SAEDNEWS: Trigger finger, also known as stenosing tenosynovitis, is a common condition caused by inflammation and narrowing of the tendon sheath. It can lead to stiffness, pain, and difficulty moving the affected finger. Depending on the severity, trigger finger can be treated with non-surgical methods or, when necessary, surgical intervention.
According to Saednews, To better understand why fingers become locked, it is important to first become familiar with the anatomy of the hand. The fingers are bent by flexor tendons that extend from the forearm to the fingertips. These tendons pass through structures called tendon sheaths, which produce synovial fluid to ensure smooth, friction-free tendon movement.
In the palm, the tendons pass beneath fibrous bands called pulleys, which keep the tendons close to the bones. The first pulley, located at the beginning of the tendon sheath, is known as the A1 pulley. In trigger finger, this pulley becomes thickened and narrowed, making it difficult for the tendon to glide smoothly underneath it.
The most common cause of a finger becoming locked is stenosing tenosynovitis, commonly known as trigger finger. In this condition, the tendon sheath—and particularly the A1 pulley—becomes inflamed and thickened for various reasons.
This thickening makes it difficult for the flexor tendon to pass smoothly beneath the pulley. The tendon may move through the narrowed area when the finger is bent, but it can become stuck when the finger is being straightened. In more advanced cases, the tendon itself may become thickened and develop a small lump or nodule, making it even harder for it to pass through the narrowed pulley.
Imagine a rope (the tendon) passing through a ring (the pulley). If the ring becomes narrower or the rope becomes thicker at one point, it becomes difficult for the rope to pass through.
With trigger finger:
When bending the finger:
The tendon may have difficulty passing beneath the pulley because of thickening or a nodule. With additional force, however, the tendon may eventually pass through.
When straightening the finger:
The thickened portion of the tendon can become trapped beneath the pulley, causing the finger to remain locked in a bent position. The finger may need to be straightened with the other hand or with additional force. This is often accompanied by a noticeable snap or click.
This snapping sensation is the reason the condition is called "trigger finger."
Symptoms of trigger finger can develop gradually and may be mild during the early stages. Common symptoms include:
Finger locking: The finger becomes stuck in a bent position and may require assistance from the other hand to straighten.
Clicking or snapping: A clicking or popping sensation or sound may occur when bending or straightening the finger.
Pain: Pain is usually felt in the palm at the base of the affected finger, particularly when gripping or applying pressure.
Morning stiffness: The fingers may feel especially stiff in the morning, making movement difficult.
Swelling and tenderness: A small lump or thickened area may be felt in the palm and can be sensitive to touch.
Limited movement: In advanced cases, the finger may remain completely locked and become difficult or impossible to straighten.
Although trigger finger can affect any finger, the ring finger and thumb are among the most commonly affected. The middle and index fingers can also be involved.
In some cases, several fingers may be affected at the same time, either on one hand or on both hands.
The exact cause of trigger finger is not always clear, but several factors can increase the risk of developing the condition.
Occupational activities:
People whose jobs involve activities such as prolonged computer use and typing, construction work, carpentry, gardening, playing musical instruments—especially string instruments—and operating vibrating tools may have a higher risk.
Everyday activities:
Frequent smartphone use, video gaming, or any activity that requires repeatedly gripping and releasing objects may also contribute to irritation of the tendon and its sheath.
Diabetes:
Diabetes is one of the strongest known risk factors. People with both type 1 and type 2 diabetes are more likely to develop trigger finger than the general population. This association may be related to changes in collagen structure and increased inflammation in tissues.
Inflammatory conditions:
Rheumatoid arthritis, gout, and hypothyroidism may increase the risk.
Carpal tunnel syndrome:
Trigger finger and carpal tunnel syndrome are often seen together and may share certain underlying risk factors.
Amyloidosis and sarcoidosis:
These less common conditions can cause abnormal material to accumulate in tissues and may also be associated with trigger finger.
Age:
Trigger finger is more common in people between the ages of 40 and 60.
Sex:
Women are reported to develop trigger finger more frequently than men.
Ethnicity:
Some studies have reported differences in the prevalence of trigger finger among different ethnic groups.
Pregnancy and breastfeeding:
Hormonal and physiological changes during pregnancy and breastfeeding may increase the risk.
Injury:
Direct trauma to the palm or fingers can cause inflammation and narrowing of the tendon sheath.
Previous surgery:
Previous hand surgery, including surgery for carpal tunnel syndrome, may occasionally be followed by the development of trigger finger.
Trigger finger is usually diagnosed based on the patient's medical history and a physical examination. Imaging is rarely necessary.
Medical history:
The doctor will ask about the symptoms, when they began, daily activities, underlying medical conditions such as diabetes or arthritis, and relevant medical history.
Physical examination:
The hand is carefully examined, including:
Palpation:
The doctor checks for a tendon nodule, swelling, or tenderness in the palm.
Movement assessment:
The patient may be asked to bend and straighten the fingers so the doctor can evaluate locking, clicking, and pain.
Range-of-motion assessment:
The extent of any limitation in finger movement is evaluated.
Imaging:
In rare or complicated cases, ultrasound or MRI may be used to examine the tendon and its sheath more closely. Ultrasound can help identify thickening of the A1 pulley and a tendon nodule.
Several other conditions can cause similar symptoms and may need to be ruled out.
Dupuytren's contracture:
This condition involves thickening and tightening of connective tissue in the palm, causing the fingers—usually the ring and little fingers—to gradually bend toward the palm. Unlike trigger finger, it typically does not cause sudden locking or clicking.
Arthritis:
Different types of arthritis, including osteoarthritis and rheumatoid arthritis, can cause pain, stiffness, and limited movement. However, sudden locking accompanied by a clicking sensation is less typical.
Infectious tenosynovitis:
This is a rare but serious infection of the tendon sheath. It can cause redness, swelling, warmth, and severe pain and requires prompt medical treatment.
Fracture or dislocation:
Bone and joint injuries can also restrict finger movement and should be considered, particularly after trauma.
Treatment for Fingers That Lock or Become Difficult to Straighten
Treatment for trigger finger depends on the severity of the condition, how long the symptoms have been present, and how well the patient responds to previous treatments. Options range from conservative measures to surgery.
These approaches are generally considered first-line treatments for mild to moderate cases.
Reducing or temporarily stopping activities that worsen symptoms can help. Using ergonomic equipment, such as a suitable keyboard and mouse, and modifying the way certain tasks are performed may also reduce strain on the hand.
A specialized splint may be used to keep the affected finger straight, particularly at night. This prevents the finger from bending during sleep and may reduce inflammation and morning stiffness.
A splint is commonly used for approximately 6 to 12 weeks, depending on the individual case and medical advice.
Cold compresses may help reduce pain and inflammation during an acute flare-up. Warm compresses can improve circulation and reduce stiffness, particularly when symptoms are more chronic.
Slow, gentle stretching exercises may help maintain or improve the finger's range of motion. These exercises should be performed appropriately and, when necessary, under the guidance of a doctor or physical therapist to avoid aggravating the condition.
Medications such as ibuprofen, naproxen, or diclofenac, taken orally or applied topically, may help reduce pain and inflammation.
These medications should be used carefully and according to medical advice, particularly in people with other medical conditions or those taking additional medications.
Specialized physical therapy techniques, including massage, ultrasound therapy, strengthening exercises, and stretching, may help improve hand function and mobility.
If conservative treatment does not provide adequate relief, a doctor may recommend a corticosteroid injection.
A corticosteroid injection is one of the most commonly used non-surgical treatments for trigger finger. A doctor uses a fine needle to inject corticosteroid medication around the tendon sheath near the A1 pulley.
Corticosteroids are powerful anti-inflammatory medications that can reduce inflammation and swelling. Improvement may occur within several days to a week.
Success rate:
Corticosteroid injections are effective in a substantial proportion of patients, with reported success rates varying depending on the severity of the condition and patient characteristics. The improvement may sometimes be temporary, and a repeat injection may be considered.
Possible side effects:
Side effects are uncommon but may include temporary pain at the injection site, thinning of the skin, localized skin discoloration, and, very rarely, tendon damage. In people with diabetes, corticosteroid injections can temporarily raise blood glucose levels.
Surgery may be recommended when non-surgical treatments—including corticosteroid injections—do not provide adequate improvement, or when the condition is severe and the finger remains significantly or completely locked.
Trigger finger surgery is usually performed as an outpatient procedure under local anesthesia. Two common approaches are used.
The surgeon makes a small incision, usually around 1–2 centimeters, in the palm over the A1 pulley. The thickened pulley is then carefully released to allow the tendon to move freely.
This procedure has a high success rate and is considered a reliable treatment for persistent trigger finger.
In this technique, the surgeon uses a specialized needle to release the A1 pulley through the skin without making a larger incision.
The procedure can result in a smaller wound and may allow a relatively quick recovery. However, it requires considerable technical expertise, and there may be a slightly greater risk of injury to nearby nerves or the tendon in certain cases.
After trigger finger surgery:
The hand should generally be kept elevated for several days to help reduce swelling.
The dressing should be kept clean and dry.
Sutures are commonly removed after approximately 10–14 days, depending on the surgical technique and healing.
Physical therapy may be recommended to restore range of motion and hand strength.
Many people can return to light activities within a few days, while a full return to strenuous activities may take approximately 4–6 weeks.
Complications are uncommon but may include:
Infection
Bleeding
Nerve injury, which may cause temporary or permanent numbness
Joint stiffness
Persistent symptoms or recurrence of trigger finger
Finger locking is most commonly associated with trigger finger, a condition in which thickening and narrowing around the A1 pulley interferes with the normal movement of a flexor tendon. Clicking, pain at the base of the finger, morning stiffness, and a finger that becomes stuck in a bent position are characteristic symptoms.
Mild cases may improve with activity modification, splinting, medication, and appropriate exercises. Corticosteroid injections can provide effective relief for many patients, while surgical release may be considered when symptoms persist or the finger becomes severely locked.
Because several other conditions can cause similar symptoms, persistent, painful, or progressively worsening finger locking should be evaluated by a qualified healthcare professional.
