Trigger thumb, also known as stenosing tenosynovitis, causes a finger or thumb to get stuck in a bent position, often with a popping sensation when straightened. This occurs due to inflammation and narrowing of the tendon sheath. Splinting is a common and effective non-surgical treatment.
Understanding Trigger Thumb and Splinting’s Role
Trigger thumb occurs when the flexor pollicis longus tendon or its surrounding sheath becomes inflamed and swollen, preventing smooth gliding through the A1 pulley at the thumb’s base. This causes the thumb to “catch” or “lock” when extending.
Splinting alleviates symptoms by immobilizing the affected joint, typically the metacarpophalangeal (MP) or interphalangeal (IP) joint. Restricting movement reduces friction and irritation on the inflamed tendon, allowing swelling to decrease and the tendon to heal.
Key Features of Effective Trigger Thumb Splints
Effective splints restrict movement of the affected thumb joint while allowing other fingers to function. One common type is the thumb spica splint, which extends from the forearm, immobilizing the wrist and the metacarpophalangeal (MP) joint of the thumb. These splints provide comprehensive rest to the thumb’s tendons.
Alternatively, some splints focus solely on immobilizing the interphalangeal (IP) joint of the thumb. These designs are generally smaller and less restrictive than thumb spica splints, offering targeted support. Their compact nature allows for greater hand mobility.
Splints are constructed from various materials. Thermoplastic splints can be custom-molded by a healthcare professional for a precise fit, ensuring optimal immobilization and comfort. Neoprene or fabric splints offer flexibility and breathability for comfortable, prolonged wear.
Design considerations include adjustability for a snug fit without impeding circulation, and breathability to prevent skin irritation. Designs also ensure other fingers remain free, enabling daily tasks.
Selecting the Right Splint
Choosing a splint depends on several factors. The severity of the condition, including the frequency and intensity of catching or locking, influences the required immobilization level. More persistent locking may necessitate a rigid or comprehensive splint.
The triggering location also guides splint selection. For issues at the thumb’s base (MP joint), a thumb spica splint immobilizing the wrist and MP joint is effective. If the problem is at the interphalangeal (IP) joint, a smaller splint targeting only that joint may be suitable.
Daily activities and lifestyle also play a role. A bulkier splint might hinder manual tasks, while a streamlined design allows for light activities. Comfort and fit are important; a splint should be snug enough for support without causing discomfort or restricting blood flow.
Both off-the-shelf and custom-made splints are available. Custom splints offer a precise fit, enhancing effectiveness and comfort. Consulting a healthcare professional, such as a hand therapist or physician, is advisable for an accurate diagnosis and personalized recommendation.
Proper Use and Expected Outcomes
Consistent wearing is important for successful treatment. Healthcare providers often recommend wearing the splint at night to prevent unconscious thumb movement. Wearing it during activities that aggravate symptoms, like repetitive gripping, can also be beneficial.
Maintain splint cleanliness for skin health and hygiene. Most splints can be gently cleaned with mild soap and water, then air dried. Proper care extends the splint’s life and prevents skin irritation.
Improvement from splinting typically occurs gradually, with symptom relief within several weeks to a few months. Tendon healing is slow, so patience and consistent splint use are necessary. Continued dedication to the splinting regimen is often associated with positive outcomes.
If symptoms persist or worsen despite consistent splint use over several weeks, consult a healthcare professional. Persistent pain, increased locking, or lack of improvement may indicate a need for other treatment options, such as corticosteroid injections or surgical intervention to release the A1 pulley.