TRIGGER FINGER

What is trigger finger?

Trigger finger is a "snapping" condition of any of the digits of the hand when opened or closed. Trigger finger is medically termed stenosing tenosynovitis.

What are symptoms of trigger finger?symptoms of trigger finger may progress from mild to severe and

include: Finger stiffness, particularly in the morning A popping or clicking sensation as you move your finger Finger locked in a bent position, which you are unable to straighten,

which suddenly pops straight Locking or catching during active flexion-extension activity (Passive

manipulation may be needed to extend the digit in the later stages.) Stiff digit, especially in long-standing or neglected cases Pain over the distal palm Pain radiating along the digit

Trigger finger more commonly occurs in your dominant hand, and most often affects your thumb or your middle or ring finger. More than one finger may be affected at a time, and both hands might be involved. Triggering is usually more pronounced in the morning, while firmly grasping an object or when straightening your finger.

Signs of TF are as follows:

Triggering on active or passive extension by the patient

Palpable snapping sensation or crepitus over the A1 pulley

Tenderness over the A1 pulley, Palpable nodule in the line of the FDS, just distal to

the MCP joint in the palm. Tenderness or a bump (nodule) at the base of the affected finger

Fixed-flexion deformity in late presentations, especially in the proximal interphalangeal (PIP) joint

Evidence of associated conditions (eg, RA, gout) Early signs of triggering in other digits (may be

bilateral)

Causes

Trauma/local Systemic causes of TF are collagen-vascular diseases, including RA, DM, psoriatic arthritis,

amyloidosis, hypothyroidism, sarcoidosis, and pigmented villonodular synovitis. Septic causes of TF are secondary infections (eg, tuberculosis).Idiopathic The etiology of TF is unknown or uncertain; suspect nodule or pulley morphology change. Other causes that can simulate locking include the following:

Collateral ligaments of the metacarpophalangeal (MCP) joint catch on a bony prominence on the side of the metatarsal head (osteophyte).

Localized swelling in the flexor digitorum profundus (FDP) gets entrapped at the decussation of the FDS.

A partially lacerated flexor tendon catches against the A1 pulley or the FDS decussation. A nodule in the FDS catches against the A3 pulley. Locking is simulated by abnormal sesamoids. A loose body is present in the MCP joint. Snapping or subluxation of the extensor digitorum communis (EPC) occurs.

StagingGreen's classification of triggering is used only for

clinical grading and documentation. No correlation is established between the grading scheme and the outcome following injection therapy.

Grade I (pretriggering) - Pain; history of catching that is not demonstrable on clinical examination; tenderness over the A1 pulley

Grade II (active) - Demonstrable catching, but with the ability to actively extend the digit maintained 

Grade III (passive) - Demonstrable locking in which passive extension is required (grade III A) or in which the patient is unable to actively flex (grade III B)

Grade IV (contracture) - Demonstrable catching, with a fixed flexion contracture of the PIP joint

Risk factors

Factors that put you at risk of developing trigger finger include:

Repetitious gripping. If you routinely grip an item — such as a power tool or musical instrument — for extended periods of time, you may be more prone to the development of a trigger finger.

Certain health problems. You're also at greater risk if you have certain medical conditions, including rheumatoid arthritis, diabetes, hypothyroidism, amyloidosis and certain infections, such as tuberculosis.

Your sex. Trigger finger is more common in women.

Treatment

Treatment of mild casesFor mild or infrequent symptoms, these approaches may be effective:

Rest. You may notice improvement simply by resting the affected hand for four to six weeks. To prevent the overuse of your affected finger, your doctor may also suggest you change or curtail work or personal activities that require repeated gripping actions.

Splinting. Your doctor may have you wear a splint to keep the affected finger in an extended position for up to six weeks. The splint helps to rest the joint. Splinting also helps prevent you from curling your fingers into a fist while sleeping, which can make it painful to move your fingers in the morning.

Finger exercises. Your doctor may also suggest that you perform gentle exercises with the affected finger. This can help you to maintain mobility in your finger.

Avoiding repetitive gripping. For at least three to four weeks, avoid activities that require repetitive gripping, repeated grasping or the prolonged use of vibrating machinery.

Soaking in warm water. Placing your affected hand in warm water, especially in the morning, may reduce the severity of the catching sensation during the day. If this helps, you can repeat the soaking several times throughout the day.

Massage. Massaging your affected fingers may feel good and help relieve your pain, but it won't affect the inflammation.

Treatment of serious cases

For more-serious symptoms, your doctor may recommend other approaches, including:

Nonsteroidal anti-inflammatory drugs (NSAIDs). Medications such as nonsteroidal anti-inflammatory drugs — ibuprofen (Advil, Motrin, others), for example — may relieve the inflammation and swelling that led to the constriction of the tendon sheath and trapping of the tendon, and can relieve the pain associated with trigger finger.

Steroids. An injection of a steroid medication, such as cortisone, near or into the tendon sheath also can be used to reduce inflammation of the sheath. This treatment is most effective if given soon after signs and symptoms begin. Injections can be repeated if necessary, though repeated injections may not be as effective as the initial injection. Steroid injections may not be as effective in people with other medical conditions, such as rheumatoid arthritis or diabetes.

Percutaneous trigger finger release. In this procedure, which is performed under local anesthesia, doctors use a needle to release the locked finger. This procedure is most effective for the index, middle and ring fingers.

Surgery. Though less common than other treatments, surgical release of the tendon may be necessary for troublesome locking that doesn't respond to other treatments.

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