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Trigger finger release

Surgeon-side topic for trigger finger release. Backed by 278 articles from the corpus, retrieved via combined MeSH + title-text matching.

Overview

Open trigger finger release is a low-risk, short procedure considered the treatment of choice for locked pediatric trigger thumb [1, 24]. While complications can occur and occasionally require reoperation [1], clinic-based open releases demonstrate complication rates comparable to those performed in the operating room [3]. Percutaneous release is also safe and efficacious across all digits, including the thumb, index, and small fingers [4, 12], though the clinical significance of ultrasound guidance remains unclear despite confirming safety [8].

Surgical management strategies vary by cost and clinical presentation. Management with two steroid injections prior to surgery represents the least costly strategy [31], whereas immediate surgical release in the clinic is most cost-effective for diabetic patients assuming a corticosteroid injection failure rate of at least 34% [27]. Patients undergoing surgical release alone face significantly higher odds of developing new-onset Dupuytren disease and subsequent fasciectomy compared to those managed with other interventions [34]. Simultaneous steroid injection at the time of percutaneous release provides greater early subjective improvement [2], while the thread technique has shown immediate resolution of triggering with no observed complications [16].

Anatomy & Pathophysiology

Trigger finger (stenosing tenosynovitis) involves mechanical impingement of the flexor tendons at the A1 pulley [29]. The condition is characterized by pain and tenderness in the palm at the proximal edge of the digital A1 pulley [14]. Patients frequently note catching or triggering of the affected finger or thumb after forceful flexion [14], often more pronounced in the morning than later in the day [14]. In severe cases, the opposite hand must be used to force the finger or thumb passively into extension [14], while in the most severe cases, the finger becomes locked in a flexed position [14]. Triggering is often described by patients as occurring in the proximal interphalangeal joint with trigger finger or the proximal interphalangeal joint with trigger thumb [19], and pressure accentuates the apparent snapping or triggering of the more distal joints [19]. A palpable lump or knot may be present in the palm, representing a thickened area in the first annular pulley or a nodule of the flexor tendon [19], though local tenderness may be present but is not a prominent complaint in adults [19].

Pathologic examination of affected pulleys demonstrates a proliferation of chondrocytes and increased type III collagen [29], with histology showing fibrocartilaginous metaplasia in the pulley and/or flexor digitorum superficialis tendon [5, 6]. The flexor digitorum profundus tendon often demonstrates a pathologic nodule, while the flexor digitorum superficialis is often unaffected [29]. An intratendinous nodule may be present proximal to the first annular pulley, often referred to as Notta's nodule [51], usually just proximal to the anulus at the metacarpophalangeal joint level in adults [19]. In rheumatoid patients, a nodule distal to the metacarpophalangeal joint level may cause triggering [19]. A volar retinacular ganglion cyst may be present between the A1 and A2 pulleys [29], and fixed flexion deformity of the proximal interphalangeal joint may be present [29].

Trigger finger is more common in women older than 50 years of age [5, 6], with the middle and ring fingers being the most commonly involved digits in adults [5, 6]. The digits are affected in order of decreasing prevalence: thumb, ring, long, little, and index [29]. Trigger finger is more common in diabetic patients than in nondiabetic patients [14], with a 10% to 20% lifetime incidence in patients with diabetes mellitus [29]. When multiple digits are involved, the possibility of diabetes should be considered [14]. Trigger finger is associated with inflammatory arthropathy and rheumatoid arthritis [5, 6], as well as hypothyroidism, sarcoidosis, and septic tenosynovitis [29]. Gout can mimic infectious tenosynovitis and result in triggering due to monosodium urate precipitation [29], while calcific tendinitis can resemble an infection and result in triggering due to calcium salt deposition in the tenosynovium [29]. Pseudogout involves calcium pyrophosphate dihydrate crystal deposition that can cause triggering [29], and amyloidosis, characterized by beta-2-microglobulin deposition, is seen in patients with renal failure undergoing dialysis and can cause triggering [29]. Trigger finger is associated with Dupuytren's disease, with a higher incidence in the middle and ring fingers [56], and the percentage of patients with both trigger finger and Dupuytren's disease increases with age [56]. In patients with Dupuytren's disease, thickening of the pulley wall leads to narrowing of the A1 pulley and synovial congestion [57], though in advanced stages of Dupuytren's contracture (Stages II or III), concomitant trigger finger is rarely seen [57]. Concomitant trigger finger and carpal tunnel syndrome occurs in 40% to 60% of patients [5, 6].

The pulley system of the thumb is composed of 4 components, contrary to the traditional view of only 3 [49], with the fourth pulley (variable annular pulley) found in 75% of patients and may contribute to stenosis in the thumb [5, 6]. A1 pulley confluence varies on a digit-to-digit basis, with no observed confluence in the thumb and the most common confluence in the middle finger [62]. In the thumb, the flexor tendon and A1 pulley thicken significantly only after patients exhibit triggering [72], and triggering in the thumb is often more pronounced in the morning than later in the day [14]. Cutoff values for the cross-sectional area ratio of a specific part of the flexor pollicis longus tendon are 1.153 for adults and 1.362 for children to distinguish trigger thumb from healthy thumbs [69]. Repetitive power grip and flexion activities, such as ocean rowing, increase the prevalence of trigger finger [71]. Patients with greater volar migration of the flexor tendons after carpal tunnel release are at a higher risk of developing trigger finger [63], and triggering can occur after carpal tunnel release due to volar migration of the flexor tendons [63]. Trigger finger can occur after operative release due to catching of the tendon on the palmar aponeurosis transverse fibers [19], and occasionally, a partially lacerated flexor tendon at the A1 pulley level heals with a nodule sufficiently large to cause triggering [19].

In children, congenital trigger digits typically show a persistent flexion deformity rather than actual "triggering" [51]. Congenital trigger digits occur far more commonly in the thumb and are bilateral in about 25% of patients [51]. Spontaneous resolution occurs in about 30% of children with congenital trigger digits appearing within the first year of life [51], in about 12% of children with congenital trigger digits appearing between 6 months and 2 years of age [51], and Baek et al. noted spontaneous resolution in 63% of children over a median of 48 months [51]. Congenital trigger digits are associated with trisomy 13 and mucopolysaccharidosis [51]. In pediatric trigger fingers, surgical intervention has a high likelihood of restoring motion and function [52], while pediatric trigger thumb responds universally to simple surgical release [30]. Pediatric trigger fingers are more complex than trigger thumbs, often owing to systemic conditions or anatomical abnormalities [30], yet loss of motion in pediatric trigger thumb is still reversible even after 21 years, with normal function obtainable with late presentation [36].

In the thumb, the radial digital nerve is at risk of iatrogenic injury during release due to its superficial location [5, 6], and the digital nerves on the thumb are more palmar and closer to the flexor sheath than might be anticipated [15]. The thumb radial digital nerve is especially vulnerable during trigger thumb release [15]. A1 pulley division usually leaves divided pulley leaves parallel rather than ending in a V-shaped pattern when the distal A1 pulley edge is released [15]. In patients with rheumatoid arthritis, the entire annular pulley system should be preserved to prevent further ulnar drift of the fingers [14]. In patients with rheumatoid arthritis, triggering is treated by tenosynovectomy and excision of one slip of the flexor digitorum superficialis [14], with excision of a slip of the FDS tendon preferred over release of the A1 pulley to avoid exacerbating ulnar drift at the MCP joint [5, 6]. Triggering in patients with rheumatoid arthritis may be treated by excision of one or both slips of the flexor digitorum superficialis tendon and release of the A3 pulley [51].

Classification

Epidemiology and Etiology: Trigger finger is most prevalent in women older than 50 years of age [5, 6], with the middle and ring fingers being the most commonly involved digits in adults [5, 6]. The condition is associated with diabetes and inflammatory arthropathy [5, 6], and repetitive grasping activities may contribute to its etiology [5, 6]. Histologically, the disease is characterized by fibrocartilaginous metaplasia of the pulley and/or flexor digitorum superficialis (FDS) tendon [5, 6].

Clinical Presentation: Patients typically present with pain and tenderness in the distal palm [5, 6], often reporting referred pain at the dorsal metacarpophalangeal (MCP) or proximal interphalangeal (PIP) area [5, 6]. The clinical course progresses from pain to mechanical catching and locking, which may eventually become fixed [5, 6]. Concomitant trigger finger and carpal tunnel syndrome (CTS) occurs in 40% to 60% of patients [5, 6]. Additionally, a fourth pulley (variable annular pulley) is found in 75% of patients with thumb trigger finger [5, 6].

Grading System: Grade I: Defined as pain and tenderness at the A1 pulley [5, 6]. Grade II: Defined as catching of the finger [5, 6]. Grade III: Defined as locking of the finger that is passively correctable [5, 6]. Grade IV: Defined as a fixed, locked finger [5, 6].

Other Considerations: Corticosteroid injection into the flexor tendon sheath is a nonoperative treatment for trigger finger [5, 6]. This intervention is curative in about 60% of patients initially [5, 6], though diabetic patients are generally less responsive to corticosteroid injection [5, 6]. There is no difference in efficacy between soluble and insoluble corticosteroid preparations for trigger finger [5, 6].

Clinical Presentation

Trigger finger is characterized by pain and tenderness in the distal palm at the proximal edge of the digital A1 pulley [5, 14]. Patients frequently note catching or triggering of the affected finger or thumb after forceful flexion, often more pronounced in the morning [14]. In severe cases, the opposite hand must be used to force the digit passively into extension, while the most severe presentations involve the finger becoming locked in a flexed position [14]. Patients may experience referred pain at the dorsal MCP or PIP area [5], and a palpable lump or knot may be present in the palm representing a thickened area in the first annular pulley or a nodule of the flexor tendon just distal to it [19]. The tendon nodule is usually located just proximal to the anulus at the metacarpophalangeal joint level [19].

Classification: Clinical severity is stratified by the Green grading system: Grade I includes pain and tenderness at the A1 pulley [5, 29]; Grade II includes catching without locking [5, 29]; Grade III includes locking that is passively correctable [5, 29]; and Grade IV includes a fixed, locked finger [5, 29]. A fixed flexion deformity of the proximal interphalangeal joint may be present on physical examination [29]. Patients frequently state that the problem is in the proximal interphalangeal joint with trigger finger or in the proximal interphalangeal joint with trigger thumb [19]. This PIP joint pain results from long symptom duration and consequent joint pathology [21], and it is incompletely resolved after A1 pulley release, leading to worse surgical outcomes than expected [21].

Epidemiology and Risk Factors: Trigger finger occurs in 2% to 3% of the general population, with women more commonly affected than men [29]. The digits are affected in the following order of decreasing prevalence: thumb, ring, long, little, and index [29]. Middle and ring finger involvement is most common in adults [5], and trigger thumb and trigger finger are usually seen in individuals older than 45 years of age [19]. Trigger finger is more common in patients with systemic diseases such as diabetes mellitus (10% to 20% lifetime incidence), hypothyroidism, sarcoidosis, rheumatoid arthritis, and septic tenosynovitis [29]. Stenosing tenosynovitis is more common in diabetic patients than in nondiabetic patients [14], and when multiple digits are involved, the possibility of diabetes should be considered [14]. Concomitant trigger finger and carpal tunnel syndrome occurs in 40% to 60% of patients [5].

Pathology and Differential Diagnosis: Pathologic examination demonstrates a proliferation of chondrocytes and increased type III collagen in the affected pulleys [29]. The flexor digitorum profundus tendon often demonstrates a pathologic nodule, while the flexor digitorum superficialis is often unaffected [29]. Histology shows fibrocartilaginous metaplasia of the pulley and/or flexor digitorum superficialis tendon [5]. A fourth pulley (variable annular pulley) is found in 75% of patients with trigger thumb, which may contribute to stenosis [5]. Trigger finger is associated with repetitive grasping activities [5]. In patients with rheumatoid arthritis, a nodule distal to the metacarpophalangeal joint level may cause triggering, and several fingers may be involved [19]. Trigger thumb in adults is a distinctly separate entity from congenital trigger thumb [19].

Differential Diagnosis: Gout initial presentation can mimic infectious tenosynovitis with marked pain, erythema, swelling, and warmth [29]. Calcific tendinitis can resemble an infection and result in triggering [29]. Pseudogout is characterized by calcium pyrophosphate dihydrate crystal deposition often localized to the triangular fibrocartilage or within the carpal tunnel [29]. Amyloidosis is characterized by deposition of beta-2-microglobulin along the flexor tendons, most commonly seen in patients with renal failure undergoing dialysis [29]. Intraarticular disorders such as loose bodies, degenerative joint disease, and fractures can cause symptoms similar to trigger finger [19]. Common extensor tendon subluxation can cause symptoms similar to trigger finger [19]. A volar retinacular ganglion cyst may be present between the A1 and A2 pulleys [29].

Treatment Response and Complications: Corticosteroid injection is "curative" in about 60% of patients initially [5]. 65% to 90% of patients who do not have diabetes obtain relief of symptoms with one or two injections [29]. In patients with diabetes, relief of symptoms after injection is less reliable and may depend on chronic glucose levels [29], and diabetic patients are generally less responsive to injection [5]. Female patients presenting with their first trigger finger have the highest rate of long-term treatment success after a single corticosteroid injection [23]. A single corticosteroid injection for trigger finger has a 45% long-term success rate [41], and success beyond two years after a single corticosteroid injection likely predicts lasting symptom relief [41]. Results of corticosteroid injection vary by sex and number of affected digits [41]. Repeat corticosteroid injections provided symptomatic relief for a year or more in 50% of patients in one study [19], while 39% of second and third corticosteroid injections for trigger finger yield long-term relief [26]. No difference exists between soluble and insoluble corticosteroid preparations regarding efficacy [5]. Corticosteroid injections may elevate serum glucose levels for 5 days or more in patients with diabetes mellitus [19]. Preoperative hypoglycemia increases infection risk after both trigger finger injection and release [19].

Surgical Outcomes and Risks: Approximately 97% of patients have complete resolution after operative treatment [19]. Surgical release of the A1 pulley provides satisfactory results in greater than 90% of patients [29]. Persistence of triggering is more common than recurrence after surgical release [19]. Subsequent release or injection in the same or another digit is common following an initial trigger finger release [11]. Minor complications following trigger finger release are prominent, though major complications are unlikely [33]. Minor complications include wound dehiscence, scar tenderness, and decreased range of motion [5]. Incomplete pulley release and damage to the flexor tendons and digital nerves remain concerns with limited exposure techniques, especially in the index finger and thumb [19]. The radial digital nerve is at risk of iatrogenic injury during thumb trigger finger release due to its superficial location [5]. On the thumb, digital nerves are more palmar and closer to the flexor sheath than might be anticipated [15], and the thumb radial digital nerve is especially vulnerable during trigger finger release [15]. Physicians should consider the duration of preoperative symptoms and preoperative flexion contracture of the PIP joint when deciding timing of surgery [32].

Investigations

Clinical Presentation: Trigger finger is more common in women older than 50 years of age [5, 29], with the middle and ring fingers being the most commonly involved digits in adults [5, 29]. The condition occurs in 2% to 3% of the general population [29] and is associated with diabetes, inflammatory arthropathy, hypothyroidism, sarcoidosis, rheumatoid arthritis, and septic tenosynovitis [5, 29]. Patients with diabetes mellitus have a 10% to 20% lifetime incidence [29]. Repetitive grasping activities may be associated with the etiology [5]. Clinical presentation includes pain and tenderness in the distal palm at the proximal edge of the digital A1 pulley [5, 14], often with referred pain at the dorsal MCP/PIP area [5]. Patients frequently note catching or triggering after forceful flexion, which is often more pronounced in the morning [14]. In severe cases, the opposite hand must be used to force the finger passively into extension, or the finger becomes locked in a flexed position [14].

Physical Examination: Examination may reveal tenderness to palpation of the flexor tendon at the level of the A1 pulley [29], palpable triggering or pain with flexion and extension [29], and nodularity of the flexor tendon just proximal to the A1 pulley [29]. A volar retinacular ganglion cyst may be present between the A1 and A2 pulleys [29], and a fixed flexion deformity of the proximal interphalangeal (PIP) joint may be present [29]. Concomitant trigger finger and carpal tunnel syndrome (CTS) occurs in 40% to 60% of patients [5].

Classification: The Green grading system defines Grade I as pain and tenderness at the A1 pulley [5, 29], Grade II as catching of the finger [5, 29], Grade III as locking of the finger that is passively correctable [5, 29], and Grade IV as a fixed, locked finger [5, 29].

Histopathology: Histology demonstrates fibrocartilaginous metaplasia of the pulley and/or flexor digitorum superficialis (FDS) tendon [5, 29]. Pathologic examination of affected pulleys shows a proliferation of chondrocytes and increased type III collagen [29]. The flexor digitorum profundus tendon often demonstrates a pathologic nodule, while the flexor digitorum superficialis is often unaffected [29].

Differential Diagnosis: Gout can mimic infectious tenosynovitis with initial presentation of marked pain, erythema, swelling, and warmth [29]. Calcific tendinitis can resemble an infection and result in triggering; males are affected five times more frequently than females [29]. Pseudogout involves calcium pyrophosphate dihydrate crystal deposition often localized to the triangular fibrocartilage or within the carpal tunnel [29]. Amyloidosis is characterized by deposition of beta-2-microglobulin along flexor tendons, most commonly seen in patients with renal failure undergoing dialysis [29]. A case of volar wrist ganglion presenting as trigger finger was treated with interventional radiological measures rather than open surgery [53].

Other Considerations: A newer finding identifies a fourth pulley (variable annular pulley) in 75% of patients with trigger thumb, which may contribute to stenosis [5]. Corticosteroid injection into the flexor tendon sheath is a nonoperative treatment option [5, 14, 29]. Injection is considered "curative" in about 60% of patients initially [5]. In patients without diabetes, 65% to 90% obtain relief of symptoms with one or two injections [29]. Female patients presenting with their first trigger finger have the highest rate of long-term treatment success after a single corticosteroid injection [23]. Diabetic patients are generally less responsive to injection [5], and relief in these patients may depend on chronic glucose levels (hemoglobin A1c levels) [29]. There is no difference in efficacy between soluble and insoluble steroid preparations [5]. Ultrasound-guided corticosteroid injections are more effective than the blinded method, leading to better results and faster return to work in early stages [64]. Percutaneous trigger finger release can safely be performed on all digits, including the thumb, small fingers, and index fingers [4], and is safe for the thumb, index, middle, and ring fingers as long as the recommended technique is observed [9]. However, ultrasound guidance does not provide a clinical advantage over blinded percutaneous release [12], and the safety and efficacy of percutaneous trigger finger release, even with ultrasound guidance, have raised questions regarding its safety [8]. Open trigger finger release is generally a low-risk procedure, although there is potential for complications, some requiring reoperation [1]. Patients who undergo open trigger finger release surgery in the clinic have complication rates similar to those performed in the operating room [3]. Surgical release of the A1 pulley is curative in digits refractory to steroid injection [14] and provides satisfactory results in greater than 90% of patients [29]. Surgical treatment is required more often in patients with systemic diseases [29]. In patients with rheumatoid arthritis, preference is to excise a slip of the FDS tendon rather than release the A1 pulley to prevent exacerbation of ulnar drift [5, 14], and the entire annular pulley system should be preserved to prevent further ulnar drift of the fingers [14]. The radial digital nerve is at risk of iatrogenic injury during thumb trigger finger release due to its superficial location [5]. Minor complications include wound dehiscence, scar tenderness, and decreased range of motion [5]. Subsequent release or injection in the same or another digit is common following an initial trigger finger release [11]. Proximal interphalangeal joint pain results from long symptom duration and consequent joint pathology [21], and dorsal PIP tenderness is associated with higher and prolonged levels of postoperative pain after A1 pulley release [68]. PIP joint pain is incompletely resolved after A1 pulley release, leading to worse surgical outcomes than expected [21]. Physicians should consider the duration of preoperative symptoms and preoperative flexion contracture of the PIP joint when deciding timing of surgery [32]. Surgical management of pediatric trigger finger with isolated release of the A1 pulley has been associated with high recurrence rates [17], though a specific technique for pediatric trigger finger resulted in successful resolution of trigger digits in 91% of cases [59]. Factors associated with a worse outcome following a steroid injection have been identified and should be considered when choosing treatment [25]. Preoperative hypoglycemia increases infection risk after trigger finger injection and release [13].

Treatment

Non-Operative

Most triggering digits may be successfully treated by long-acting steroid injection into the flexor sheath [14], with 60% achieving success after one injection [19]. Repeat corticosteroid injections provided symptomatic relief for a year or more in 50% of patients [19]. Orthoses are effective for non-surgical management of pediatric and adult trigger finger using various orthotic options [44]. However, diabetic patients are generally less responsive to corticosteroid injection [5] and may be more refractory to nonoperative management [19]. Corticosteroid injections may elevate serum glucose levels for 5 days or more in patients with diabetes mellitus [19], and patients with unstable diabetes may be better treated without injection [19]. Factors associated with a worse outcome following a steroid injection were identified and should be considered when choosing the treatment of a trigger finger [25].

Operative

Indications: Surgical management of pediatric trigger finger with isolated release of the A1 pulley has been associated with high recurrence rates, necessitating exploration of other involved components of the flexor mechanism [17]. Surgical release is a short, safe, and effective procedure when performed by specialty trained hand surgeons, and it is the treatment of choice for a locked pediatric trigger thumb [24]. Surgical release of the A1 pulley is curative in digits refractory to steroid injection [14]. Management of diabetic trigger finger with immediate surgical release in the clinic is the most cost-effective treatment strategy, assuming a corticosteroid injection failure rate of at least 34% [27].

Surgical Approach / Technique: Open trigger finger release is generally a low-risk procedure, although there is potential for complications, some requiring reoperation [1]. Percutaneous trigger finger release can safely be performed on all digits, including the thumb, small fingers, and index fingers [4]. The thread trigger finger release technique was found to be safe and clinically effective, with all 34 digits showing resolved triggering and locking immediately following the procedure and no surgical complications observed [16]. Percutaneous release of the A1 pulley may be accomplished with a needle on the middle and ring fingers, especially if they actively lock [14]. The study confirms the efficacy and safety of percutaneous trigger finger release but shows no clinical advantage in using pre- or postoperative ultrasonography [12]. Surgical release should be done with a local block so that the cessation of triggering of a particular finger can be evaluated [19]. Some adjacent finger triggering may become obvious only after a given finger is released; both can be released at the same surgical setting [19]. Incomplete pulley release and damage to the flexor tendons and digital nerves remain a concern with limited exposure techniques [19].

Special Considerations: In patients with rheumatoid arthritis, preference is to excise a slip of the FDS tendon rather than to release the A1 pulley, because these patients are at risk for ulnar drift at the MCP joint, and with release of the A1 pulley there is a chance that this drift can be exacerbated [5]. In patients with rheumatoid arthritis, the entire annular pulley system should be preserved to prevent further ulnar drift of the fingers [14]. Triggering in rheumatoid patients is treated by tenosynovectomy and excision of one slip of the flexor digitorum superficialis [14]. In cases of trigger finger combined with Dupuytren's disease, an isolated opening of the pulley without touching the Dupuytren tissue followed by corticosteroid application in the area of the opened pulley is a strategy that may result in faster postoperative recovery and less progression of Dupuytren's disease [60].

Setting of Care: Patients who undergo open trigger finger release surgery in the clinic have complication rates similar to reported complication rates of surgery performed in the operating room [3]. Management of diabetic trigger finger with immediate surgical release in the clinic is the most cost-effective treatment strategy, assuming a corticosteroid injection failure rate of at least 34% [27]. Management of trigger finger with 2 steroid injections before surgery is the least costly treatment strategy [31].

Complications: Approximately 97% of patients have complete resolution after operative treatment [19]. Persistence of triggering is more common than recurrence after surgical release [19]. Minor complications of trigger finger release include wound dehiscence, scar tenderness, and decreased range of motion [5]. The radial digital nerve is at risk of iatrogenic injury during thumb trigger finger release, given its superficial location [5]. Preoperative corticosteroid injections are associated with a small but statistically significantly increased rate of deep infection after trigger finger release surgery [38]. Preoperative hypoglycemia increases infection risk after both trigger finger injection and release [5, 13]. Patients solely undergoing surgical release of their trigger finger had significantly higher odds and expedited rate of developing new-onset Dupuytren disease overall and undergoing subsequent treatment by fasciectomy compared with trigger fingers managed by other interventions [34].

Pain Management: Simultaneous steroid injection at the time of surgical release provides greater subjective improvement in the early period after percutaneous trigger finger release [2]. Local infiltration of Ketorolac as an adjunct in postoperative pain management has been shown to provide superior analgesia during finger movement within the initial 6 hours following trigger finger surgery, in comparison to oral NSAIDs [47]. Patients anticipate more pain than they experience with trigger finger injection [58].

Complications

Wound complications: Minor complications are prominent following trigger finger release, occurring in approximately 1 in 20 fingers as mild, transient adverse events [37]. These include wound dehiscence, scar tenderness, and decreased range of motion [5]. While major complications are unlikely, the rate of minor complications remains surprisingly high and is related mostly to wound complications or loss of finger range of motion [74]. Preoperative corticosteroid injections are associated with a small but statistically significantly increased rate of deep infection after surgery [38]. Specifically, patients undergoing open trigger release within 1 month of a corticosteroid injection face increased odds of developing a postoperative infection requiring surgical debridement [81].

Nerve palsy: The radial digital nerve is at risk of iatrogenic injury during thumb trigger finger release due to its superficial location [5]. Incomplete pulley release and damage to the digital nerves remain a concern with limited exposure techniques, particularly in the index finger and thumb [19].

Stiffness / Arthrofibrosis: Decreased range of motion is a recognized minor complication following the procedure [5]. Triggering may recur after operative release due to catching of the tendon on the palmar aponeurosis transverse fibers, though this usually resolves with time [19]. Occasionally, a partially lacerated flexor tendon at this level heals with a nodule sufficiently large to cause triggering [19].

Other Considerations: Open trigger finger release is generally a low-risk procedure, though complications requiring reoperation are possible [1]. Patients undergoing open release in the clinic have complication rates similar to those performed in the operating room [3]. Percutaneous release can be safely performed on all digits, including the thumb, small fingers, and index fingers [4], though ultrasound-assisted techniques raise questions regarding safety and efficacy despite confirming efficacy without clinical advantage from ultrasonography [8, 12]. The thread trigger finger release technique has been found safe and effective, with all 34 digits showing resolved triggering and locking immediately post-procedure and no surgical complications observed [16]. Subsequent release or injection in the same or another digit is common following an initial release [11]. In patients with rheumatoid arthritis, A1 pulley release carries a risk that ulnar drift at the MCP joint may be exacerbated [5]. Approximately 1 in 200 fingers require a second surgery after surgical release of the A1 pulley for idiopathic trigger finger [37].

Recovery

Light activity (weeks): Patients may typically resume desk work, driving, and light activities of daily living immediately following the procedure, as open trigger finger release is a low-risk intervention [1]. While structured preoperative instructions from a hand therapist do not significantly impact early postoperative recovery [35], the procedure itself allows for early mobilization. Complication rates for clinic-based surgery are comparable to those in the operating room, supporting safe early discharge [3]. Approximately 1 in 20 fingers experience a mild, transient adverse event after A1 pulley release [37].

Full activity (months): Surgical management effectively alleviates subjective and objective manifestations of trigger finger, serving as the benchmark procedure for restoring function [39]. Percutaneous release is safe for the thumb, index, middle, and ring fingers when the recommended technique is observed [9]. Simultaneous steroid injection at the time of surgical release provides greater subjective improvement in the early period following percutaneous release [2]. However, proximal interphalangeal joint pain resulting from long symptom duration and joint pathology may persist after A1 pulley release, leading to outcomes worse than expected [21].

Complete recovery / outcome plateau (months): Functional outcomes and scar quality do not differ significantly between transverse or longitudinal incisions [77]. Loss of motion remains reversible even after 21 years, with normal thumb function achievable even with very late presentation in pediatric trigger thumb [36]. Michigan Hand outcomes Questionnaire estimates can assist in interpreting clinical outcomes and assessing power in prospective trials [7]. Subsequent release or injection in the same or another digit remains a common occurrence following an initial trigger finger release [11].

Rehabilitation protocol: Postoperative thumb immobilization following A1 pulley release is not necessary for patients with trigger thumb, as it does not significantly impact functional outcomes or recurrence rates [76]. The manuscript provides a practical guide for clinicians to plan tailored rehabilitation management by matching traditional and novel techniques [10]. For pediatric trigger finger, isolated release of the A1 pulley is associated with high recurrence rates, necessitating exploration of other involved components of the flexor mechanism [17].

Functional milestones: Thirty-nine percent of second and third corticosteroid injections for trigger finger yield long-term relief [26]. About 1 in 200 fingers require a second surgery after surgical release of the A1 pulley for idiopathic trigger finger [37].

Key Evidence

  • [L3] Open trigger finger release is generally a low-risk procedure, although there is potential for complications, some requiring reoperation. (10.1007/s11552-014-9716-9)
  • [L1] Simultaneous steroid injection at the time of surgical release provides greater subjective improvement in the early period after percutaneous trigger finger release. (10.1177/1753193418813771)
  • [L4] Patients who undergo open trigger finger release surgery in the clinic have complication rates similar to reported complication rates of surgery performed in the operating room. (10.1016/j.jhsg.2022.01.008)
  • [L5] Based on our findings, percutaneous trigger finger release can safely be performed on all digits, including the thumb, small fingers, and index fingers. (10.1007/s11552-007-9069-8)
  • [L3] These MIC estimates can contribute to the interpretation of clinical outcomes following trigger finger release and for assessment of power in prospective trials. (10.1016/j.jht.2021.06.003)
  • [L5] While the clinical significance of these findings is unclear, it raises questions regarding the safety and efficacy of percutaneous trigger finger release, even when adding ultrasound guidance. (10.1007/s11552-008-9137-8)
  • [L4] It is a safe procedure for the thumb, index, middle, and ring fingers as long as the recommended technique is observed. (10.1016/j.jhsa.2010.06.006)
  • [L5] The manuscript aims to provide an updated practical guide for clinicians and surgeons reviewing the state-of-art of both the assessment and the treatments of patients with trigger finger to plan tailored rehabilitation management taking advantage of the matching of traditional and novel techniques. (10.1186/s12891-024-08192-5)
  • [L4] Subsequent release or injection in the same or another digit was common following an initial trigger finger release. (10.1016/j.jhsa.2025.02.009)
  • [L4] The study confirms the efficacy and safety of percutaneous trigger finger release but shows no clinical advantage in using pre- or postoperative ultrasonography. (10.1177/1753193413517992)
  • [L2] The thread trigger finger release technique was found to be safe and clinically effective, with all 34 digits showing resolved triggering and locking immediately following the procedure and no surgical complications observed. (10.1177/1753193418774497)
  • [L4] Surgical management of pediatric trigger finger with isolated release of the A1 pulley has been associated with high recurrence rates, necessitating exploration of other involved components of the flexor mechanism. (10.5435/jaaos-20-04-206)
  • [L4] Proximal interphalangeal joint pain in trigger finger patients results from long symptom duration and consequent joint pathology, and is incompletely resolved after A1 pulley release, leading to worse surgical outcomes than expected. (10.1177/1753193418809771)
  • [L4] Female patients presenting with their first trigger finger have the highest rate of long-term treatment success after a single corticosteroid injection. (10.2106/jbjs.n.00004)
  • [L4] Surgical release is a short, safe, and effective procedure when performed by specialty trained hand surgeons, and it is the treatment of choice for a locked pediatric trigger thumb. (10.1016/j.jhsa.2011.01.011)
  • [L3] Factors associated with a worse outcome following a steroid injection were identified and should be considered when choosing the treatment of a trigger finger. (10.1302/0301-620x.104b10.bjj-2022-0058.r3)
  • [L4] Thirty-nine percent of second and third corticosteroid injections for trigger finger yield long-term relief. (10.1016/j.jhsa.2017.02.001)
  • [L3] Management of diabetic trigger finger with immediate surgical release in the clinic is the most cost-effective treatment strategy, assuming a corticosteroid injection failure rate of at least 34%. (10.1016/j.jhsa.2016.08.007)
  • [L4] Pediatric trigger thumb responds universally to simple surgical release, whereas trigger fingers are more complex, often owing to systemic conditions or anatomical abnormalities, and require correspondingly more complex treatment. (10.1016/j.jhsa.2015.04.041)
  • [L2] Management of trigger finger with 2 steroid injections before surgery is the least costly treatment strategy. (10.1016/j.jhsa.2009.02.029)
  • [L4] Physicians should consider the duration of preoperative symptoms and preoperative flexion contracture of the PIP joint when deciding timing of surgery for trigger finger patients. (10.1016/j.jhsa.2018.06.023)
  • [L3] Major complications following trigger finger release are unlikely; however, minor complications are prominent. (10.1177/15589447221081869)
  • [L3] Patients solely undergoing surgical release of their trigger finger had significantly higher odds and expedited rate of developing new-onset Dupuytren disease overall and undergoing subsequent treatment by fasciectomy compared with trigger fingers managed by other interventions. (10.1177/15589447221077375)
  • [L2] Structured preoperative instructions from a hand therapist do not have a significant impact on early postoperative recovery after carpal tunnel and trigger finger surgeries. (10.1177/17531934251313763)
  • [Case_report] Loss of motion is still reversible even after 21 years, and normal thumb function can still be obtained with a very late presentation. (10.1177/15589447211052754)
  • [L4] This large retrospective series suggests that about 1 in 20 fingers will experience a mild, transient adverse event after surgical release of the A1 pulley for idiopathic trigger finger and that about 1 in 200 have a second surgery. (10.1016/j.jhsa.2012.05.014)
  • [L4] Preoperative corticosteroid injections are associated with a small but statistically significantly increased rate of deep infection after trigger finger release surgery. (10.1016/j.jhsa.2020.01.007)
  • [L5] Open surgical release of the A1 pulley effectively alleviates the subjective and objective manifestations of trigger finger and remains the benchmark procedure. (10.5435/jaaos-d-19-00614)
  • [L5] This commentary highlights that a single corticosteroid injection for trigger finger has a 45% long-term success rate, with success beyond two years likely predicting lasting symptom relief, though results vary by sex and number of affected digits. (10.2106/jbjs.n.00832)
  • [L1] Orthoses are effective for non-surgical management of pediatric and adult trigger finger using various orthotic options. (10.1016/j.jht.2023.05.016)
  • [L4] Comparing patients and hand surgeons, there were some differences in treatment preferences and perceived advantages and disadvantages regarding idiopathic trigger finger—differences that might be addressed by a decision aid. (10.1016/j.jhsa.2014.08.010)
  • [L1] Local infiltration of Ketorolac as an adjunct in postoperative pain management has been shown to provide superior analgesia during finger movement within the initial 6 hours following trigger finger surgery, in comparison to oral NSAIDs. (10.1186/s12891-024-07856-6)
  • [L4] The pulley system of the thumb is composed of 4 components, as opposed to the traditional view of only 3. (10.1016/j.jhsa.2012.08.005)
  • [L4] In contrast, surgical intervention has a high likelihood of restoring motion and function of the affected digit. (10.1016/j.jhsa.2023.03.015)
  • [L4] This is the first reported case of triggering pathology at the wrist to be treated with interventional radiological measures rather than open surgery and demonstrates the efficacy of the technique. (10.1177/1753193412453699)
  • [L1] Patients anticipate more pain than they experience with trigger finger injection. (10.1016/j.jhsa.2017.05.001)
  • [L4] This technique resulted in successful resolution of trigger digits in 91% of cases. (10.1016/j.jhsa.2007.05.031)
  • [L5] A1 pulley confluence varies on a digit-to-digit basis, with no observed confluence in the thumb and the most common confluence observed in the middle finger. (10.1016/j.jhsa.2022.02.011)
  • [L3] Patients with greater volar migration of the flexor tendons after CTR are at a higher risk of developing trigger finger. (10.1177/1753193413479506)
  • [L2] Using ultrasound guidance for corticosteroid injections is more effective for treating trigger fingers than the blinded method, leading to better results and a faster return to work in the early stages of treatment. (10.1186/s13018-023-03950-y)
  • [L2] Dorsal PIP tenderness is more common in trigger fingers than previously thought and is associated with higher and prolonged levels of postoperative pain after A1 pulley release. (10.1186/s12891-023-06130-5)
  • [L3] Cutoff values of 1.153 for adults and 1.362 for children were established to distinguish trigger thumb from healthy thumbs. (10.1186/s12891-023-06316-x)
  • [L3] This study provides new conclusive evidence that the repetitive power grip and flexion involved in rowing increase the prevalence of trigger finger. (10.1177/1558944720918321)
  • [L4] In the thumb, the flexor tendon and A1 pulley thickened significantly only after patients exhibited triggering. (10.1016/j.jhsa.2012.06.027)
  • [L4] Major complications occur infrequently, but the rate of minor complications was surprisingly high and related mostly to wound complications or loss of finger range of motion. (10.1016/j.jhsa.2009.12.040)
  • [L3] Postoperative thumb immobilization following A1 pulley release may not be necessary for patients with trigger thumb, as it does not significantly impact functional outcomes or recurrence rates. (10.1186/s13018-025-06203-2)
  • [L2] There were no significant differences in scar quality or improvement in patient-reported disability with transverse or longitudinal incisions for trigger finger release. (10.1177/1753193419859375)
  • [L2] Patients who undergo open trigger release within 1 month of a corticosteroid injection are at increased odds of developing a postoperative infection requiring surgical debridement. (10.1016/j.jhsa.2021.08.017)

See Also

References

[1] Risk Factors for Complications of Open Trigger Finger Release. HAND. 2014. DOI: 10.1007/s11552-014-9716-9

[2] Effects of simultaneous steroid injection after percutaneous trigger finger release: a randomized controlled trial. Journal of Hand Surgery (European Volume). 2018. DOI: 10.1177/1753193418813771

[3] Office-Based Open Trigger Finger Release Has a Low Complication Rate. Journal of Hand Surgery Global Online. 2022. DOI: 10.1016/j.jhsg.2022.01.008

[4] The Safety of Percutaneous Trigger Finger Release. HAND. 2007. DOI: 10.1007/s11552-007-9069-8

[5] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > 2. Flexor tendon injury > 3. Stenosing tenosynovitis (trigger finger).

[6] Miller S Review Of Orthopaedics. 2. Flexor tendon injury > 3. Stenosing tenosynovitis (trigger finger).

[7] Determining the Minimally Important Change of the Michigan Hand outcomes Questionnaire in patients undergoing trigger finger release. Journal of Hand Therapy. 2023. DOI: 10.1016/j.jht.2021.06.003

[8] Ultrasound-Assisted Percutaneous Trigger Finger Release: Is it Safe?. HAND. 2008. DOI: 10.1007/s11552-008-9137-8

[9] Anatomic Outcome of Percutaneous Release Among Patients With Trigger Finger. The Journal of Hand Surgery. 2010. DOI: 10.1016/j.jhsa.2010.06.006

[10] From diagnosis to rehabilitation of trigger finger: a narrative review. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-08192-5

[11] Incidence and Predictors of Subsequent Triggering Requiring Treatment After Trigger Finger Release. The Journal of Hand Surgery. 2026. DOI: 10.1016/j.jhsa.2025.02.009

[12] A study of 60 patients with percutaneous trigger finger releases: clinical and ultrasonographic findings. Journal of Hand Surgery (European Volume). 2014. DOI: 10.1177/1753193413517992

[13] Campbell S Operative Orthopaedics 4 Volume Set. EXCISION OF NECROTIC MUSCLES COMBINED WITH NEUROLYSIS OF MEDIAN AND ULNAR NERVES FOR SEVERE CONTRACTURE > REFERENCES > TRIGGER THUMB AND TRIGGER FINGER.

[14] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 9Hand Surgery > 2. Flexor Tenosynovitis (Trigger Finger and Trigger Thumb).

[15] Campbell S Operative Orthopaedics 4 Volume Set. EXCISION OF NECROTIC MUSCLES COMBINED WITH NEUROLYSIS OF MEDIAN AND ULNAR NERVES FOR SEVERE CONTRACTURE > TRIGGER FINGER AND THUMB > SURGICAL RELEASE OF TRIGGER FINGER.

[16] Minimally invasive thread trigger digit release: a preliminary report on 34 digits of the adult hands. Journal of Hand Surgery (European Volume). 2018. DOI: 10.1177/1753193418774497

[17] Management of Pediatric Trigger Thumb and Trigger Finger. Journal of the American Academy of Orthopaedic Surgeons. 2012. DOI: 10.5435/jaaos-20-04-206

[19] Campbell S Operative Orthopaedics 4 Volume Set. EXCISION OF NECROTIC MUSCLES COMBINED WITH NEUROLYSIS OF MEDIAN AND ULNAR NERVES FOR SEVERE CONTRACTURE > TRIGGER FINGER AND THUMB.

[21] Clinical significance of proximal interphalangeal joint pain in patients with trigger fingers. Journal of Hand Surgery (European Volume). 2018. DOI: 10.1177/1753193418809771

[23] Long-Term Outcomes Following a Single Corticosteroid Injection for Trigger Finger. Journal of Bone and Joint Surgery. 2014. DOI: 10.2106/jbjs.n.00004

[24] Surgical Release of the Pediatric Trigger Thumb. The Journal of Hand Surgery. 2011. DOI: 10.1016/j.jhsa.2011.01.011

[25] Factors associated with conversion to surgical release after a steroid injection in patients with a trigger finger. The Bone & Joint Journal. 2022. DOI: 10.1302/0301-620x.104b10.bjj-2022-0058.r3

[26] Long-Term Effectiveness of Repeat Corticosteroid Injections for Trigger Finger. The Journal of Hand Surgery. 2017. DOI: 10.1016/j.jhsa.2017.02.001

[27] Cost of Immediate Surgery Versus Non-operative Treatment for Trigger Finger in Diabetic Patients. The Journal of Hand Surgery. 2016. DOI: 10.1016/j.jhsa.2016.08.007

[29] Aaos Comprehensive Orthopaedic Review 3. Tendinopathy of the Hand and Wrist* > II. Trigger Finger.

[30] Pediatric Trigger Digits. The Journal of Hand Surgery. 2015. DOI: 10.1016/j.jhsa.2015.04.041

[31] Using Evidence to Minimize the Cost of Trigger Finger Care. The Journal of Hand Surgery. 2009. DOI: 10.1016/j.jhsa.2009.02.029

[32] Factors Causing Prolonged Postoperative Symptoms Despite Absence of Complications After A1 Pulley Release for Trigger Finger. The Journal of Hand Surgery. 2019. DOI: 10.1016/j.jhsa.2018.06.023

[33] Complications Following Endoscopic and Open Trigger Finger Release: A Retrospective Comparative Study. HAND. 2022. DOI: 10.1177/15589447221081869

[34] Surgical Trigger Finger Release Is Associated With New-Onset Dupuytren Contracture in the Short-Term Postoperative Period: A Matched Analysis. HAND. 2022. DOI: 10.1177/15589447221077375

[35] Preoperative hand therapy instructions do not improve short-term outcomes in carpal tunnel and trigger finger surgery. Journal of Hand Surgery (European Volume). 2025. DOI: 10.1177/17531934251313763

[36] Consequences of Untreated Pediatric Trigger Thumb: Case Report. HAND. 2021. DOI: 10.1177/15589447211052754

[37] Adverse Events of Open A1 Pulley Release for Idiopathic Trigger Finger. The Journal of Hand Surgery. 2012. DOI: 10.1016/j.jhsa.2012.05.014

[38] Risk of Infection in Trigger Finger Release Surgery Following Corticosteroid Injection. The Journal of Hand Surgery. 2020. DOI: 10.1016/j.jhsa.2020.01.007

[39] Current Concepts in the Management of Trigger Finger in Adults. Journal of the American Academy of Orthopaedic Surgeons. 2020. DOI: 10.5435/jaaos-d-19-00614

[41] Doc, Will This Injection Make My Trigger Finger Go Away?. Journal of Bone and Joint Surgery. 2014. DOI: 10.2106/jbjs.n.00832

[44] Orthotic intervention options to non-surgically manage adult and pediatric trigger finger: A systematic review. Journal of Hand Therapy. 2023. DOI: 10.1016/j.jht.2023.05.016

[45] Trigger Finger: Assessment of Surgeon and Patient Preferences and Priorities for Decision Making. The Journal of Hand Surgery. 2014. DOI: 10.1016/j.jhsa.2014.08.010

[47] Local ketorolac infiltration for postoperative pain in open trigger finger surgery: a randomized controlled trial. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-07856-6

[49] Varied Anatomy of the Thumb Pulley System: Implications for Successful Trigger Thumb Release. The Journal of Hand Surgery. 2012. DOI: 10.1016/j.jhsa.2012.08.005

[51] Campbell S Operative Orthopaedics 4 Volume Set. MULTIPLE Z-PLASTY RELEASE OF A CONGENITAL RING > TRIGGER FINGERS.

[52] Presentation and Management of the Pediatric Trigger Finger: A Multicenter Retrospective Cohort Study. The Journal of Hand Surgery. 2023. DOI: 10.1016/j.jhsa.2023.03.015

[53] Volar wrist ganglion presenting as trigger finger. Journal of Hand Surgery (European Volume). 2012. DOI: 10.1177/1753193412453699

[56] Dupuytren S Disease And Related Hyperproliferative Disorders. 31. The Influence of Dupuytren’s Disease on Trigger Fingers and Vice Versa > 31.5 Discussion.

[57] Dupuytren S Disease And Related Hyperproliferative Disorders. 31. The Influence of Dupuytren’s Disease on Trigger Fingers and Vice Versa > 31.5 Discussion > 31.5.1 Why Is DD Concurring with TF?.

[58] Needle-Free Jet Lidocaine Administration for Preinjection Anesthesia in Trigger Finger Injection: A Randomized Controlled Trial. The Journal of Hand Surgery. 2017. DOI: 10.1016/j.jhsa.2017.05.001

[59] Surgical Treatment of the Pediatric Trigger Finger. The Journal of Hand Surgery. 2007. DOI: 10.1016/j.jhsa.2007.05.031

[60] Dupuytren S Disease And Related Hyperproliferative Disorders. 31. The Influence of Dupuytren’s Disease on Trigger Fingers and Vice Versa > 31.5 Discussion > 31.5.3 Surgical Strategies and Recommendations.

[62] Defining the Digit-Specific Confluence of the A1 Pulley. The Journal of Hand Surgery. 2023. DOI: 10.1016/j.jhsa.2022.02.011

[63] The relationship of trigger finger and flexor tendon volar migration after carpal tunnel release. Journal of Hand Surgery (European Volume). 2013. DOI: 10.1177/1753193413479506

[64] Ultrasound guided versus blinded injection in trigger finger treatment: a prospective controlled study. Journal of Orthopaedic Surgery and Research. 2023. DOI: 10.1186/s13018-023-03950-y

[68] Dorsal proximal interphalangeal joint tenderness is associated with prolonged postoperative pain after A1 pulley release for trigger fingers. BMC Musculoskeletal Disorders. 2023. DOI: 10.1186/s12891-023-06130-5

[69] The cross-sectional area ratio of a specific part of the flexor pollicis longus tendon- a stable sonographic measurement for trigger thumb: a cross-sectional trial. BMC Musculoskeletal Disorders. 2023. DOI: 10.1186/s12891-023-06316-x

[71] Trigger Finger From Ocean Rowing: An Observational Study. HAND. 2020. DOI: 10.1177/1558944720918321

[72] Sonographic Appearance of the Flexor Tendon, Volar Plate, and A1 Pulley With Respect to the Severity of Trigger Finger. The Journal of Hand Surgery. 2012. DOI: 10.1016/j.jhsa.2012.06.027

[74] Complications of Open Trigger Finger Release. The Journal of Hand Surgery. 2010. DOI: 10.1016/j.jhsa.2009.12.040

[76] Pediatric trigger thumb treated with A1 pulley release with or without postoperative thumb immobilization: a retrospective study. Journal of Orthopaedic Surgery and Research. 2025. DOI: 10.1186/s13018-025-06203-2

[77] A prospective, randomized clinical trial of transverse versus longitudinal incisions for trigger finger release. Journal of Hand Surgery (European Volume). 2019. DOI: 10.1177/1753193419859375

[81] Temporal Relationship of Corticosteroid Injection and Open Release for Trigger Finger and Correlation With Postoperative Deep Infections. The Journal of Hand Surgery. 2022. DOI: 10.1016/j.jhsa.2021.08.017

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