ClinicalTrials.gg
RecruitingNCT06476977Updated Aug 19, 2024

Intrasynovial Digital Anesthesia in Trigger Finger

An interventional study of Dorsal webspace combined corticosteroid and anesthetic injection and Palmar combined corticosteroid and anesthetic injection in Trigger Finger Disorder, sponsored by Kevin Zuo. Recruiting at 1 site in Canada. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2024-08-19.

Sponsored by Kevin Zuo · Not applicable, Interventional, and Treatment

From the registry’s dates

  • Primary completion was expected by Feb 2026, 9 months ago, but the record still lists the study as recruiting.
  • Started Jul 2024; still recruiting 2 years 4 months later.
Phase
Not applicable
Study type
Interventional
Enrollment
60
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

Trigger finger is a common disease of the hand involving swelling and inflammation of the tendon which flexes a finger, causing catching, locking, and/or pain. Trigger finger is typically treated by hand surgeons with a steroid injection through the front/palm side of the hand into the area near the tendon (i.e., at the base of the affected finger). This steroid injection is often combined with a local anesthetic (numbing agent) to help reduce short-term pain from the injection. However, the front/palm side of the hand is known to be very sensitive, and the steroid injection can be quite painful as the needle pierces the front/palm skin.

To reduce the pain of steroid injections for trigger finger, a different approach involves performing the injection from the back/dorsal side of the hand, which is thought to be less sensitive (and therefore less painful) than the front/palm side of the hand. This technique is sometimes used and has been previously studied, but it is not clear if it can offer less injection-related pain than standard treatment.

Accordingly, this study will be comparing short-term injection-associated pain between front/palm side and back/dorsal side steroid injections for trigger finger. The study will also seek to understand what area of the hand is numbed by the anesthetic when doing a front/palm side injection versus a back/dorsal side injection of the hand. Overall, the investigators hypothesize that back/dorsal side injections will be less painful than front/palm side injections for trigger fingers and that the area of numbing from the anesthetic will be equivalent between both types of injections.

Read the detailed description

Trigger finger (stenosing tenosynovitis) is one of the most common pathologies assessed by hand surgeons in clinic. Trigger finger involves inflammation or edema of the flexor tendon causing friction of the tendon at the site of the A1 annular pulley located at the base of the affected finger in the palm. Trigger finger is typically managed non-surgically in a clinic setting with percutaneous corticosteroid injection (CSI) which can be successful in alleviating symptoms. Patients with trigger finger who do not respond to CSI, have incomplete relief, and/or who have recurrent symptoms may then receive surgical management with release of the A1 pulley.

CSIs for trigger fingers are among the most common procedures performed by hand surgeons and are often administered multiple times in a single clinic day. CSIs are frequently mixed 50:50 with 1% lidocaine to provide post-injection analgesia for patients as well as symptomatic relief of the trigger finger if acutely inflamed. These injections are commonly administered from a palmar approach into the A1 pulley of the affected digit. Numerous technical variations of palmar trigger finger injections have been described involving either subcutaneous injection superficial to the flexor tendon sheath or intrasynovial (transthecal) injection into the flexor tendon sheath.

Unfortunately, given the rich sensory innervation of the palmar skin, palmar injections are associated with significant pain as the needle pierces the skin. An alternative technique is to provide digital anesthesia from a dorsal webspace approach, injecting the local anesthetic into the flexor tendon synovial sheath. This intrasynovial or transthecal technique has the benefit of a dorsal approach where the skin is less sensitive resulting in less pain (6). This technique has been described previously but is not familiar to many hand surgeons and is not routinely used in North America.

Anecdotally, patients report significantly decreased pain with the dorsal intrasynovial injection technique for trigger finger injections, but pain scores have not been quantitatively evaluated or compared to the pain scores of traditional palmar trigger finger injections. Furthermore, it is not known what distribution of digital sensory blockade is achieved with this intrasynovial technique, particularly on the dorsal surface of the digit which is discontinuous with the flexor tendon sheath and innervated by the sensory branch of the radial nerve.

Accordingly, it is hypothesized that injecting corticosteroids into the synovial sheath of the flexor tendon will result in less pain over 24 hours if performed through the dorsal webspace versus the palmar side of the affected digit.

02

Conditions studied

  • Trigger Finger Disorder

Keywords

  • trigger finger
  • stenosing tenosynovitis
  • corticosteroid injection
  • palmar
  • dorsal
  • pain
03

In context

Trigger Finger Disorder

93 studies on the registry are indexed under Trigger Finger Disorder; 22 are open to participants now.

This study's planned enrollment of 60 is close to the median of 66 across 75 interventional studies indexed under Trigger Finger Disorder.

Browse Trigger Finger Disorder studies →

Lead sponsor

This is the only study on the registry with Kevin Zuo as lead sponsor.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Be 18 years of age or older
  • Have a diagnosis of trigger finger (can be any of the 5 digits)
  • Opting to receive a CSI for their triggering finger

Exclusion criteria

Exclusion Criteria:

  • Decline to obtain a CSI for trigger finger management
  • Receiving multiple CSI for trigger finger management at the appointment
  • Past CSI and/or surgery to the digit involved
  • Unable to communicate in English
05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
60 participants (estimated)

Study arms

  • Experimental
    Dorsal Webspace Approach

    A dorsal approach involves passing the needle with a 1:1 triamcinolone and lidocaine mixture in the dorsal webspace skin aiming just palmar to the proximal phalanx bone such that the needle is directed into the flexor tendon sheath at the A1 annular pulley.

    Procedure: Dorsal webspace combined corticosteroid and anesthetic injection

  • Active comparator
    Palmar Approach

    Standard approach for injecting the 1:1 triamcinolone and lidocaine mixture involves the needle passing through the cutaneous and subcutaneous layers of the palmar skin surface and into the flexor tendon sheath at the A1 annular pulley.

    Procedure: Palmar combined corticosteroid and anesthetic injection

Interventions

  • ProcedureDorsal webspace combined corticosteroid and anesthetic injection

    The dorsal webspace injection consists of a 1cc mixture of 0.5cc triamcinolone (Kenalog) 10mg/mL and 0.5cc 1% lidocaine for analgesic purposes.

  • ProcedurePalmar combined corticosteroid and anesthetic injection

    The palmar injection consists of a 1cc mixture of 0.5cc triamcinolone (Kenalog) 10mg/mL and 0.5cc 1% lidocaine for analgesic purposes.

06

What researchers measure

Primary outcomes

  1. Visual Analogue Scale (VAS) - Pain

    100mm mechanical rating scale for pain, ranging from 0mm ("no pain") to 100mm ("pain as bad as it could be"); higher scores indicate a worse outcome.

    Time frame: measured at 0 hours, 4 hours, and 24 hours post-injection

  2. Numerical Rating Scale (NRS) - Pain

    11-point numerical rating scale for pain, ranging from 0 (no pain) to 10 (worst pain ever possible); higher scores indicate a worse outcome.

    Time frame: measured at 0 hours, 4 hours, and 24 hours post-injection

  3. Short-Form McGill Pain Questionnaire (SFMPQ) - Present Pain Intensity (PPI)

    5-point combined numerical-word rating scale for pain, ranging from 1 (mild) to 5 (excruciating); higher scores indicate a worse outcome.

    Time frame: measured at 0 hours, 4 hours, and 24 hours post-injection

Secondary outcomes

  1. Sensory Assessment - Light Touch

    Semmes-Weinstein 2.0g monofilament test as threshold of sensory impairment

    Time frame: measured at 0 hours post-injection

  2. Sensory Assessment - Pain

    Pinprick pain sensation with an 18-gauge sharp needle tip

    Time frame: measured at 0 hours post-injection

07

Study locations

1 of 1 sites recruiting
  • University Health Network - Toronto Western Hospital
    Toronto, Ontario M5T 2S8, Canada
    Recruiting
    • Kevin Zuo, MD, MASc · Contactkevin.zuo@uhn.ca · 416-603-5802
    • Kevin Zuo, MD, MASc · Principal investigator
08

References and documents

Publications

  • Akhtar S, Bradley MJ, Quinton DN, Burke FD. Management and referral for trigger finger/thumb. BMJ. 2005 Jul 2;331(7507):30-3. doi: 10.1136/bmj.331.7507.30. No abstract available. PubMed 15994689 ↗
  • Makkouk AH, Oetgen ME, Swigart CR, Dodds SD. Trigger finger: etiology, evaluation, and treatment. Curr Rev Musculoskelet Med. 2008 Jun;1(2):92-6. doi: 10.1007/s12178-007-9012-1. PubMed 19468879 ↗
  • Fleisch SB, Spindler KP, Lee DH. Corticosteroid injections in the treatment of trigger finger: a level I and II systematic review. J Am Acad Orthop Surg. 2007 Mar;15(3):166-71. doi: 10.5435/00124635-200703000-00006. PubMed 17341673 ↗
  • Merry SP, O'Grady JS, Boswell CL. Trigger Finger? Just Shoot! J Prim Care Community Health. 2020 Jan-Dec;11:2150132720943345. doi: 10.1177/2150132720943345. PubMed 32686570 ↗
  • Patrinely JR Jr, Johnson SP, Drolet BC. Trigger Finger Corticosteroid Injection With and Without Local Anesthetic: A Randomized, Double-Blind Controlled Trial. Hand (N Y). 2021 Sep;16(5):619-623. doi: 10.1177/1558944719884663. Epub 2019 Nov 5. PubMed 31690121 ↗
  • Jimenez I, Garces GL, Marcos-Garcia A, Medina J. A randomized controlled trial of dorsal web space versus palmar midline injection of steroid in the treatment of trigger digits. J Hand Surg Eur Vol. 2020 Dec;45(10):1071-1077. doi: 10.1177/1753193420927999. Epub 2020 Jun 3. PubMed 32493111 ↗
  • Bitar H, Zachrisson AK, Bystrom M, Stromberg J. Day-by-day symptom relief after corticosteroid injection for trigger digit: a randomized controlled study of two techniques. J Hand Surg Eur Vol. 2023 Oct;48(9):849-856. doi: 10.1177/17531934231177422. Epub 2023 May 22. PubMed 37218106 ↗
  • Rosenbaum YA, Benvenuti N, Yang J, Ruff ME, Awan HM, Samora JB. The Effect of Trigger Finger Injection Site on Injection-Related Pain. Hand (N Y). 2018 Mar;13(2):164-169. doi: 10.1177/1558944717703134. Epub 2017 Apr 26. PubMed 28443675 ↗
  • Mathew A. Mid-axial injection of steroid into the flexor sheath for trigger fingers. J Hand Microsurg. 2014 Jun;6(1):49-52. doi: 10.1007/s12593-014-0120-z. Epub 2014 Feb 21. No abstract available. PubMed 24876694 ↗
  • Jimenez I, Medina J, Marcos-Garcia A, Garces GL. Out-of-sheath corticosteroid injections through the dorsal webspace for trigger finger and trigger thumb. A prospective cohort study. Rev Esp Cir Ortop Traumatol. 2022 Jul-Aug;66(4):260-266. doi: 10.1016/j.recot.2021.03.009. Epub 2021 Aug 6. English, Spanish. PubMed 34366261 ↗
  • Haefeli M, Elfering A. Pain assessment. Eur Spine J. 2006 Jan;15 Suppl 1(Suppl 1):S17-24. doi: 10.1007/s00586-005-1044-x. Epub 2005 Dec 1. PubMed 16320034 ↗
  • Melzack R. The McGill Pain Questionnaire: major properties and scoring methods. Pain. 1975 Sep;1(3):277-299. doi: 10.1016/0304-3959(75)90044-5. PubMed 1235985 ↗
09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Started Jul 2024 (actual). Primary completion is estimated for Feb 2026, 19 months after the start.

Of 34 interventional studies with no phase under Trigger Finger Disorder, half reached primary completion within 21 months of starting (the median), counting those still running; a quarter within 7 and three quarters within 41. This study's planned 19 months is close to that.

How these figures are worked out, and which studies are left out of them.

Registered
Jun 20, 2024
First posted
Jun 27, 2024
StartActual
Jul 3, 2024
Primary completionEst.
Feb 2026
CompletionEst.
Jul 2026
Last update
Aug 19, 2024
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Aug 19, 2024, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06476977
Lead sponsor
Kevin Zuo
Responsible party
Kevin Zuo (Staff Surgeon, Plastic and Reconstructive Surgery, University Health Network, Toronto) — Sponsor-investigator
First posted
Jun 27, 2024
Start date
Jul 3, 2024
Primary completion
Feb 2026 (estimated)
Completion
Jul 2026 (estimated)
Last update
Aug 19, 2024

Study contacts

Kevin Zuo, MD, MASc
Contact
kevin.zuo@uhn.ca
416-603-5802
Daniel Antflek, BSc
Contact
daniel.antflek@uhn.ca
416-603-5800 ext. 6133
Kevin Zuo, MD, MASc
principal investigator · University Health Network, Toronto

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion