Background/Objectives: Ultrasound-guided fascial hydrorelease (FHR) occasionally elicits a brief localized contraction (“local twitch”) at the moment the needle tip contacts a fascial layer; the anatomical basis of this reaction has not yet been systematically characterized. To examine local twitch occurrence relative to stacking fascia (yes/no) at the needle tip (primary outcome), as well as the anatomical distribution and per-video capture rate (secondary outcomes). Methods: We retrospectively analyzed 11,205 ultrasound videos from a single pain clinic (October 2015–March 2026). Twitches were identified by prospective clinical observation and computational screening (frame-difference-based Profile Match classifier; 417 candidates over 30 review rounds). The stacking fascia status was independently determined by two FHR-experienced clinicians, with discordant cases jointly adjudicated. Results: Inter-rater agreement was 86/90 (95.6%; 95% CI 89.0–98.8%); one case was reassessed, deemed to not be a twitch, and excluded. In the final cohort (n = 89), local twitches occurred at stacking fascia in 89/89 (100%; 95% CI 95.9–100%). Events were concentrated in gluteal/pelvic (51%) and lumbar paraspinal (29%) regions, with a per-video capture rate of 0.98% (110/11,205; 95% CI 0.81–1.18%). Conclusions: Local twitches during ultrasound-guided FHR essentially always coincide with the needle tip lying within stacking fascia, identifying this as the structural locus within this cohort. This figure represents inclusion-criterion-bound selectivity within the twitch-positive subset, not the positive predictive value of stacking fascia for twitch occurrence.

Ultrasound-guided fascial hydrorelease (FHR) has been reported to provide sustained pain relief in patients with chronic musculoskeletal pain; however, its underlying biological mechanisms remain incompletely understood. In this review, we propose the “Fascial Memory Reset Hypothesis” as an integrative framework linking mechanobiology, extracellular matrix (ECM) remodeling, peripheral nociception, microcirculatory dynamics, and ultrasound imaging findings. Mechanobiological research has demonstrated that increased tissue stiffness activates YAP/TAZ signaling, promoting fibroblast activation, ECM deposition, and mechano-epigenetic regulation. These mechanically driven processes can stabilize pathological tissue phenotypes without DNA sequence alterations. The “Fascial Memory Reset Hypothesis” proposes that targeted mechanical interventions such as FHR may partially reverse these mechanically maintained states by restoring tissue mobility and modifying stiffness-dependent mechanotransduction. We introduce “stacking fascia” as an ultrasound-visible layered structural phenotype reflecting cumulative mechanobiological adaptation. Integrating molecular mechanotransduction pathways, mechano-epigenetic mechanisms, neural sensitization, and vascular factors, we propose that FHR may hypothetically partially normalize pathological fascial states by mechanically restoring tissue mobility and modifying stiffness-dependent signaling. Although direct molecular evidence of the effect of FHR in human fascia remains limited, this hypothesis provides a biologically plausible link between mechanical stress, ultrasound-visible structural alterations, and sustained clinical improvement.

Background: Thumb pain frequently arises from multiple conditions—de Quervain’s tenosynovitis, carpometacarpal (CMC) osteoarthritis, carpal tunnel syndrome, intersection syndrome, and myofascial pain syndrome—that often coexist yet are traditionally managed as separate entities. Fascial abnormalities, including hyaluronic acid-related densification and impaired interlayer gliding, have been proposed to constitute a shared pathological substrate underlying these conditions. Ultrasound-guided fascia hydrorelease (US-FHR) targeting fascial pathology has been used clinically for thumb–wrist pain; however, the anatomical targets and treatment regions have not been systematically described. Aim: This article presents a fifteen-point US-FHR clinical protocol for five converging thumb pain conditions, based on shared fascial abnormalities—densification and impaired interlayer gliding—that these conditions may have in common. It further provides a shared practical framework for pain physicians, orthopedic specialists, hand therapists, and acupuncturists. Methods: The protocol was organized based on a focused literature review on fascial biology, thumb–wrist anatomy, and the five converging conditions, combined with long-term clinical experience at Kimura Pain Clinic. For each POINT, the anatomical rationale, associated pain pattern, procedural concept, and major safety considerations were summarized. A four-direction screening test (thumb flexion, extension, abduction, and adduction) assessed in three modes (active contraction, resistance loading, and passive stretch), combined with nine established clinical tests, was integrated to identify the affected fascial structures. A diagnostic ultrasound finding characterized by multi-layered hyperechoic bands with reduced interlayer gliding—the sonographic appearance termed “stacking fascia” (a hyperechoic, stripe-shaped lesion), a previously described morphological sign that may reflect fascial densification—is described. Results: The protocol comprises 15 POINTs distributed across two approaches: nine POINTs via a dorsal approach and six POINTs via a palmar approach. The dorsal approach (9 POINTs) covers the first and third extensor compartments, their intersections (1st–2nd and 2nd–3rd), the two radial-artery crossing points (Points 5 and 6, where the radial artery passes deep to the first-compartment and EPL/ECRB–ECRL tendons, respectively), Gokoku (Hegu), the adductor pollicis, and the deep palmar arch. The palmar approach (6 POINTs) covers the thenar muscles, transverse carpal ligament, paraneural sheath and interfascicular epineurium of the median nerve, the median-nerve/FPL/FCR interface, the median nerve within the carpal tunnel, and the deeper palmar ligamentous structures adjacent to the median nerve. Periarterial release around the radial artery is proposed as a hypothesis-generating approach to CMC osteoarthritis, in which fascial constriction of periarterial tissue may contribute to subchondral vascular compromise. For each POINT, the anatomical rationale, associated pain patterns, procedural concept, and safety considerations are integrated and described. Conclusions: The proposed fifteen-point protocol represents an expanded, structured, and clinical-experience-based framework for US-FHR in five converging thumb pain conditions sharing common fascial abnormalities. It may serve as a practical basis for the standardization, education, and broader dissemination of US-FHR in this population. Prospective observational studies, randomized controlled trials, and imaging validation studies are needed to evaluate its clinical effectiveness and to test the underlying mechanistic hypotheses, including potential periarterial vascular contributions to CMC osteoarthritis.

Ultrasound-guided fascial hydrorelease (FHR) occasionally elicits a brief localized contraction ("local twitch") at the moment the needle tip contacts a fascial layer; the anatomical basis of this reaction has not yet been systematically characterized. To examine local twitch occurrence relative to stacking fascia (yes/no) at the needle tip (primary outcome), as well as the anatomical distribution and per-video capture rate (secondary outcomes), we retrospectively analyzed 11,205 ultrasound videos from a single pain clinic (October 2015–March 2026). Twitches were identified by prospective clinical observation and computational screening (frame-difference-based Profile Match classifier; 417 candidates over 30 review rounds). The stacking fascia status was independently determined by two FHR-experienced clinicians, with discordant cases jointly adjudicated. Inter-rater agreement was 86/90 (95.6%; 95% CI 89.0–98.8%); one case was reassessed, deemed to not be a twitch, and excluded. In the final cohort (n = 89), local twitches occurred at stacking fascia in 89/89 (100%; 95% CI 95.9–100%). Events were concentrated in gluteal/pelvic (51%) and lumbar paraspinal (28%) regions, with a per-video capture rate of 0.98% (110/11,205; 95% CI 0.81–1.18%). Local twitches during ultrasound-guided FHR essentially always coincide with the needle tip lying within stacking fascia, identifying this as the structural locus within this cohort.

Background/Objectives: Non-specific low back pain (LBP) is multifactorial, and psychosocial factors are often important. Densified fascial tissues of the thoracolumbar and lumbogluteal fascial system, seen as “stacking fascia,” may represent one under-recognized and treatable peripheral source; routine imaging assesses the disc, vertebra and nerve root but not these tissues [1]. The release points presented are representative examples, not an exhaustive list. The objective is to present a standardized, multi-point ultrasound-guided fascia hydrorelease (US-FHR) protocol for the fascia-derived component of LBP, identified by the Fascial Pain Syndrome (FPS) criteria [2] and a stacking-fascia appearance on ultrasound, after exclusion of red-flag disease and clear radiculopathy. Methods: A Protocol Development Framework (narrative synthesis of anatomy, neurophysiology and the authors’ clinical experience; no new prospective dataset) was used to define diagnosis/evaluation, the US-FHR procedure and a region-based multi-point protocol. Results: Fifteen release points, ordered from the lower thoracic to the sacroiliac region, cover the thoracic paraspinal/latissimus–TLF continuity, serratus posterior inferior, diaphragm–quadratus lumborum interface at Th12, lumbar interfascial triangle, quadratus lumborum, psoas major at L2, lumbar plexus, posterior midline ligaments, thoracolumbar fascia, multifidus and peri-facet fascia, iliolumbar ligament, ligamentum flavum/flavum–facet point, superior cluneal nerve, gluteus medius and superior gluteal artery, and posterior sacroiliac ligament. Each point is described by anatomical rationale, referred-pain pattern, technique concept and safety, with a representative ultrasound still. Conclusions: The protocol describes a peripheral component of LBP that may be identifiable and treatable, and is offered as the methodological basis for a planned prospective study distinct from the single-site TLF pilot NCT06818175 [3].

Background and Objectives: Non-odontogenic toothache often persists without an identifiable dental cause and may lead to unnecessary pulpectomy or tooth extraction. It may also result in long-term combined use of psychotropic medications, forming a recurrent clinical pattern. Ultrasound-guided fascia hydrorelease (US-FHR) targeting fascia-derived pathology has been applied to non-odontogenic toothache; however, treatment regions have not been systematically described. This article presents a proposed eleven-point US-FHR protocol for non-odontogenic toothache and related orofacial pain. Materials and Methods: This is an experience-based clinical protocol; it is not an efficacy study and does not include a new prospective study on human participants. The protocol was organized on the basis of long-term clinical experience at Kimura Pain Clinic and a focused literature search. Results: The protocol comprises 11 POINTs distributed across six anatomical regions: (1) three POINTs in the masticatory muscle region, (2) three POINTs in the medial pterygoid and capsular region, (3) one POINT in the parotid region, (4) two POINTs in the cervical region, (5) one POINT in the facial-artery region, and (6) one POINT in the upper posterior cervical region. For each POINT, the anatomical rationale, referred-pain pattern, procedural concept, and safety considerations are described. Conclusions: The proposed eleven-point protocol represents an expanded and structured development of the earlier four-region approach. Prospective, ideally controlled, studies are needed to evaluate its clinical effectiveness.