What is the pathophysiology and treatment of trigger finger (stenosing tenosynovitis)?

From the Guidelines

Trigger finger, also known as stenosing tenosynovitis, is primarily treated with conservative measures, including rest, splinting, and anti-inflammatory medications, with corticosteroid injections and surgical release considered for moderate to severe cases or when conservative measures fail, as suggested by recent guidelines such as the 2023 update from the American College of Radiology 1. The pathophysiology of trigger finger involves inflammation and thickening of the flexor tendon sheath, particularly at the A1 pulley, leading to catching or locking of the tendon as it moves through the pulley system. This results in the characteristic triggering or locking of the finger. Key treatment strategies include:

• Rest and activity modification to reduce strain on the affected tendon
• NSAIDs like ibuprofen 400-600mg three times daily for 1-2 weeks to reduce inflammation
• Night splinting of the affected finger for 6-8 weeks to maintain extension and reduce contracture For moderate to severe cases, or if conservative measures fail after 4-6 weeks, consider:
• Corticosteroid injection into the tendon sheath, such as triamcinolone 10mg/mL, 1mL injection, which can be repeated after 4-6 weeks if symptoms persist
• Surgical release of the A1 pulley for refractory cases, as it provides a definitive solution to the mechanical obstruction causing the trigger finger Additional advice to patients includes:
• Applying ice to the affected area for 10-15 minutes, 2-3 times daily, to reduce inflammation
• Performing gentle stretching exercises of the affected finger to maintain range of motion
• Avoiding repetitive gripping or activities that exacerbate symptoms
• Ensuring good glycemic control if diabetes is present, as it can contribute to the development of trigger finger, as highlighted in the context of chronic hand and wrist pain management 1.

From the Research

Pathophysiology of Trigger Finger

• Trigger finger is a common hand condition that occurs when movement of a finger flexor tendon through the first annular (A1) pulley is impaired by degeneration, inflammation, and swelling, causing pain and restricted movement of the affected finger 2
• It is thought to be caused by inflammation and subsequent narrowing of the A1 pulley, which causes pain, clicking, catching, and loss of motion of the affected finger 3
• Although it can occur in anyone, it is seen more frequently in the diabetic population and in women, typically in the fifth to sixth decade of life 3

Treatment of Trigger Finger

• Treatment modalities include:
  • Conservative treatments: NSAIDs, hand splints, corticosteroid injections, physical therapies 4, 2, 3
  • Surgical treatments: percutaneous or open surgery, percutaneous release of the A1 pulley 4, 5
• Physical therapies, such as external shock wave therapy (ESWT) and ultrasound therapy (UST), have been shown to be effective in reducing pain and trigger severity, and improving functional level and quality of life 4
• Corticosteroid injection is an effective treatment for trigger finger, with symptoms and signs resolving in 61% of cases after a single injection, and recurrent episodes being effectively re-treated with injection 6
• Percutaneous release of the A1 pulley (PTFR) has been shown to be a effective treatment for trigger finger, with patients in the PTFR group having greater recovery and satisfaction level, and lower recurrence rate and pain, compared to corticosteroid injection 5
• Non-steroidal anti-inflammatory drugs (NSAIDs) may offer little to no benefit over glucocorticoid injection in the treatment of trigger finger, based on low- to very low-certainty evidence from two trials 2