A small splint worn on the middle knuckle of the affected finger is the most effective and comfortable option for treating trigger finger. Specifically, a PIP joint splint (worn at the middle knuckle) outperforms splints placed at other joints, with research showing success rates up to 97% for mild to moderate cases. The best-studied off-the-shelf option is the Oval-8 finger splint, though custom-made alternatives work just as well.
Why Splinting Works for Trigger Finger
Trigger finger happens when the tendon that bends your finger gets irritated where it passes through a tight tunnel near the base of the finger. Every time you curl and straighten your finger, that tendon slides back and forth through the tunnel. When the tendon or its surrounding tissue swells, it catches on the tunnel’s edge, causing the clicking, locking, or snapping sensation.
A splint works by limiting how much the tendon moves through that trouble spot. Less movement means less friction, which gives inflamed tissue time to calm down and shrink back to normal size. This is why splinting is recommended as a first-line treatment alongside activity modification and stretching exercises, before considering injections or surgery.
PIP Splints vs. MCP Splints
There are two main joint positions where a trigger finger splint can be placed: the MCP joint (the large knuckle where your finger meets your palm) and the PIP joint (the middle knuckle). Research comparing the two finds the PIP splint is the better choice for most people.
In a head-to-head study, a PIP splint produced greater pain reduction and better functional improvement scores than an MCP splint. But the real advantage was comfort. Patients found the PIP splint less noticeable and less restrictive, which meant they actually wore it. The PIP group averaged 13.3 hours of wear per day compared to just 9.6 hours for the MCP group. That difference matters enormously, because a splint only works when it’s on your finger.
MCP splints do have one advantage: when people committed to wearing them, a higher percentage hit 18 or more hours per day of use. An MCP splint covers more of the hand and restricts more movement, which can be helpful for severe cases where the finger is locking frequently. But for most people with mild to moderate triggering, the PIP splint’s smaller profile and better compliance make it the stronger choice.
The Oval-8: Best Off-the-Shelf Option
The Oval-8 is a slim, figure-eight shaped plastic ring that fits over the middle knuckle. It’s the most studied commercially available PIP splint for trigger finger and has several practical advantages. It comes in sizes 2 through 15, so there’s a good fit for most fingers. Each splint actually fits two sizes depending on which end you slide on first, since the angled band creates a tighter or looser fit. They’re inexpensive, easy to order, and don’t require a clinic visit to fabricate.
To find your size, measure around the middle knuckle of the affected finger. A jeweler’s wide ring gauge works well for this. The fit should be snug but not tight. If you’re wearing the splint over a bandage or gel sleeve, go at least one size up. Keep in mind that swelling and temperature changes throughout the day can affect fit, so having a second size on hand is a good idea.
Custom-Made Splints
A hand therapist can fabricate a custom splint from thermoplastic material in under 30 minutes during a clinic visit. These offer a precise, low-profile fit tailored to your specific hand size and finger shape. In one study, 29 out of 30 patients were satisfied with a custom-made adjustable PIP splint, and the group showed significant functional improvement over six weeks.
Custom splints make the most sense if your fingers are unusually large or small, if you’ve tried an off-the-shelf option and couldn’t get a comfortable fit, or if you need the splint to accommodate other hand issues. The trade-off is cost and access: you’ll need a referral to a hand therapist, and the splint itself will be more expensive than a $10 to $15 Oval-8.
How Long to Wear a Splint
A typical splinting protocol runs about six weeks, though the range in studies is three to nine weeks depending on severity. The goal is to wear the splint as many hours per day as you can tolerate. Night wear is especially important because many people unconsciously curl their fingers tightly during sleep, which is why trigger finger symptoms are often worst in the morning. Keeping the finger in a slightly extended position overnight reduces that overnight tendon irritation.
You don’t necessarily need to wear the splint around the clock. Many people find that wearing it at night and during activities that aggravate their symptoms (repetitive gripping, using tools, typing) provides enough relief. The key is consistency over the full treatment period. Stopping after two weeks because symptoms improve often leads to a return of catching and pain.
Splinting vs. Steroid Injections
If you’re weighing whether to try a splint or go straight for a cortisone shot, the evidence may surprise you. A study that followed patients for a full year found no clinically important differences between splinting alone and steroid injection alone in terms of pain reduction, symptom improvement, or functional recovery. No patients in any group experienced treatment failure at 6 or 12 weeks, and outcomes at 52 weeks were comparable across all groups.
This is why current clinical guidelines recommend splinting as the initial treatment for trigger finger in adults. It carries no injection-related risks (tendon weakening, skin changes, blood sugar spikes in people with diabetes) and costs significantly less. If splinting doesn’t resolve the problem after a full course, steroid injection or a combination approach is a reasonable next step.
When Splinting May Not Be Enough
Splinting works best for trigger finger that’s in its earlier stages, where you’re experiencing pain, clicking, or occasional catching but the finger still straightens on its own. The more severe the condition, the less likely splinting alone will resolve it. A finger that locks in a bent position and has to be manually pried open, or one that has become permanently fixed in a bent posture, typically needs injection or a minor surgical release procedure.
Other factors that can reduce splinting success include having had symptoms for many months before starting treatment, having multiple trigger fingers at once, and certain underlying conditions like diabetes or rheumatoid arthritis that contribute to ongoing tendon inflammation. Even in these situations, splinting can still reduce pain and improve function, but it’s less likely to fully eliminate the triggering on its own.