7 Iunie 2026

    Carpal tunnel syndrome: symptoms, causes and diagnosis

    Author: Dr. Alexandru Grecu — Senior Orthopedic and Trauma Surgeon

    Medically reviewed by Dr. Alexandru Florian Grecu, Senior Orthopedic Surgeon · Published: 7 iunie 2026 · Updated: June 7, 2026

    Short answer: Carpal tunnel syndrome appears when the median nerve is compressed at the wrist. The typical sign: numbness and tingling in the thumb, index, middle and half of the ring finger, mostly at night. The cause is often a combination of factors — repetitive activity, pregnancy, hypothyroidism, diabetes — or remains idiopathic. The diagnosis starts from the clinical examination, with the Phalen test and Tinel's sign, and is confirmed with a nerve conduction study (EMG). In mild and moderate forms, treatment starts conservatively: a night splint, activity adjustment, sometimes an injection.

    What the carpal tunnel is

    At the wrist, the finger tendons and the median nerve pass through a narrow canal — the carpal tunnel — covered by a strong ligament. When pressure in this space rises, the median nerve is compressed. From there, in order: first numbness and tingling, then, if the pressure persists, weakness.

    The median nerve carries sensation from the thumb, index, middle and half of the ring finger. The pattern of symptoms follows this distribution — the little finger stays outside it, because it belongs to another nerve. The detail orients the diagnosis.

    The symptoms

    • Numbness and tingling in the thumb, index, middle, half of the ring finger.
    • Mostly nocturnal; they wake you from sleep. The reflex of shaking the hand until it passes is so constant that it has a name in clinical practice.
    • Dropping objects, reduced grip strength.
    • In advanced forms, the muscle at the base of the thumb wastes — a sign the nerve has been suffering for some time.

    Why it appears

    Rarely a single cause. Contributing factors include repetitive wrist activity, pregnancy and hormonal changes, hypothyroidism, diabetes, rheumatoid arthritis, an old fracture that narrowed the canal. In many patients it remains idiopathic — with no identifiable cause.

    How it is diagnosed

    It starts from the history and clinical examination. Two manoeuvres orient: the Phalen test (sustained wrist flexion reproduces the numbness) and Tinel's sign (tapping the nerve triggers tingling in the fingers). Confirmation and the degree of severity come from a nerve conduction study (EMG) — the same test also guides the choice of treatment.

    Conservative treatment

    In mild and moderate forms, treatment starts without surgery:

    • the night splint, which keeps the wrist in a neutral position and stops the nocturnal numbness — first line;
    • adjusting the activities that load the wrist;
    • a corticosteroid injection into the tunnel, with a temporary effect and diagnostic value.

    Many mild forms are controlled this way. When symptoms persist or weakness and wasting appear, conservative treatment is no longer enough and surgery is discussed — see when surgery is needed and carpal tunnel surgery.

    Frequently asked questions

    Which fingers go numb in carpal tunnel syndrome?

    The thumb, index, middle and half of the ring finger. Not the little finger — it belongs to another nerve, and its involvement points to a different cause.

    Does carpal tunnel go away on its own?

    Mild forms can improve with a splint and activity adjustment. Moderate and severe forms do not resolve on their own and need treatment.

    What is the Phalen test?

    You hold the wrist flexed for about a minute; if the numbness is reproduced, it points to carpal tunnel syndrome. It is a clinical sign, not a definitive diagnosis — that is confirmed with EMG.

    Is EMG needed?

    Usually yes: it confirms the diagnosis, measures the severity of the compression and guides the choice between conservative treatment and surgery.

    About the author

    Dr. Alexandru Florian Grecu, senior specialist in orthopedics and traumatology and Senior Lecturer at UMF Craiova. He treats carpal tunnel syndrome, conservatively and surgically. Details on the About page.

    Scientific references

    1. Phalen GS. The carpal-tunnel syndrome. Seventeen years' experience in diagnosis and treatment of 654 hands. J Bone Joint Surg Am. 1966;48(2):211–228.
    2. American Academy of Orthopaedic Surgeons (AAOS). Management of Carpal Tunnel Syndrome — Evidence-Based Clinical Practice Guideline. Adopted 2016, updated 2024.

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