A1 Pulley Reconstruction for Severe Trigger Finger

Summary

Here, we present a protocol to compare A1 pulley reconstruction with traditional release surgery in treating a trigger finger, revealing enhanced outcomes and patient satisfaction through the Michigan Hand Outcomes Questionnaire.

Abstract

The aim of this study was to evaluate the effectiveness of A1 pulley reconstruction in treating severe trigger fingers and to compare its outcomes with those of the traditional A1 pulley release technique. A total of 43 patients participated in the study, divided into two groups: 22 patients underwent A1 pulley reconstruction, while the remaining 21 patients received the standard A1 pulley release procedure. The outcomes were assessed using the Michigan Hand Outcomes Questionnaire (MHQ) 1 month post-surgery. The results demonstrated that patients who received the A1 pulley reconstruction reported significantly better outcomes. These included enhanced hand function and quality of life, reduced levels of pain, improved aesthetic appearances, and higher overall satisfaction when compared to the traditional release group. The findings suggest that A1 pulley reconstruction offers superior benefits over the standard release procedure for individuals suffering from severe trigger fingers, highlighting its potential as a more effective surgical intervention.

Introduction

Trigger finger, medically known as stenosing tenosynovitis, is a condition that occurs when the flexor tendon sheath, which facilitates the smooth gliding of tendons within the finger, becomes inflamed and narrowed, and mostly a palpable nodule is present at the affected site^1,2. This constriction impedes the tendon's ability to move freely, leading to the characteristic catching or snapping sensation³. Distinguishing between association and causation is crucial. The majority of trigger digits are considered idiopathic, meaning that their cause is unknown. However, recent studies suggest that individuals with high blood sugar levels and diabetes are at a higher risk of developing trigger finger⁴. The primary causes of the trigger finger include repetitive hand movements, prolonged gripping activities, and underlying conditions such as rheumatoid arthritis^5,6,7. The condition often progresses through stages, beginning with mild discomfort and progressing to severe limitations in finger mobility. In its initial phases, the trigger finger may present with occasional stiffness or a clicking sensation. However, as the inflammation worsens, the affected finger may become increasingly difficult to extend or flex, resulting in pain and a noticeable impairment of function^8,9.

A severe trigger finger can have a profound impact on an individual's ability to perform routine tasks; simple activities like grasping objects, typing, or even buttoning a shirt become arduous and painful. The condition may interfere with professional responsibilities and hinder personal enjoyment, leading many to seek effective and lasting solutions.

Corticosteroid injections are commonly used to treat symptoms, with a success rate ranging from 40% to 90%^1,10,11. Injecting a corticosteroid into the tendon sheath is effective for more than half of people, providing relief lasting weeks to months¹². On the other hand, corticosteroid injection is associated with various complications, including tendon weakness or rupture and site infection¹³. If nonsurgical treatment is unsuccessful or symptoms are severe, a surgical A1 pulley release may be necessary¹⁴. A1 pulley release is generally considered a low-risk procedure. However, Nathan et al. conducted a study on 543 patients who underwent 795 digits release, which found that 12% experienced swelling, stiffness, persistent pain, infections, or recurrent triggering. These complications were treated non-operatively, and only 2.4% of the patients required another surgery¹⁵.

Therefore, in this article, we present guidance on a procedure for severe trigger fingers with better outcomes, which includes expansion and reconstruction of the A1 pulley, along with preoperative and postoperative management.

The inclusion and exclusion criteria for this study are given below.

The inclusion criteria are as follows: (1) Patients diagnosed with severe trigger fingers requiring surgical intervention. (2) Adult patients aged between 18 and 75 years. (3) Symptoms of trigger finger lasting at least 6 months and unresponsive to conservative treatments (e.g., medication, physical therapy). (4) Patients willing to undergo surgery and sign an informed consent form. (5) Patients willing to complete the MHQ¹⁶ preoperatively and one month postoperatively.

The exclusion criteria are as follows: (1) Patients with severe systemic diseases (e.g., uncontrolled diabetes, heart disease, renal failure) that could affect surgical outcomes or recovery. (2) Patients who have previously undergone any form of surgical treatment on the affected finger (e.g., prior A1 pulley release surgery). (3) Presence of acute or chronic infection or severe inflammation in the affected finger or hand. (4) Patients with neurological disorders affecting hand function (e.g., peripheral neuropathy). (5) Pregnant women. (6) History of mental health conditions that could interfere with postoperative follow-up and assessment. (7) Patients unwilling or unable to participate in the one-month postoperative follow-up and MHQ assessment.

Protocol

Written informed consent was obtained from the patients for publication. This surgical protocol adheres to the ethical standards established by the human research ethics committee of Zhejiang University School of Medicine.

1. Preoperative evaluation

1. Review the patient's medical history thoroughly, including the duration and severity of trigger finger symptoms.
2. Conduct a clinical examination, including finger mobility and the presence of nodules.
3. Perform imaging studies, such as ultrasound or MRI, to confirm the diagnosis and assess the extent of tendon involvement.

2. Informed consent

1. Inform about the surgical procedure, potential risks, benefits, and alternatives. In addition, obtain written consent.

3. Anesthesia and preparation

1. Administer axillary plexus block anesthesia to ensure pain-free surgery after sterilizing the injection site with lodine.
2. Prepare the required surgical instruments, including a scalpel with a 15-blade, scissors, forceps, and electrosurgery.
3. Apply an upper-arm tourniquet to control bleeding at 40 Kpa.
4. Extend the patient's arm and position the hand on the surgical table after sterilizing the operation site with iodine.

4. Surgical procedure

1. Make an "S"-shaped incision, approximately 3 cm in length, on the palmar side of the metacarpophalangeal (MCP) joint of the affected finger. Begin the incision at the distal end of the MCP joint, extending it proximally while following the natural contours of the skin. Ensure the curves of the "S" shape allow for better access to the underlying structures, reducing tension on the incision during closure.
2. Carefully extend the incision and thoroughly remove subcutaneously inflamed tissue.
3. Open the A1 pulley with a palm-side "Z" incision (Figure 1), forming one triangular flap of equal size and shape on each side, which is typically designed at an angle of approximately 60°. Along the incision, carefully release the A1 pulley. While in the release group, incise the A1 pulley along the length of the pully.
   NOTE: Inflamed tissue surrounding the flexor tendons was cleared to ensure free movement along with the removal of proliferative tendon sheaths.
4. Reconstruct the pulley using a Z-shaped technique by rotating and exchanging the flaps, then suture them together with 4-0 polydioxanone (PDS) sutures (Figure 2). Ensure the size of the reconstructed pulley allows smooth tendon gliding and prevents entrapment (Figure 2).
5. Close the skin using 4-0 silk sutures and apply a sterile dressing.

5. Postoperative management

1. Closely monitor the patient in the immediate postoperative period.
2. Initiate passive joint exercises on the second day after surgery.
3. Remove sutures after 2 weeks.
4. Instruct the patient to begin active joint exercises under medical supervision.

6. Rehabilitation

1. Advise the patient to follow a prescribed rehabilitation program to regain full finger function through stretching and strengthening exercises of the affected part.
   NOTE: Finger exercises are initiated on the third postoperative day, comprising two distinct phases. The initial phase involves passive range-of-motion exercises, during which the healthcare providers sequentially flex and extend each finger 10 times. The subsequent phase encompasses active range-of-motion exercises, requiring the patient to align the thumb with each of the other four fingers successively. Following each thumb alignment, the thumb is returned to its initial position before proceeding to the next alignment, to be repeated 10 times. The patient regains functional capabilities in the surgical hand 1 month post-surgery.

7. Follow-up

1. Schedule monthly follow-up appointments to assess the patient's progress, including improved finger movement, daily living activities, work, and pain reduction. Maintain follow-up for 3 months.

Results

The surgical intervention resulted in the successful removal of subcutaneous inflamed tissue, allowing for improved mobility of the flexor tendons (Figure 1B). Reconstruction of the A1 pulley with 4-0 PDS sutures contributed to the restoration of smooth tendon gliding and effectively prevented entrapment (Figure 3). The reconstructed pulley demonstrated an appropriate size, ensuring optimal functionality. Skin closure with sutures completed the procedure.

Discussion

Severe trigger finger, characterized by persistent pain, locking, and impaired finger movement, often proves resistant to nonsurgical treatments. In such instances, surgical intervention becomes a necessary consideration¹. Percutaneous release procedures may be considered in some cases. This minimally invasive technique involves a needle being inserted into the tissue around the affected tendon, and a needle is used to break apart the constricting portion of the tendon sheath. Nakagawa et al. inve...

Materials

Name	Company	Catalog Number	Comments
Blade #15	Hwato	20152020630
Electrosurgery unit	ECO	20152154637
Forceps	JZ	20140023
PDS*Plus Antibacterrial Polydioxanone violet Monofilament Suture 4-0	Johnson & Johnson	130705031047870	Surgical Suture Thread
Scalpel handle 7#	JZ	20161010
Scissors	JZ	20140012
Silk suture 4-0	WEGGO	20152020252	Surgical Suture Thread
Tourniquet	Zimmer	20162143149