Tinel’s test is a simple physical exam where a doctor taps over a nerve to check for damage or compression. If the tapping produces tingling, pins and needles, or an electric shock sensation that shoots along the path of the nerve, the result is considered positive. It’s most commonly used to evaluate carpal tunnel syndrome but applies to nerve problems throughout the body.
How the Test Is Performed
The examiner taps repeatedly over the spot where a nerve passes through a tight space, usually at the wrist. For carpal tunnel syndrome, the tapping targets the median nerve as it runs beneath the ligament on the palm side of the wrist. This percussion continues for up to 60 seconds, either with the examiner’s fingertips or with a reflex hammer. Using a reflex hammer instead of fingers increases the test’s sensitivity, making it more likely to detect a problem when one exists.
The test itself takes about a minute and doesn’t require any equipment beyond the examiner’s hands or a small hammer. You sit or stand while the examiner taps firmly but not painfully. There’s no preparation needed and no recovery time afterward.
What a Positive Result Feels Like
A positive Tinel’s sign means the tapping reproduces symptoms you’d recognize: tingling, a buzzing sensation, or a brief electric shock that radiates from the tap site into the fingers or hand (or foot, depending on the nerve being tested). The sensation follows the specific path of the affected nerve. For carpal tunnel syndrome, you’d feel it in the thumb, index finger, middle finger, and half of the ring finger, which is the territory the median nerve supplies.
If the tapping produces only local tenderness or discomfort at the tap site without that radiating tingling, the test is considered negative. The key distinction is whether the sensation travels along the nerve’s path rather than staying put.
Where It’s Used Beyond the Wrist
While carpal tunnel syndrome is the most familiar application, Tinel’s test works anywhere a nerve runs through a confined space and might be compressed or injured.
- Cubital tunnel syndrome: The examiner taps over the ulnar nerve at the inside of your elbow (the “funny bone” spot). Compression here causes tingling in the ring and pinky fingers.
- Tarsal tunnel syndrome: Tapping along the inside of the ankle targets the posterior tibial nerve, which can produce pain, tingling, or numbness in the foot when compressed.
The principle is identical in each location. Damaged or compressed nerve fibers become hypersensitive to mechanical stimulation, so tapping over them triggers an exaggerated electrical response that healthy nerves wouldn’t produce.
How Accurate Is It?
Tinel’s test is useful as a screening tool, but its accuracy varies considerably depending on the severity of the condition and the study measuring it. For carpal tunnel syndrome, sensitivity ranges from about 47% to 84% across different studies, meaning it catches somewhere between half and most true cases. Specificity, its ability to correctly identify people who don’t have the condition, ranges from about 56% to 80%.
The test performs much better at detecting moderate to severe nerve compression than mild cases. In a study of 449 symptomatic hands, Tinel’s sign was positive in only 34% of mild carpal tunnel cases but in 88% of severe cases. This makes sense: the more damaged the nerve, the more reactive it becomes to tapping.
One consistent strength is the test’s positive predictive value, which reached 85% to 92% in multiple studies. That means when the test is positive, there’s a high probability you actually have the condition. The flip side is that a negative result is less reassuring. The negative predictive value was low, ranging from 11% to 57%, so a normal Tinel’s test doesn’t reliably rule out nerve compression.
How It Compares to the Phalen Test
Phalen’s test is the other common bedside exam for carpal tunnel syndrome. Instead of tapping, you hold your wrists in a fully bent position (flexed downward) for up to 60 seconds. If this sustained pressure on the nerve reproduces tingling in the same median nerve distribution, the test is positive.
The two tests have complementary strengths. Tinel’s test is more sensitive, meaning it catches more true cases: 74% versus about 50% for the Phalen test in one large study, and 59% versus 70% in a separate meta-analysis. Phalen’s test tends to be more specific, correctly identifying unaffected hands about 89% of the time compared to 72% for Tinel’s. Because each test misses different cases, clinicians often perform both during the same exam. Neither one alone is definitive, and nerve conduction studies remain the gold standard for confirming a diagnosis when results are unclear.
Tracking Nerve Recovery
Tinel’s test has a second, less well-known purpose: monitoring nerve regeneration after an injury or surgical repair. When a nerve is healing, the growing nerve fibers at the leading edge are especially sensitive to tapping. By testing along the length of the nerve over weeks and months, clinicians can track where that hypersensitive point has migrated. As the nerve regrows, the positive Tinel’s sign moves farther from the injury site and closer to the fingertips or toes. This progression confirms that regeneration is happening and gives a rough sense of its speed, since peripheral nerves typically regrow at a slow, predictable rate.
In this context, a positive Tinel’s sign is actually a good thing. It means new nerve fibers are advancing. A Tinel’s sign that stops moving, or one that never appears after nerve repair, can signal that regeneration has stalled.