Trigger Finger (Stenosing Tenosynovitis)

Trigger finger is a finger or thumb that catches, clicks or locks as it bends and straightens. The medical name, stenosing tenosynovitis, describes a narrowing (stenosis) where a tendon runs through its sheath. The problem sits at a small band of tissue at the base of the finger, the first annular pulley, usually called the A1 pulley. When the tendon and this pulley no longer match in size, the tendon jams, and then snaps through. This page describes what researchers have found inside the affected pulley, how the condition is graded, who gets it, how it is diagnosed, what the trials of splints, injections and surgery report, how trigger thumb in young children differs from the adult condition, and what is still not known.

Table of Contents

  1. What Happens Inside the Finger
  2. Symptoms and the Severity Grades
  3. How Common It Is and Who Gets It
  4. How It Is Diagnosed
  5. Splinting
  6. Corticosteroid Injection
  7. Diabetes and Injection Results
  8. Release Surgery: Open and Percutaneous
  9. Complications After Surgery
  10. Trigger Thumb and Trigger Finger in Children
  11. What Is Not Known
  12. Key Research Papers
  13. Connections
  14. Featured Videos

What Happens Inside the Finger

Each finger is bent by long flexor tendons that run from the forearm muscles to the finger bones. Along the way the tendons slide through a tunnel, the tendon sheath, which is held against the bone by a series of tough bands called pulleys. The A1 pulley is the first of these, lying in the palm just below the crease at the base of the finger. In trigger finger the tendon can no longer glide smoothly through it.

A Cochrane review describes the core problem as a mismatch between the diameter of the flexor tendons and the A1 pulley. A second Cochrane review describes the gliding of the tendon through the A1 pulley as impaired by degeneration, inflammation and swelling.

The pulley changes its tissue type. In a 1991 study, Sampson and colleagues examined 89 A1 pulleys removed from 65 people with trigger digits and compared them with 20 control pulleys taken from cadavers. In both groups the pulley had two layers: an outer layer with blood vessels and an inner layer against which the tendon glides. That inner layer already looked partly like fibrocartilage, the tough, gristly tissue found in places such as the knee meniscus. In trigger digits, the number of cartilage-type cells (chondrocytes) and the surrounding matrix was significantly increased. The researchers found no lining of synovial cells on the pulley surface in either group, and they described the mechanism of triggering as a fibrocartilage metaplasia, meaning that the gliding layer turns into more cartilage-like tissue.

The tendon thickens too. Ultrasound studies show that the problem is not confined to the pulley. Sato and colleagues measured 67 trigger digits and found that the thickness of the flexor tendon under the A1 pulley was proportional to the severity of triggering. In fingers other than the thumb, the tendon was already thicker before any triggering began; in the thumb, the tendon and the A1 pulley thickened significantly only after triggering appeared. A study of 20 patients (31 fingers) found that the next pulley along, the A2 pulley, and the tendon beneath it were also thickened, and that this thickening was related to clinical grade.

A 2019 review by Brozovich and colleagues summarises the picture as abnormal thickening, scarring and inflammation of both the A1 pulley and the flexor tendon, with tissue changes that correlate well with clinical severity. Its authors also note that corticosteroid injections decrease the thickness of the A1 pulley.

Symptoms and the Severity Grades

An ultrasound review by Bianchi and colleagues describes the key clinical finding as a brief blockage of the digit when it is bent, followed by a painful snap when it is straightened. People often describe a click, a catch, or a finger that stays bent and has to be pushed straight with the other hand. A tender lump (nodule) may be felt in the palm over the A1 pulley. The Dupuytren's contracture page explains how this differs from the cord and fixed bend of Dupuytren's disease.

The Quinnell grade. Researchers grade severity with scales such as the Quinnell grade. As set out by Kozin and colleagues, it runs from 0 to 4:

These grades appear throughout the research: the night-splint study described below enrolled only people with Quinnell grade 1 or 2 symptoms of less than 3 months, and a large study of children found that a higher Quinnell grade at presentation went with a greater chance of surgery. Sato and colleagues used their own four-group scale and found that the A1 pulley was thickest, and the volar plate of the joint significantly thickened, in the group with continuous triggering that was easily reduced by active straightening (their grade III).

In a study of 139 people having surgery, Holm and colleagues found that a low range of motion before the operation did not affect the result one year later, whereas a high level of pain before surgery was strongly associated with a poor outcome.

How Common It Is and Who Gets It

The largest recent count. Sun and colleagues searched a large health-record research network for people diagnosed with trigger finger between 2015 and 2023 and found 465,763 patients. They report a prevalence of 2.0% in the general population and 5.8% in people with diabetes. People with trigger finger were older than those without it (average age 60.6 against 39.5 years) and more often female (63.0% against 54.3%). The most affected digits were the thumb (35.2%), the middle finger (34.1%) and the ring finger (26.0%). After adjusting for demographic differences, the trigger finger group had nearly four times the prevalence of carpal tunnel syndrome.

Other estimates. A 2024 scoping review by Shohda and Sheta gives a prevalence of greater than 3% in the general population and states that this can rise to between 5% and 20% in people with diabetes. Hollins and colleagues cite a general-population prevalence of 2 percent.

Diabetes. The 2019 review by Brozovich and colleagues describes people with diabetes as the most at-risk population, consistent with the higher prevalence in the Sun data. The link is not found in every sample: a small 7-week study of 46 patients with 54 trigger fingers at one clinic, by Shah and Rettig, observed no strong association between trigger finger and diabetes or hypothyroidism. That study found the ring finger, thumb and long (middle) finger to be the most frequently affected. More on diabetes and treatment results is in the diabetes section below and on the Diabetes page.

Other conditions reported alongside it. The surgical study by Holm and colleagues describes trigger finger as associated with diabetes, rheumatic disease and carpal tunnel syndrome, and carpal tunnel syndrome was the most common other condition in its cohort. In the same study, psoriatic arthritis and atopic disease (allergic conditions such as eczema and asthma) were linked with a poorer result after surgery.

Amyloidosis. Amyloidosis is a group of diseases in which misfolded proteins build up in tissues, including the heart. In a study of United States veterans, Sood and Lipira followed 126,788 people who had trigger release surgery, carpal tunnel release or both, along with matched controls. Amyloidosis was diagnosed in 52 of 26,757 people who had trigger release alone, at a median of 4.7 years after surgery, a 10-year cumulative incidence of 0.26%, against 0.053% in the controls. After adjustment, trigger release alone was linked with a higher risk of amyloidosis (adjusted subdistribution hazard ratio 4.80) and of heart failure (1.91), but not of death. Among people who had trigger release, age, Black race, earlier carpal tunnel release, heart failure and the number of digits released were independent risk factors for amyloidosis. The study shows an association; it does not show that trigger finger causes amyloidosis. The Cardiac Amyloidosis page covers the heart form.

How It Is Diagnosed

Trigger finger is usually diagnosed from the history and an examination of the hand: the catching or locking, the point of tenderness over the A1 pulley, and sometimes a palpable nodule. Sato and colleagues note that most clinicians can easily determine the severity of a trigger digit by clinical examination.

Ultrasound. Ultrasound is the imaging method these reviews describe. Bianchi and colleagues write that ultrasound allows an accurate static and moving (dynamic) evaluation of the finger, together with a comparison against the neighbouring normal fingers, and they describe it as the radiologic method of first choice. In their view, imaging helps establish severity, identify an underlying cause and guide management. Sato and colleagues add that ultrasound can show the thickness of the flexor tendon and A1 pulley, and that measuring the A1 pulley might help judge how the condition progresses.

Conditions that resemble it. In young children, trigger thumb is often mistaken for something else: a 2026 review by Gordon and Sherman states that misdiagnosis as a fracture or dislocation is common. In adults, the Dupuytren's contracture page describes how that condition produces a palpable cord and a fixed bend rather than a snap.

Splinting

A splint (orthosis) keeps the affected finger still; the splinting review below describes this as reducing pain and improving function.

Systematic review. McKenna and colleagues reviewed 13 studies of blocking splints worn for 6 to 12 weeks. Splinting consistently reduced pain, stopped triggering and improved function in the short term (within 1 year), with success rates up to 97%. Across splint types, splinting was most effective when worn 24 hours a day. A splint that blocks the middle knuckle joint (the proximal interphalangeal joint) gave more effective pain reduction and better function than one that blocks the knuckle at the base of the finger (the metacarpophalangeal joint), and patients found it more comfortable and wore it longer. The review notes that adherence can be challenging and that long-term results have not been studied well.

Night splinting. In a study by Drijkoningen and colleagues, 34 adults with Quinnell grade 1 or 2 trigger digits of less than 3 months wore a custom night splint for at least 6 weeks. Triggering resolved completely in 18 patients (55%). Sixteen did not resolve and went on to a steroid injection.

Splint against injection. A randomised trial at a university hospital, by Atthakomol and colleagues assigned 120 adults to a splint alone (43), a steroid injection alone (40) or both (37). The splint held the base knuckle in a neutral position for at least 8 hours a day for 6 weeks; the injection was triamcinolone acetonide with lidocaine into the tendon sheath. There were no clinically important differences in pain or hand function among the three groups at 6, 12 or 52 weeks. The authors concluded that combining the two gave no added benefit over either alone.

Corticosteroid Injection

A corticosteroid is an anti-inflammatory steroid medicine. For trigger finger it is injected, usually with a local anaesthetic, into or next to the tendon sheath at the A1 pulley.

The first Cochrane review. In 2009, a Cochrane review by Peters-Veluthamaningal and colleagues found only two small randomised trials, with 63 participants. A corticosteroid injection with lidocaine was more effective than lidocaine alone for treatment success at four weeks (relative risk 3.15), with a number needed to treat of 3: on average, three people had to be injected for one extra success. In one of the trials the effect lasted up to four months. No side effects were reported. The reviewers rated both trials as poor in method.

Which steroid. A 2026 systematic review by Kuper and colleagues analysed 13 randomised trials with 1116 patients (1153 digits). Methylprednisolone showed higher overall remission (83.6%) than triamcinolone (44.8%). Higher triamcinolone doses improved results, but no statistically significant dose-response relationship was found. Ultrasound-guided and unguided injections did not differ significantly, nor did injections into the sheath and outside it. Second injections improved results in people who had only partly responded. Adverse events, such as thinning of the skin and a painful steroid flare, occurred in 2.8% of triamcinolone patients and were not reported for methylprednisolone. The review also found that add-on treatments such as splinting had limited effect on the outcome.

How often a single injection works in everyday practice. In a review of 297 patients at one institution, Hollins and colleagues found that steroid injection alone was successful in 65 percent, with an average of 1.61 injections per patient. Symptoms lasting longer than 2.5 months went with a higher failure rate (40.4 percent against 29.5 percent), as did other disease in the same hand (43.4 percent against 30.8 percent).

Recurrence and repeat treatment. In the large records study by Sun and colleagues, among patients who had a first injection, 25.9% received another injection within 1 year and 36.0% within 3 years, while 13.4% and 20.1% went on to surgery within 1 and 3 years.

Long-term results. Wojahn and colleagues followed 366 first-time injections for at least five years. Forty-five percent of patients had long-term success after a single injection, meaning no further injection or surgery for that digit. Ten-year success was 56% for women with their first trigger finger, against 35% for men with their first trigger finger, 39% for women with several trigger fingers and 37% for men with several. Eighty-four percent of the failures occurred within the first two years, and the authors note that people who are still symptom-free two years after injection are likely to stay that way. Age, symptom type and diabetes status (not divided by severity) did not predict success. A smaller series of 71 digits, by Castellanos and colleagues, followed for a median of 8 years, found complete remission in 69%; the success rate was 81% in thumbs against 56% in other digits, and no complications were found.

Injected anti-inflammatory painkillers instead of steroid. A 2021 Cochrane review by Leow and colleagues looked at two trials (231 adults) comparing a single injection of a non-steroidal anti-inflammatory drug (NSAID), diclofenac or ketorolac, with a steroid injection. There may be little to no difference in resolution of symptoms at 12 to 24 weeks (34% with the non-steroidal anti-inflammatory drug, 41% with the steroid), while persistent moderate to severe symptoms may be more common with the non-steroidal anti-inflammatory drug (28% against 14%). The evidence was rated low to very low certainty.

Diabetes and Injection Results

Several studies report that steroid injections work less well in people with diabetes.

The 2019 Brozovich review describes corticosteroids as only moderately effective, especially for people with diabetes. In the long-term Wojahn series, by contrast, diabetes status as a single yes-or-no factor did not predict success.

Release Surgery: Open and Percutaneous

Surgery cuts the A1 pulley so the tendon can glide freely. In open release, the surgeon makes a small cut in the palm and divides the pulley under direct view. In percutaneous release, the pulley is divided through the skin with a needle or small blade, sometimes guided by ultrasound. In the Sun records study, 13.5% of people with trigger finger had surgical release within 1 year and 16.6% within 3 years.

Surgery against injection. The 2018 Cochrane review by Fiorini and colleagues included 14 trials with 1260 participants and 1361 trigger fingers; about 70% of participants were women. Most studies had significant flaws in method. In two trials (270 participants) followed from six to 12 months, triggering came back in 50 of 130 people after steroid injection and in 8 of 140 after open surgery (risk ratio 0.17). Open surgery was more painful at first: at one week, 38 of 56 people had pain in the palm after open surgery against 9 of 49 after injection. The reviewers were uncertain whether open surgery improved overall resolution, or whether it changed the risk of adverse events such as infection, tendon injury and nerve or blood-vessel injury, because few events occurred. Hand function and satisfaction were not reported. The evidence was rated low to very low quality.

Open against percutaneous. A 2026 meta-analysis by Huang and colleagues combined 14 randomised trials with 996 patients. Percutaneous release gave better arm-and-hand function scores at one week, under one month and at three months, a faster return to work (by 12.82 days on average) and a shorter need for painkillers after the operation (by 4.66 days). There were no significant differences in longer-term outcomes, including function scores, grip strength, motion, complications or revision rates. The authors concluded that both methods are effective.

An older view differs. The 2019 Brozovich review states that the open approach carries a greater short-term risk of infection and scar tissue but gives a better long-term outcome than the percutaneous approach. The later meta-analysis did not find a long-term difference. The same review, looking at cost, concluded that for women without diabetes with a single trigger thumb, two steroid injections before percutaneous release was the most cost-effective route, and that immediate percutaneous release was most cost-effective for all other groups.

Complications After Surgery

Trigger finger release is widely thought of as a safe, low-risk procedure, as both studies below note in their introductions. When they counted every documented problem, they found more complications than that reputation suggests.

Trigger Thumb and Trigger Finger in Children

Trigger thumb in young children is a different condition from adult trigger finger. Baek and colleagues describe it as a bending deformity at the thumb's end joint (the interphalangeal joint), and Gordon and Sherman describe a nodule on the palm side of the thumb as part of the diagnosis. Gordon and Sherman describe it as a developmental condition that accounts for 1 in 2000 visits to the pediatric hand clinic, and note that certain congenital malformations occur at a higher rate in children with trigger thumbs.

Many resolve on their own.

Trigger finger (not thumb) in children. Kozin and colleagues describe pediatric trigger finger as 10 times less common than trigger thumb. In a three-hospital study of 321 children with 449 trigger fingers, Jia and colleagues found that symptoms began at a mean age of 5.4 years and that the middle finger was most often affected (34.7%). Surgery gave complete resolution in 97.1%, against 30.0% without surgery, and splinting did not improve resolution in children treated without surgery. Jia and colleagues call it anatomically complex. Kozin and colleagues explain that releasing the A1 pulley alone may not stop the triggering in children, and that part of one of the tendons (a slip of the flexor digitorum superficialis) may also need to be removed.

What Is Not Known

Decisions about splints, injections or surgery belong with a clinician who can examine the hand.

Key Research Papers

  1. Sampson SP, Badalamente MA, Hurst LC, Seidman J. Pathobiology of the human A1 pulley in trigger finger. J Hand Surg Am. 1991;16(4):714-21. PubMed PMID: 1880372
  2. Sato J, Ishii Y, Noguchi H, Takeda M. Sonographic appearance of the flexor tendon, volar plate, and A1 pulley with respect to the severity of trigger finger. J Hand Surg Am. 2012;37(10):2012-20. PubMed PMID: 22939830
  3. Kim SJ, Lee CH, Choi WS, Lee BG, Kim JH, Lee KH. The thickness of the A2 pulley and the flexor tendon are related to the severity of trigger finger: results of a prospective study using high-resolution ultrasonography. J Hand Surg Eur Vol. 2016;41(2):204-11. PubMed PMID: 26568540
  4. Bianchi S, Gitto S, Draghi F. Ultrasound Features of Trigger Finger: Review of the Literature. J Ultrasound Med. 2019;38(12):3141-3154. PubMed PMID: 31106876
  5. Brozovich N, Agrawal D, Reddy G. A Critical Appraisal of Adult Trigger Finger: Pathophysiology, Treatment, and Future Outlook. Plast Reconstr Surg Glob Open. 2019;7(8):e2360. PubMed PMID: 31592381
  6. Kozin SH, Park E, Zlotolow DA. Surgery for Pediatric Trigger Finger. JBJS Essent Surg Tech. 2024;14(4):e23.00064. PubMed PMID: 39525330
  7. Sun C, Campbell H, Demetriou Z, Castro A, Jones CM, Ilyas AM. Epidemiology, Treatment Patterns, and Comorbidities of Trigger Finger: A Contemporary Population-Based Analysis. J Am Acad Orthop Surg. 2026;34(15):e2148-e2153. PubMed PMID: 42357875
  8. Shohda E, Sheta RA. Misconceptions about trigger finger: a scoping review. Definition, pathophysiology, site of lesion, etiology. Trigger finger solving a maze. Adv Rheumatol. 2024;64(1):53. PubMed PMID: 38992697
  9. Shah A, Rettig M. Trigger Finger Location and Association of Comorbidities. Bull Hosp Jt Dis (2013). 2017;75(3):198-200. PubMed PMID: 28902605
  10. Sood RF, Lipira AB. Risk of Amyloidosis and Heart Failure Among Patients Undergoing Surgery for Trigger Digit or Carpal Tunnel Syndrome: A Nationwide Cohort Study With Implications for Screening. J Hand Surg Am. 2022;47(6):517-525.e4. PubMed PMID: 35346527
  11. McKenna ES, Co N, Brancaccio H, Soper B, Borole A, Han Y, Kirschenbaum D, Katt BM. Efficacy of Splinting in Managing Adult Trigger Finger: A Systematic Review of Short-Term Outcomes. J Hand Surg Glob Online. 2026;8(1):100881. PubMed PMID: 41362294
  12. Drijkoningen T, van Berckel M, Becker SJE, Ring DC, Mudgal CS. Night Splinting for Idiopathic Trigger Digits. Hand (N Y). 2018;13(5):558-562. PubMed PMID: 28825334
  13. Atthakomol P, Wangtrakunchai V, Chanthana P, Phinyo P, Manosroi W. Are There Differences in Pain Reduction and Functional Improvement Among Splint Alone, Steroid Alone, and Combination for the Treatment of Adults With Trigger Finger? Clin Orthop Relat Res. 2023;481(11):2281-2294. PubMed PMID: 37083487
  14. Peters-Veluthamaningal C, van der Windt DA, Winters JC, Meyboom-de Jong B. Corticosteroid injection for trigger finger in adults. Cochrane Database Syst Rev. 2009;2009(1):CD005617. PubMed PMID: 19160256
  15. Kuper G, Da Silva D, Carr M, Brown E. Comparative effectiveness of corticosteroid injections for trigger finger: A systematic review of randomized controlled trials. J Plast Reconstr Aesthet Surg. 2026;113:332-341. PubMed PMID: 41352303
  16. Hollins AW, Hein R, Atia A, Taskindoust M, Darner G, Shammas R, Mithani SK. Symptom Duration and Diabetic Control Influence Success of Steroid Injection in Trigger Finger. Plast Reconstr Surg. 2022;150(2):357e-363e. PubMed PMID: 35671444
  17. Wojahn RD, Foeger NC, Gelberman RH, Calfee RP. Long-term outcomes following a single corticosteroid injection for trigger finger. J Bone Joint Surg Am. 2014;96(22):1849-54. PubMed PMID: 25410501
  18. Castellanos J, Muñoz-Mahamud E, Domínguez E, Del Amo P, Izquierdo O, Fillat P. Long-term effectiveness of corticosteroid injections for trigger finger and thumb. J Hand Surg Am. 2015;40(1):121-6. PubMed PMID: 25443167
  19. Leow MQH, Zheng Q, Shi L, Tay SC, Chan ES. Non-steroidal anti-inflammatory drugs (NSAIDs) for trigger finger. Cochrane Database Syst Rev. 2021;4(4):CD012789. PubMed PMID: 33849080
  20. Baumgarten KM, Gerlach D, Boyer MI. Corticosteroid injection in diabetic patients with trigger finger. A prospective, randomized, controlled double-blinded study. J Bone Joint Surg Am. 2007;89(12):2604-11. PubMed PMID: 18056491
  21. Wang AA, Hutchinson DT. The effect of corticosteroid injection for trigger finger on blood glucose level in diabetic patients. J Hand Surg Am. 2006;31(6):979-81. PubMed PMID: 16843159
  22. Fiorini HJ, Tamaoki MJ, Lenza M, Gomes Dos Santos JB, Faloppa F, Belloti JC. Surgery for trigger finger. Cochrane Database Syst Rev. 2018;2(2):CD009860. PubMed PMID: 29460276
  23. Huang KC, Chu YY, Lin YT, Wang MJ, Lee CH. Comparative effectiveness of open versus percutaneous release for trigger fingers: A systematic review and meta-analysis of randomized controlled trials. J Orthop Sci. 2026;31(4):789-798. PubMed PMID: 41571568
  24. Koopman JE, Hundepool CA, Duraku LS, Smit JM, Zuidam JM, Selles RW, Wouters RM, Hand-Wrist Study Group. Complications and Functional Outcomes following Trigger Finger Release: A Cohort Study of 1879 Patients. Plast Reconstr Surg. 2022;150(5):1015-1024. PubMed PMID: 35994343
  25. Will R, Lubahn J. Complications of open trigger finger release. J Hand Surg Am. 2010;35(4):594-6. PubMed PMID: 20189319
  26. Holm B, Rönnelid J, Baecklund E, Wiig M. Trigger finger - Poor outcome of surgery associated with younger age, pain, psoriatic arthritis and atopic disease. Ups J Med Sci. 2024;129. PubMed PMID: 39376589
  27. Gordon D, Sherman PJ. Pediatric trigger thumb: clinical management update. Curr Opin Pediatr. 2026;38(2):212-218. PubMed PMID: 41670430
  28. Tang Q, Miao X, Zhao K, Hu J, Ren X. The prevalence of spontaneous resolution among pediatric trigger thumb: a systematic review and meta-analysis. J Orthop Surg Res. 2024;19(1):461. PubMed PMID: 39095911
  29. Baek GH, Kim JH, Chung MS, Kang SB, Lee YH, Gong HS. The natural history of pediatric trigger thumb. J Bone Joint Surg Am. 2008;90(5):980-5. PubMed PMID: 18451388
  30. Hutchinson DT, Rane AA, Montanez A. The Natural History of Pediatric Trigger Thumb in the United States. J Hand Surg Am. 2021;46(5):424.e1-424.e7. PubMed PMID: 33436280
  31. Jia L, King JD, Goubeaux C, Belardo ZE, Little KJ, Samora JB, Marks J, Shah AS. Presentation and Management of the Pediatric Trigger Finger: A Multicenter Retrospective Cohort Study. J Hand Surg Am. 2023;48(7):665-672. PubMed PMID: 37256247

PubMed Topic Searches

  1. Trigger finger and A1 pulley pathology
  2. Corticosteroid injection for trigger finger: randomised trials
  3. Splinting for trigger finger
  4. Percutaneous against open trigger finger release
  5. Trigger finger and diabetes
  6. Pediatric trigger thumb natural history

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