Trigger Finger
Upper LimbOverview
Trigger finger is a common condition affecting the flexor tendons of the hand, characterized by inflammation and thickening of the tendon sheath causing mechanical catching and locking during finger flexion and extension. The condition typically presents with pain, clicking, or locking of the affected digit, most commonly affecting the thumb, middle, and ring fingers. It ranges from mild clicking to severe locking requiring manual extension of the finger.
Pathophysiology
The pathophysiology involves chronic inflammation and fibrosis of the flexor tendon sheath (A1 pulley), causing the tendon to thicken and develop nodules. As the finger flexes, the enlarged tendon passes through the narrowed pulley with difficulty, creating a catching sensation. Repetitive gripping, sustained finger flexion, and microtrauma lead to synovial inflammation, collagen deposition, and eventual mechanical obstruction. This creates a cycle of inflammation, scarring, and further restriction of tendon gliding within the sheath.
Typical Presentation
Site
Palmar aspect of the metacarpophalangeal joint (MCP) of affected digit; thumb, index, middle, ring, or little finger; often bilateral in 10-30% of cases
Quality
Catching, clicking, or locking sensation during finger movement; morning stiffness; sharp pain at the MCP joint level; sensation of mechanical block
Intensity
Mild clicking (stage 1) to complete locking requiring manual extension (stage 4); symptoms typically worse in morning and with gripping activities
Aggravating
Gripping activities, repetitive finger flexion, sustained finger positions, cold weather, morning stiffness, forceful grasping, fine motor tasks
Relieving
Rest, gentle passive extension, massage of the palm, anti-inflammatory measures, ice application, avoiding aggravating activities
Associated
Morning swelling at MCP joint, weakness in grip strength, nocturnal symptoms, referred pain to palm and distal fingers, callus formation on palm, difficulty with daily activities (writing, buttoning, typing)
Orthopaedic Tests
Flexion contracture test
Procedure
Ask the patient to make a full fist and then straighten the affected finger. If it stays bent, gently try to straighten it passively and note whether it is locked (releases with a snap) or has a fixed contracture, usually at the PIP joint.
Positive Finding
The finger stays flexed and cannot be straightened actively, straightens only passively with a painful snap, or has a fixed loss of PIP extension.
Interpretation
A locked finger or a fixed PIP contracture means more advanced triggering. It also helps separate trigger finger from other causes of a bent finger, such as Dupuytren's contracture or a central slip (boutonnière) injury, which do not snap.
Triggering phenomenon test
Procedure
Place a fingertip over the A1 pulley (at the distal palmar crease for the fingers, at the MCP crease for the thumb) while the patient slowly makes a full fist and then opens the hand, several times.
Positive Finding
A palpable click or catch, or the finger sticking in flexion and then snapping straight.
Interpretation
Triggering is the defining sign of trigger finger. It may not appear at every visit, so ask whether it is worse in the morning and ask the patient to show you. The reference previously shown for this test could not be matched to any published paper and has been withdrawn. A literature search (Europe PMC, September 2026) found no study reporting the diagnostic accuracy of this test, so no figure is shown.
Palpation of tendon nodule
Procedure
Palpate over the A1 pulley at the base of the affected digit on the palmar side while the patient gently bends and straightens the finger.
Positive Finding
Tenderness over the A1 pulley, often with a small nodule that moves with the tendon.
Interpretation
Supports trigger finger, especially when a moving nodule can be felt to catch. Tenderness alone, without catching, can occur in early disease.
Morning stiffness and symptom history
Procedure
Ask about stiffness, catching or locking of the finger, what time of day it is worst, and whether the patient has to use the other hand to straighten it. Also ask about diabetes, rheumatoid arthritis and repetitive gripping.
Positive Finding
Catching or locking that is usually worst in the morning and eases with use, with pain at the base of the finger in the palm.
Interpretation
Supports trigger finger. Prolonged morning stiffness in several joints, or swelling of the joints rather than the tendon, points instead towards an inflammatory arthritis.
Pain with resisted flexion at PIP joint (Flexor Digitorum Superficialis test)
Procedure
Hold the patient's other fingers fully straight, then ask them to bend the PIP joint of the affected finger against your resistance.
Positive Finding
Pain at the base of the finger over the A1 pulley during resisted flexion.
Interpretation
Suggests flexor tendon sheath irritation. This is not a recognised diagnostic test for trigger finger; triggering on active movement remains the key sign.
Ultrasound-guided clinical correlation
Procedure
High-frequency ultrasound over the A1 pulley in long and short axis, with dynamic scanning while the patient bends and straightens the finger.
Positive Finding
Thickening of the A1 pulley, swelling or a nodule of the flexor tendon at the pulley, and catching of the tendon seen during movement.
Interpretation
Not needed to diagnose a typical case, which is clinical. Ultrasound helps when the diagnosis is unclear and is commonly used to guide injection. The reference previously shown for this test could not be matched to any published paper and has been withdrawn. A literature search (Europe PMC, September 2026) found no diagnostic accuracy study of ultrasound for trigger finger, so no figure is shown.
⚠ Red Flags
- •Sudden onset with significant trauma or laceration suggesting tendon rupture
- •Signs of infection (warmth, erythema, purulent discharge) suggesting infectious tenosynovitis
- •Rapid progression with complete loss of finger extension suggesting advanced pathology
- •Systemic symptoms (fever, malaise) suggesting inflammatory arthropathy or infection
- •Signs of vascular compromise (color change, coolness, numbness) suggesting circulatory problem
- •Multiple joint involvement with constitutional symptoms suggesting rheumatoid arthritis or other systemic condition
⚡ Yellow Flags
- •Occupational or recreational activities requiring intensive gripping creating perpetuating mechanical stress
- •Catastrophizing about hand function affecting work capacity or self-image
- •Belief that condition will worsen without intervention creating health anxiety
- •Secondary gain from avoiding work or activities due to hand dysfunction
- •Excessive focus on symptom severity without engagement in conservative management
- •Social isolation due to inability to perform meaningful activities
Osteopathic Techniques
Region
Forearm flexor compartment and flexor digitorum superficialis/profundus
Technique
Rationale
Direct soft tissue mobilization to the flexor muscle belly reduces tension in the muscle-tendon unit, decreases proximal pull on the A1 pulley, and improves tendon gliding mechanics. Addresses myofascial restrictions that contribute to increased tension within the flexor sheath.
Region
A1 pulley (palmar surface at MCP joint crease)
Technique
Rationale
Gentle cross-friction massage over the A1 pulley helps modulate inflammation, promote tendon gliding, reduce scar tissue formation, and improve proprioceptive feedback. Should be performed cautiously to avoid exacerbating inflammation.
Region
Wrist joint and carpal bones
Technique
Rationale
Gentle articulation of the wrist improves the length-tension relationship of the flexor tendons, reduces mechanical compression at the wrist level, and enhances overall hand circulation. Proper wrist mechanics reduce compensatory stress on finger flexors.
Region
Hand intrinsic muscles and deep palmar fascia
Technique
Rationale
Releasing tension in hand intrinsics and addressing fascial restrictions in the palm improves overall hand mobility, reduces local inflammatory response, and enhances tendon-sheath relationship through improved soft tissue elasticity.
Region
Lymphatic drainage pathways of hand and forearm
Technique
Rationale
Gentle lymphatic drainage techniques enhance removal of inflammatory mediators and metabolic waste products from the affected tendon sheath, reduce local edema, and promote tissue healing through improved fluid dynamics.
Rehabilitation Exercises
Gentle Finger Flexion and Extension Gliding
Forearm Flexor Muscle Stretch with Wrist Extension
Differential Tendon Gliding Exercises (Hook, Straight, Full Fist)
Intrinsic Hand Muscle Activation (Lumbrical Exercises)
Pronator and Supinator Muscle Stretching
Gentle Wrist Mobilization in Multiple Planes
Progressive Grip Strengthening with Therapy Putty
Ergonomic Hand and Wrist Positioning Awareness
Forearm Flexor Eccentric Loading Exercises
Finger Circumduction and Multi-Directional Movement
Deep Palm and Hand Intrinsic Self-Massage Release
Finger Abduction and Adduction Resistance Exercises
Referral Criteria
- •Failure to improve with conservative management after 6-12 weeks indicating need for corticosteroid injection or surgical intervention
- •Progression to complete locking requiring manual extension suggesting advanced stage requiring specialist assessment
- •Severe functional impairment affecting work or activities of daily living requiring specialist hand therapy or surgery
- •Suspected infection or inflammatory arthropathy (rheumatoid arthritis, diabetes-related stiffness) requiring medical investigation
- •Recurrent symptoms after steroid injection suggesting need for surgical consultation (A1 pulley release)
- •Multiple finger involvement with systemic symptoms suggesting rheumatological condition requiring rheumatology referral
- •Failure of mechanical treatment combined with progressive neurological symptoms suggesting nerve compression
- •Patient desire for definitive surgical treatment after appropriate conservative management trial