Common Fascial Abnormalities in Five Thumb Pain Conditions: A Fifteen-Point Ultrasound-Guided Fascia Hydrorelease...

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.