‘De Quervain’s Tenosynovitis’ Causing Sharp Pain on the Thumb Side of the Wrist: Peritendinous Stem Cell Conditioned Media Injection as an Option — Dr. Moriwaki Organizes the Limits of Repeated Steroid Injections for This Stenosing Tenosynovitis Common in Women During Pregnancy, Postpartum, and Menopause2026.07.24

‘A sharp pain shoots through the thumb side of my wrist every time I lift my baby.’ ‘Excruciating pain runs through my hand when I try to open a bottle cap.’ Many women who visit our clinic with these symptoms are diagnosed with de quervain’s tenosynovitis. The cause of the pain lies in chronic inflammation and tendon degeneration occurring in the ‘first dorsal compartment’ on the radial side of the wrist, through which two tendons that move the thumb pass. It is a type of stenosing tenosynovitis that significantly restricts daily activities. This article, from Dr. Moriwaki’s perspective at AVAN TOKYO Ginza, organizes the option of peritendinous stem cell conditioned media injection as a conservative treatment, alongside the limits of the steroid injections that tend to be repeated.

Key Points of This Article

・De quervain’s tenosynovitis is a stenosing tenosynovitis that causes pain from the base of the thumb along the radial side of the wrist, most common in women during pregnancy, postpartum, and menopause

・Chronic inflammation and tendon degeneration of the first dorsal compartment (extensor pollicis brevis and abductor pollicis longus) underlie the pain

・Local steroid injection, the traditional mainstay, is effective for short-term pain relief but repeated use carries risks of tendon weakening and subcutaneous atrophy

・Peritendinous stem cell conditioned media injection is a new conservative option that may act on the inflammatory cycle and the peritendinous repair environment

・Response varies among individuals; splinting, occupational therapy, and lifestyle modification form the foundation. Differential diagnosis from carpal tunnel syndrome and thumb CMC arthritis is essential

What Is Actually Happening in De Quervain’s Tenosynovitis

This condition is a tendinopathy in which the extensor pollicis brevis and abductor pollicis longus, passing directly above the radial styloid process, repeatedly rub within a tunnel called the ‘first dorsal compartment,’ generating chronic inflammation and tissue degeneration in the tendons and tendon sheath. Pain is strongly provoked by clenching the thumb and ulnarly deviating the wrist, significantly limiting daily activities such as housework, childcare, and smartphone use.

Anatomy of the First Dorsal Compartment and the Friction Mechanism

Anatomically, the tunnel of the first dorsal compartment is often known to be divided into separate sub-compartments by a ‘septum’ on the inside, and the presence of this septum tends to increase friction between the tendons and sheath. The more frequently the thumb is used, the higher the pressure inside the tunnel becomes, the tendon sheath thickens, and a stenosing inflammatory cycle sets in. For information on joint and tendon conditions, please also refer to the Japanese Orthopaedic Association website.

Why Is It More Common in Women During Pregnancy, Postpartum, and Menopause?

Clinically, this condition is known to be more common in women, especially those in their 30s to 50s. During pregnancy and lactation, rapid changes in the hormonal environment, combined with repeated motion of ‘lifting the infant in a radially deviated position,’ concentrate the load on the first dorsal compartment. After menopause, decreased estrogen alters the water-retention capacity of tendons, ligaments, and sheaths, as well as collagen metabolism, creating an environment where tendon tissue itself is prone to degeneration. Given this background, the condition should not be understood as merely a matter of ‘overuse’ but as a multifactorial tendinopathy in which intrinsic tissue changes and external load overlap.

Limits of Local Steroid Injection and the Shift from ‘Inflammation’ to ‘Degeneration’

Strong Short-Term Pain Relief, But Not Repeatable

Local steroid injection into the first dorsal compartment is one of the standard treatments, showing high efficacy for short-term pain relief and reduction of tendon sheath swelling. However, when repeated multiple times a year at the same site, side effect risks such as weakening of the tendon tissue itself, subcutaneous fat atrophy, and skin depigmentation accumulate. Since tendon weakening can, in the worst case, lead to subcutaneous rupture, general orthopedic guidelines emphasize ‘avoiding repeated injections at the same site over short intervals.’

The Shift Toward Understanding as ‘Tendon Degeneration’

In recent years, the understanding of chronic tendinopathies has been shifting from simple ‘inflammation (tendinitis)’ to ‘tendon degeneration (tendinosis).’ In chronic de quervain’s tenosynovitis, microscopic findings such as disorganized collagen fibers, increased neovascularization, and mucoid degeneration have been confirmed. It has become clear that treatments that merely suppress inflammation are unlikely to promote structural recovery of the tendon tissue itself. Stem cell conditioned media, which aims to simultaneously target both anti-inflammatory action and repair environment restoration, is positioned as a new option here.

The ‘Repair Environment’ Targeted by Peritendinous Stem Cell Conditioned Media Injection

Layers Where Growth Factors and Cytokines Act

Stem cell conditioned media contains various growth factors such as TGF-β, IGF-1, FGF, and VEGF, along with cytokines with anti-inflammatory action. In peritendinous injection for this condition, these secreted factors are theoretically expected to calm the inflammatory cycle around the tendon while activating fibroblasts responsible for collagen synthesis and acting on the microcirculation of the originally hypovascular tendon tissue. While steroids strongly act to ‘suppress inflammation,’ stem cell conditioned media approaches from the direction of ‘preparing the tissue repair environment’ — fundamentally different in the axis of action.

Honest Positioning and Limits

However, at present there are no large-scale randomized controlled trials proving the efficacy of stem cell conditioned media for de quervain’s tenosynovitis. Clinically, it is realistically positioned as one of the options to consider in cases where repeated steroid injections are difficult, where splinting and rest do not provide sufficient improvement, or where an additional conservative treatment is desired before proceeding to surgery. Response varies among individuals, with reactions greatly affected by chronicity, degree of degeneration, and daily activity load. Please also see this page for more on stem cell conditioned media joint injections.

Treatment Does Not End with ‘Injection Alone’ — Splinting, Occupational Therapy, Differential Diagnosis

Thumb Spica and Reviewing Daily Movements

The foundation of treatment for this condition, prior to injection, is always placed on ‘reducing mechanical load on the first dorsal compartment.’ Wearing a ‘thumb spica splint’ that immobilizes the thumb (excluding the IP joint) and restricts ulnar deviation of the wrist, occupational instruction to avoid lifting the infant in a radially deviated position, and changing IT device habits such as switching smartphone scrolling from frequent swiping to tapping — these greatly affect the effect of injection alone.

Differential Diagnosis from Carpal Tunnel Syndrome and Thumb CMC Arthritis

Radial-side wrist pain has several conditions to be differentiated besides de quervain’s tenosynovitis, including thumb CMC arthritis, non-union after scaphoid fracture, some cases of carpal tunnel syndrome, and entrapment of the superficial branch of the radial nerve. In particular, cases where the ‘joint itself’ at the base of the thumb hurts require evaluation for thumb CMC arthritis first, and cases with numbness or nocturnal pain require evaluation for carpal tunnel syndrome first. When peritendinous injection does not produce a response, we would like to emphasize that re-examining the diagnosis is the top priority.

Frequently Asked Questions

Q. How many peritendinous injections of stem cell conditioned media are typically needed?

The appropriate number of sessions varies depending on the chronicity of symptoms, degree of degeneration, and daily activity load, and cannot be determined uniformly. As a guideline, we objectively evaluate pain scores, thumb range of motion, and pain during daily activities 4 to 8 weeks after the initial injection to determine whether additional administration is needed. Response varies among individuals, and combination with splinting and occupational instruction affects the response.

Q. Can I receive the injection if I just had a steroid injection?

We consider the interval after evaluating the effect assessment period of the most recent local steroid injection and the state of the local tissue. Because short-interval consecutive injections of different drugs at the same site place a heavy burden on the tissue, it is generally common to allow at least several weeks between them and observe the course.

Q. Can I receive peritendinous injection while breastfeeding?

Although this is local administration with limited systemic absorption expected, sufficient evidence regarding use during breastfeeding has not been established. We recommend that breastfeeding mothers first fully try alternative therapies (splinting and occupational instruction) after consulting with their primary physician.

Q. How soon can I expect to feel the effect?

Because changes in the tendon repair environment take time, this is not a treatment expected to provide dramatic pain relief immediately after injection. Clinically, we follow changes in pain and function over weeks to months, and when changes are poor, we shift to re-evaluation of the diagnosis and reconsideration of the treatment strategy.

Q. I am considering surgery. Is it safe to continue conservative treatment with injections?

If splinting, lifestyle guidance, and multiple sessions of conservative therapy do not produce clear improvement, or if disruption of daily activities continues, surgical release of the tendon sheath is an established option. Peritendinous injection should be considered as an option that expands the range of conservative treatments, not as a treatment that necessarily avoids surgery.

──────────────

Medical Supervisor: Dr. Shin Moriwaki

Japan Society of Aesthetic Surgery (JSAS) Member / American Academy of Aesthetic Medicine Member

US Medical License Qualification (ECFMG certificate)

──────────────

📍AVAN TOKYO Ginza Regenerative Medicine

English / 中文 / Tiếng Việt supported

Consultations available via DM / LINE / Website / Phone.