoja Technique in patients with specific syndromes, limiting the clinical guiding value of the study’s conclusions.

Lack of Korean Medicine-Oriented Efficacy Evaluation Indicators

The study uses Western medical indicators—the Numerical Rating Scale (NRS) and Range of Motion (ROM)—to assess efficacy, while neglecting outcome indicators characteristic of traditional Korean Medicine. In clinical practice of traditional Korean Medicine, the efficacy of acupuncture should be evaluated based on the comprehensive criteria of “symptoms-pulse-signs” specified in the Korean Medicine Clinical Practice Guidelines (CPGs).³ By focusing solely on changes in pain scores and joint movement angles, this study lacks such evaluation dimensions and fails to capture the regulatory effect of the Geoja Technique on “the state of meridian qi and blood”—a core aspect of efficacy assessment in traditional Korean Medicine—resulting in an incomplete judgment of therapeutic effects.

Recommendations for Future Research

To better integrate traditional Korean Medicine theory with modern scientific methodology and enhance the scientific rigor and clinical value of research, we propose the following recommendations:

1. Standardize pulse diagnosis: Combine subjective palpation with objective tools (pulse wave analyzers) and test inter-rater reliability.
2. Conduct prospective studies: Expand the sample size, stratify patients by “underlying diseases” and “Korean Medicine syndromes”, and establish control groups such as the “acupuncture-only group” and “infrared therapy-only group” to eliminate interference from combined treatments.
3. Improve the meridian syndrome differentiation system: Document detailed information on lesion locations and accompanying symptoms, clarify the association between meridian identification, pulse condition, and constitution, and guide individualized acupoint selection.
4. Establish a composite efficacy evaluation system: Integrate “traditional Korean Medicine symptom indicators” with “Western medical functional indicators” to comprehensively assess therapeutic effects.

We anticipate that subsequent studies will address the aforementioned limitations and provide more robust evidence to support the clinical application of the Geoja Technique.