Surgery for trigger finger

Background

Trigger finger is clinically characterised by pain and catching during finger movements. Classically, the initial treatment is non-surgical using nonsteroidal anti-inflammatory drugs, splinting and corticosteroid injection, and may require surgical treatment if the conventional treatment fails. Although it is a common condition, there is no consensus about the best surgical treatment approach (by skin incision and direct vision of the hand structures (open); approaches via needle or blade introduced through the skin, with no direct vision of the hand structures (percutaneous); or via a flexible tube with a light camera attached to it (endoscopic).

Study characteristics

This Cochrane Review is current to August 2017. We included 14 randomised controlled trials involving 1260 participants, totalling 1361 trigger fingers. Two studies compared open surgery versus steroid injections, five studies compared percutaneous surgery versus steroid injection, one study compared open surgery versus steroid injection plus hyaluronic acid injection, one study compared percutaneous surgery plus steroid injection versus steroid injection, five studies compared percutaneous surgery versus open surgery, one study compared endoscopic surgery versus open surgery and one study compared three types of skin incision to open surgery. The majority of participants were female (about 70%); they were aged between 16 and 88 years; and the mean follow-up of participants after the procedure was eight weeks to 23 months. Due to space constraints, the reporting of all results was limited to the main comparison — open surgery versus steroid injection — because open surgery is the oldest and the most widely used treatment method and considered as standard surgery, whereas steroid injection is the least invasive control treatment method as reported in the studies in this review and is often used as first-line treatment in clinical practice.

Key results

Based on two trial (270 participants), compared with the steroid injection procedure:

Resolution of trigger finger (lessening of symptoms with no recurrence):

• 92 out of 100 people had resolution of symptoms with open surgery.

• 61 out of 100 people had resolution of symptoms with steroid injection.

Incidence of pain, assessed as the presence or absence of pain after the procedure was performed (at one week):

• 49% more people had pain with open surgery (33% to 66% more).

• 68 out of 100 people had pain with open surgery.

• 19 out of 100 people had pain with steroid injection.

Recurrence of the trigger finger (from six to 12 months):

• 29% fewer people had recurrence of symptoms with open surgery (60% fewer to 3% more).

• 7 out of 100 people had recurrence of symptoms with open surgery.

• 39 out of 100 people had recurrence of symptoms with steroid injection.

Adverse events:

Adverse events including infections, tendon injuries, cutaneous discomfort, flare or fat necrosis at the procedure site, or neovascular events were uncommon in either treatment group.

No study reported hand function or participant-reported treatment success or satisfaction.

Quality of the evidence

Very low quality evidence from two trials means we are uncertain whether open surgery improve resolution of trigger finger in comparison with steroid injection, due the risk of bias in the design of the studies, inconsistencies between studies and the small number of participants in studies. Low-quality evidence from two trials shows that open surgery may result in fewer recurrences of trigger finger compared with steroid injection procedure, although it increases the incidence of pain during the first week after the procedure. Evidence was downgraded to 'low' due to the risk of bias in the design and the small number of participants. No studies measured functional improvement or participant satisfaction in the comparison between open surgery and steroid injection. We are uncertain whether there is a difference in the risk of adverse events or neurovascular injury between treatments, as few events occurred in the studies.

Only low and very low-quality evidence was found for other comparisons so we are uncertain if percutaneous surgery has any benefits over steroid injection, or if open surgery is better than steroid plus hyaluronic acid, or if one type of surgery is better than another.

Authors' conclusions: 

Low-quality evidence indicates that, compared with steroid injection, open surgical treatment in people with trigger finger, may result in a less recurrence rate from six up to 12 months following the treatment, although it increases the incidence of pain during the first follow-up week. We are uncertain about the effect of open surgery with regard to the resolution rate in follow-up at six to 12 months, compared with steroid injections, due high heterogeneity and few events occurred in the trials; we are uncertain too about the risk of adverse events and neurovascular injury because of a few events occurred in the studies. Hand function or participant satisfaction were not reported.

Read the full abstract...
Background: 

Trigger finger is a common clinical disorder, characterised by pain and catching as the patient flexes and extends digits because of disproportion between the diameter of flexor tendons and the A1 pulley. The treatment approach may include non-surgical or surgical treatments. Currently there is no consensus about the best surgical treatment approach (open, percutaneous or endoscopic approaches).

Objectives: 

To evaluate the effectiveness and safety of different methods of surgical treatment for trigger finger (open, percutaneous or endoscopic approaches) in adults at any stage of the disease.

Search strategy: 

We searched CENTRAL, MEDLINE, Embase and LILACS up to August 2017.

Selection criteria: 

We included randomised or quasi-randomised controlled trials that assessed adults with trigger finger and compared any type of surgical treatment with each other or with any other non-surgical intervention. The major outcomes were the resolution of trigger finger, pain, hand function, participant-reported treatment success or satisfaction, recurrence of triggering, adverse events and neurovascular injury.

Data collection and analysis: 

Two review authors independently selected the trial reports, extracted the data and assessed the risk of bias. Measures of treatment effect for dichotomous outcomes calculated risk ratios (RRs), and mean differences (MDs) or standardised mean differences (SMD) for continuous outcomes, with 95% confidence intervals (CIs). When possible, the data were pooled into meta-analysis using the random-effects model. GRADE was used to assess the quality of evidence for each outcome.

Main results: 

Fourteen trials were included, totalling 1260 participants, with 1361 trigger fingers. The age of participants included in the studies ranged from 16 to 88 years; and the majority of participants were women (approximately 70%). The average duration of symptoms ranged from three to 15 months, and the follow-up after the procedure ranged from eight weeks to 23 months.

The studies reported nine types of comparisons: open surgery versus steroid injections (two studies); percutaneous surgery versus steroid injection (five studies); open surgery versus steroid injection plus ultrasound-guided hyaluronic acid injection (one study); percutaneous surgery plus steroid injection versus steroid injection (one study); percutaneous surgery versus open surgery (five studies); endoscopic surgery versus open surgery (one study); and three comparisons of types of incision for open surgery (transverse incision of the skin in the distal palmar crease, transverse incision of the skin about 2–3 mm distally from distal palmar crease, and longitudinal incision of the skin) (one study).

Most studies had significant methodological flaws and were considered at high or unclear risk of selection bias, performance bias, detection bias and reporting bias. The primary comparison was open surgery versus steroid injections, because open surgery is the oldest and the most widely used treatment method and considered as standard surgery, whereas steroid injection is the least invasive control treatment method as reported in the studies in this review and is often used as first-line treatment in clinical practice.

Compared with steroid injection, there was low-quality evidence that open surgery provides benefits with respect to less triggering recurrence, although it has the disadvantage of being more painful. Evidence was downgraded due to study design flaws and imprecision.

Based on two trials (270 participants) from six up to 12 months, 50/130 (or 385 per 1000) individuals had recurrence of trigger finger in the steroid injection group compared with 8/140 (or 65 per 1000; range 35 to 127) in the open surgery group, RR 0.17 (95% CI 0.09 to 0.33), for an absolute risk difference that 29% fewer people had recurrence of symptoms with open surgery (60% fewer to 3% more individuals); relative change translates to improvement of 83% in the open surgery group (67% to 91% better).

At one week, 9/49 (184 per 1000) people had pain on the palm of the hand in the steroid injection group compared with 38/56 (or 678 per 1000; ranging from 366 to 1000) in the open surgery group, RR 3.69 (95% CI 1.99 to 6.85), for an absolute risk difference that 49% more had pain with open surgery (33% to 66% more); relative change translates to worsening of 269% (585% to 99% worse) (one trial, 105 participants).

Because of very low quality evidence from two trials we are uncertain whether open surgery improve resolution of trigger finger in the follow-up at six to 12 months, when compared with steroid injection (131/140 observed in the open surgery group compared with 80/130 in the control group; RR 1.48, 95% CI 0.79 to 2.76); evidence was downgraded due to study design flaws, inconsistency and imprecision. Low-quality evidence from two trials and few event rates (270 participants) from six up to 12 months of follow-up, we are uncertain whether open surgery increased the risk of adverse events (incidence of infection, tendon injury, flare, cutaneous discomfort and fat necrosis) (18/140 observed in the open surgery group compared with 17/130 in the control group; RR 1.02, 95% CI 0.57 to 1.84) and neurovascular injury (9/140 observed in the open surgery group compared with 4/130 in the control group; RR 2.17, 95% CI 0.7 to 6.77). Twelve participants (8 versus 4) did not complete the follow-up, and it was considered that they did not have a positive outcome in the data analysis. We are uncertain whether open surgery was more effective than steroid injection in improving hand function or participant satisfaction as studies did not report these outcomes.