Factors affecting prognosis in open A1 pulley release surgery for trigger finger

Abstract

Objectives: This study aims to investigate the frequency of recurrence and prolonged postoperative symptoms in patients undergoing open A1 pulley release for trigger finger and to identify potential associated factors.

Patients and methods: Between October 2021 and December 2023, a total of 72 patients (30 males, 42 females; mean age: 58.0±11.6 years; range, 32 to 84 years) who underwent trigger finger surgery with at least six months of follow-up were retrospectively analyzed. Patients were followed prospectively and relevant data were collected from patient files retrospectively. Demographics, finger symptoms, associated pathologies, clinical grades, Quinnell scores, Disabilities of the Arm, Shoulder and Hand (DASH) scores, grip strength, and surgeon experience were evaluated. Prolonged symptoms lasting over eight weeks postoperatively were also assessed.

Results: Comorbidities included carpal tunnel syndrome (13.89%), De Quervain tenosynovitis (13.89%), diabetes (8.33%), Bouchard's node (2.78%), ganglion cyst (8.33%), and calcium deposition (2.86%). Fourteen patients (19.44%) had additional trigger fingers. Loupe was used in 32 surgeries, resulting in significantly fewer prolonged symptoms (12.50% vs. 35.00%, p=0.028). The mean DASH scores significantly improved after surgery (53.07±13.43 vs. 18.41±11.26, p=0.000), with a greater improvement in the loupe group (46.52±6.50 vs. 25.18±13.96, p=0.0000). The mean grip strength did not significantly differ between the surgical and control sides in the loupe group (27.29±7.58 vs. 26.36±7.85 lb, p=0.0887); however, it was weaker on the surgical side in the nonloupe group (23.87±7.81 vs. 25.28±6.96 lb, p=0.0067). Loupe usage was the sole significant factor which was absent in 77.78% of the patients with prolonged symptoms.

Conclusion: Trigger finger surgery, though typically simple and routine, may benefit from loupe-assisted procedures due to reduced postoperative symptoms and improved functional outcomes. Consideration of loupe use is warranted in such surgeries.

Introduction

Trigger finger results from a discrepancy between the diameter of the flexor tendon and the A1 pulley through which it passes. Trigger finger, causing prolonged pain, deformity in the finger, and disability, is a common condition in adults with a lifetime risk of around 2%.[1]

Conservative treatment is initially attempted, and when unsuccessful, surgical release of the A1 pulley is recommended for trigger finger patients. The overall success rate of A1 pulley release is up to 97%, and the literature is contentious regarding which surgical technique among open, percutaneous, and endoscopic approaches is superior.[2] Open A1 pulley release is highly successful; however, the time to recovery varies among patients despite its simplicity and usually satisfactory outcomes.[3]

Atthakomol et al.[4] reported permanent symptoms or recurrence of adult trigger finger in 2.39% of cases following open trigger finger release. In a study assessing risk factors for long-term symptoms post-surgery, Baek et al.[5] found that 19% of patients experienced discomfort or limited range of motion (ROM) for more than eight weeks after the operation. Several reports have indicated that demographic characteristics and pathophysiological factors of the patient also influence the outcome post-A1 pulley release.[5-7]

In the present study, we aimed to examine the frequency of long-term postoperative symptoms such as pain or discomfort and ROM limitation, as well as factors determining prognosis following open A1 pulley release.

Patients and Methods

This single-center, retrospective study was conducted at Ankara University Faculty of Medicine, Department of Orthopaedics Traumatology and Hand Surgery between October 2021 and December 2023. Patients who underwent surgery for the trigger finger and had a follow-up of at least six months at our clinic were included. Patients were identified through the hospital information system using the "trigger finger" ICD (M65.3) and surgery (612050) code, resulting in 213 patients being reached. Of 84 eligible patients, only 72 (30 males, 42 females; mean age: 58.0±11.6 years; range, 32 to 84 years) who met the inclusion criteria and agreed to participate were recruited. The study flowchart is shown in Figure 1. A written informed consent was obtained from each patient. The study protocol was approved by the Ankara University Faculty of Medicine Ethics Committee (date: 21.05.2024, no: 2024000293). The study was conducted in accordance with the principles of the Declaration of Helsinki.

Figure 1. Study flowchart.

Demographic data, symptomatic finger and number of fingers, additional pathologies such as carpal tunnel syndrome (CTS), De Quervain's tenosynovitis, Bouchard's node, ganglion cyst, clinical grade, Quinnell score, Disabilities of the Arm, Shoulder and Hand (DASH) score, and grip strength were evaluated. Prolonged postoperative symptoms were specifically investigated by querying and assessing patients during follow-up visits for symptoms such as pain and triggering over the A1 pulley. Recurrence of trigger finger was defined as the return of these symptoms after a symptom-free period of more than one month. Additionally, triggering, locking, pain, and motion restriction that persisted for more than eight weeks after surgery were considered prolonged postoperative symptoms. Additionally, the experience of the operating surgeon and its effects were investigated; the surgeon's experience was assessed according to Tang and Giddins’s method.[8] The patients were separately evaluated in two groups as those receiving the loupe (n=32) and those who did not (n=40).

Surgical technique

All trigger finger release operations were performed using the wide-awake local anesthesia no tourniquet (WALANT) technique. The doses for WALANT were 1% lidocaine with 1:100,000 epinephrine and 8.4% bicarbonate mixed in 1 mL:10 mL. The skin was incised longitudinally, obliquely, or transversely at the level of the metacarpophalangeal joint. Subcutaneous tissue was bluntly dissected and only vertically, with a pair of retractors placed on each side. The boundaries of the A1 pulley were precisely identified and completely longitudinally incised, with no manipulation of the A2 pulley. Subsequently, an assessment of both the active and passive ROM of the affected finger was conducted to confirm smooth gliding of the flexor tendon without any catching. Finally, the incision was closed with 4-0 or 5-0 nylon sutures, followed by the application of a bulky bandage. Postoperatively, all patients were encouraged to perform exercises to maintain an active ROM of the affected finger. Sutures were removed from all patients within two weeks, followed by initiation of scar massage with Bepanthol® (Bayer AG, Leverkusen, Germany) cream.

Statistical analysis

Statistical analysis was performed using the Stata version StataMP13 software (Stata Corp., College Station, TX, USA). The Shapiro-Wilk test was employed to evaluate the normality of the data distribution. Continuous variables were expressed in mean±standard deviation (SD) or median (min-max), while categorical variables were expressed in number and frequency. Categorical variables were analyzed using the chi-square and Fisher exact tests. Parametric data comparisons between the groups were performed using the t-test, while non-parametric data were assessed with the Mann-Whitney U test. The Wilcoxon signed-rank test was utilized for comparing dependent groups in pre-post assessments. A p value of <0.05 was considered statistically significant.

Results

Baseline demographic, clinical, and functional characteristics of the patients are summarized in Table I. Prolonged symptoms were observed in 18 patients (25%), while recurrence was seen in 4 patients (5.56%). No major complications of open A1 pulley release for trigger finger were observed in any patient.

Loupe was used in the surgery of 32 patients, while it was not used in 40 patients. Prolonged symptoms were significantly less and DASH score improvement was significantly more in the loupe group. The mean DASH scores significantly improved after surgery (53.07±13.43 vs. 18.41±11.26, p<0.001), with a greater improvement in the loupe group (46.52±6.50 vs. 25.18±13.96, p<0.001). The mean grip strength did not significantly differ between the surgical and control sides in the loupe group (27.29±7.58 vs. 26.36±7.85 lb, p=0.0887); however, it was weaker on the surgical side in the non-loupe group (23.87±7.81 vs. 25.28±6.96 lb, p=0.0067). Loupe usage was the sole significant factor which was absent in 77.78% of the patients with prolonged symptoms. The use of loupe was more common among senior surgeons (p<0.001).

The mean time from surgery until complete resolution of symptoms was 4.185±1.167 weeks. However, in 25% of the patients with prolonged symptoms, the mean time to recovery was longer (13.611±4.146 weeks). No significant factors were identified while comparing demographic factors, additional pathologies, preoperative flexion contracture, symptom duration, or surgeon experience between the groups with and without prolonged symptoms, except for loupe usage. Among 18 patients with prolonged symptoms, loupe was not used in 14 patients (77.78%).

Discussion

In the present study, we investigated the frequency of recurrence and prolonged postoperative symptoms in patients undergoing open A1 pulley release for trigger finger and identified potential associated factors. The sole determinant of postoperative prolonged symptoms was the surgeon's experience and the use of loupe.[9] Our study findings revealed relatively high rates of prolonged postoperative symptoms and recurrence following A1 pulley release. In comparison with a similar study involving 723 patients, which reported a recurrence rate of 2.39%,[4] our results highlight the prevalence of the recurrent symptoms associated with multiple steroid injections and manual labor. Among our patients with recurrence, several received multiple steroid injections, with two being homemakers and one diagnosed with type 2 diabetes mellitus. Notably, the ulnar superficialis slip resection (USSR) procedure was performed at the sixmonth follow-up in recurrence cases. Although USSR procedure was warranted, the initial surgery involved A1 pulley release.

In a study involving 136 patients, the severity of various flexor tendon degenerations affected the outcome of open trigger finger release surgery at one month, but did not affect the outcome at three and six months postoperatively.[10] In our routine practice, we usually proceed to the USSR procedure in case of strong evidence of flexor digitorum superficialis (FDS) degeneration during surgery. Figure 2 demonstrates a USSR case.

Figure 2. An example case of ulnar superficialis slip resection.

Strigelli et al.[11] found that isolated A1 pulley release did not always ensure complete tendon mobility, emphasizing the benefit of simultaneous A1-A2 pulley release. While the debate continues on whether sacrificing one leg of the FDS tendon or the A2 pulley itself is preferable, we believe that sacrificing one leg of the degenerated tendon reduces sheath volumwe while largely preserving the A2 pulley, which may not be entirely pathological.

In the current study, the mean time from surgery until complete resolution of symptoms was 4.185±1.167 weeks. However, in 25% of the patients with prolonged symptoms, recovery took longer. This finding indicates that complete recovery within one month is not always achieved with A1 pulley release alone, highlighting the potential benefit of postoperative splinting or other interventions to expedite recovery. A significant contribution of the study is the identification of surgical loupe dissection as an effective factor on prolonged postoperative symptoms. Microdissection with loupes improved visualization, reduced tissue damage, and expedited recovery. This technique enhanced outcomes by minimizing complications and supporting faster rehabilitation.

Nonetheless, this study has some limitations. First, it has a single-center, retrospective design with a relatively small sample size. Due to the low number of recurrences and the absence of major complications, statistical analysis was constrained. Second, the heterogeneity of the patient population, including variations in age, gender, and comorbid conditions, may limit the generalizability of the findings. Third, the relatively short follow-up period of 10.75 months might be insufficient to assess longterm outcomes comprehensively. Additionally, the evaluation of certain symptoms relied on patient self-reporting, which could introduce recall bias or inaccuracies. Further large-scale, long-term, prospective studies are needed to confirm these findings.

In conclusion, trigger finger surgery benefits significantly from the use of loupes which facilitate atraumatic surgery, leading to fewer prolonged symptoms and improved functional outcomes. Based on these findings, we recommend their use to reduce postoperative complications and enhance recovery in these patients.

Citation: Bezirgan U, Bekar H, Dursun Savran M, Yoğun Y, Armangil M. Factors affecting prognosis in open A1 pulley release surgery for trigger finger. Jt Dis Relat Surg 2025;36(1):78-84. doi: 10.52312/ jdrs.2024.1885.

Idea/concept: U.B., H.B.; Design, materials, literature review: Y.Y., H.B.; Control/supervision: M.A.; Data collection and/or processing: M.D.S., H.B.; Analysis and/or interpretation: M.D.S.; Writing the article: M.D.S., U.B.; Critical review: U.B., M.A.; References and fundings: Y.Y.

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

The authors received no financial support for the research and/or authorship of this article.

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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