Typing for many hours at a computer can cause tendinitis: MedlinePlus links it to overuse and repetitive movements, and the INSST lists it among the problems of continued keyboard use. As for carpal tunnel, MedlinePlus says that link has not been shown. The guidelines agree on positioning the keyboard and your wrists properly, taking breaks and seeing a doctor if it hurts.
What tendinitis is and why it is linked to typing
Tendinitis is the inflammation of a tendon, the fibrous tissue that joins a muscle to a bone. MedlinePlus, the health information service of the United States National Library of Medicine, attributes it to injury or overuse, and lists the thumb and the wrist among the places where it often appears.
It shows up as pain along the tendon, near a joint, which gets worse when you move it, and stiffness in the morning. To prevent it, MedlinePlus advises avoiding repetitive movements and overuse, and keeping your muscles strong and flexible.
The link with the keyboard is set out by the INSST (Instituto Nacional de Seguridad y Salud en el Trabajo, Spain's National Institute for Occupational Safety and Health) in its NTP 602 (one of its technical prevention notes), from 2001: continued keyboard use can cause tendinitis, tenosynovitis or carpal tunnel syndrome, and a well designed and well placed keyboard, breaks and a less intense pace of work seem to reduce them. The INSST itself asks for each technical note to be weighed according to its date, and this one is more than twenty years old.
De Quervain tendinitis
De Quervain tendinitis affects two tendons that run from the back of the thumb down the side of the wrist. MedlinePlus describes pain in that area when making a fist, gripping something or turning the wrist, and difficulty pinching with the thumb. As causes it names tennis, golf, rowing and frequently lifting babies and toddlers; writing, by hand or on a keyboard, is not on that list.
Carpal tunnel and the keyboard: what the sources say
Carpal tunnel syndrome is excessive pressure on the median nerve where it passes through the wrist. That nerve gives feeling and movement to the thumb side of the hand, which is why MedlinePlus describes numbness or tingling in the thumb and the next two or three fingers, pain in the hand or wrist, or pain that extends up to the elbow, clumsiness when gripping and weakness. According to the same source, it almost always appears between the ages of 30 and 60 and is more common in women.
On the keyboard, MedlinePlus is more cautious than the INSST note. It explains that repeating the same hand and wrist movement over and over can cause it, as can tools that vibrate, but that studies have not proved it is caused by typing on a computer or using a mouse. What it does accept is that those activities can inflame the tendons of the hand, narrow the tunnel and cause symptoms.
The two sources do not say the same thing. Where they do agree is on the practical side: the position of your wrist when typing, breaks and seeing a doctor as soon as symptoms appear.
When to see a doctor
If your hand or wrist hurts, or you notice tingling or loss of strength, make an appointment with your doctor. That is what the three MedlinePlus pages repeat: with symptoms of tendinitis, get it checked. For carpal tunnel it adds fingers that keep losing feeling, dropping things or the hand becoming clumsy. For De Quervain tendinitis, pain that does not improve or gets worse, a wrist that gets stiffer and stiffer, increasing numbness or fingers that turn white or purple.
This article is not a way to find out what you have or to treat it. The same pain can have different causes, and diagnosis and treatment are decided by a healthcare professional after examining you. While you wait for the appointment, for carpal tunnel MedlinePlus recommends taking frequent breaks when typing and stopping whenever you feel pain or tingling.
What Real Decreto 488/1997 and the INSST guide require
Real Decreto 488/1997 (the Spanish Royal Decree on work with display screens) sets the minimum conditions for a workstation with a screen; the INSST technical guide spells them out. On the keyboard, the annex to the Royal Decree requires it to be tiltable and separate from the screen, so it can be placed in a position that does not tire the arms or hands, and to leave space in front to rest them. The technical guide, updated in 2021, and NTP 602 put figures on that:
| Element | What they recommend | Source |
|---|---|---|
| Keyboard height | Flat: the middle row of keys no more than 30 mm above the base | INSST technical guide (2021) |
| Keyboard tilt | Between 0° and 15° from the horizontal | INSST technical guide (2021) |
| Hand support | At least 10 cm deep; if the keyboard does not have it, the same free space on the desk | INSST technical guide (2021) |
| Wrist rest | Level with the keyboard and 5 to 10 cm deep | INSST NTP 602 (2001) |
| Wrist | In a straight line with the forearm and hand, not bent up, down or to the sides | INSST NTP 602 (2001) |
| Mouse | As close as possible to the side of the keyboard, suited to your hand and with part of the hand or wrist resting on the desk | INSST NTP 602 (2001) |
| Breaks | Short ones, for example every 30 minutes, to get up and stretch | INSST technical guide (2021) |
Desk, chair and keyboard height
The annex to the Royal Decree requires a height-adjustable chair and a backrest adjustable in height and tilt; if even so your feet do not reach the floor comfortably, the technical guide recommends a footrest. NTP 602 advises a height-adjustable desk, and MedlinePlus sums it up from the hand's point of view: the keyboard low enough that your wrists do not bend upwards when typing.
If you work on a laptop
NTP 602 points out two problems with a laptop used every day: the keyboard is attached to the screen, so the two cannot both be placed at the right distance and height at the same time, and a smaller keyboard and mouse force you to strain your fingers. With an external keyboard and mouse, the keyboard is separate from the screen, as the annex to the Royal Decree describes. Of ergonomic keyboards, such as split ones, the 2021 guide says their usefulness depends on the task and on each person, and the NTP that there is not enough evidence to confirm their benefits.
Breaks
Real Decreto 488/1997 provides for alternating screen work with other tasks, or taking breaks when that is not enough, and allows collective agreements to set how often and how long they are. The technical guide, when it discusses sedentary work, gives as an example short breaks every 30 minutes to get up, walk and stretch your arms, neck and shoulders. In a law firm, alternating can mean saving phone calls or a paper file for between two briefs.
How to type less in a law firm
There are three ways to type less: reuse the texts that repeat, use shortcuts and dictate by voice. None of them is a treatment: they only remove keystrokes. To get an idea of how many, we measured it on the text of Real Decreto 488/1997 itself: about 2,200 words and almost 14,000 characters counting spaces and punctuation, 6.3 per word. At that rate, a 2,000-word brief means at least about 12,600 keystrokes, not counting capital letters, accents or what is deleted and typed again.
The texts that repeat
Headings, closing formulas, the details of the procurador (the party's court representative in Spain), the data protection clause in your emails: in a law firm the same sentences are rewritten every day. Word stores them with AutoText: you select the text, press Alt+F3 and give it a name; then you insert it from Insert, Quick Parts, AutoText (it is not in the web version of Word). For short snippets, AutoCorrect replaces a few letters with a text of up to 255 characters as you type.
Keyboard shortcuts
Each shortcut saves a trip to the mouse and several clicks. The ones for what you do most during the day (copy, paste, undo, save, find) are enough, plus checking which shortcut the commands you currently look for in the menus have. The ones that pay off most in a long document, checked in the Spanish version of Word, are in Word keyboard shortcuts for briefs and contracts.
Dictating by voice
Dictating is what removes the most keystrokes: the draft comes out as you speak and the keyboard is left for reviewing. It is also faster, as we show with numbers in how much time you save by dictating instead of typing. You don't need to pay to try it: Windows has voice typing with Win+H in Windows 11 and the Mac has its own system dictation. What changes the result most is the microphone: one close to your mouth understands you even if you speak quietly, as we explain in which microphone to choose for voice dictation.
With ablalo you dictate in any program with a keyboard shortcut: you speak and the text appears, already punctuated, where the cursor is, in Word, in your email or in your case management software. If you share an office, whisper mode is designed for dictating very quietly without losing words.
What neither the workstation nor dictation solves
Neither a well adjusted workstation nor dictation guarantees that a hand injury will not appear. The INSST technical guide says so about the Royal Decree itself: complying with it does not by itself ensure there are no health risks. It also points out that musculoskeletal disorders have several causes at once, stress among them. MedlinePlus adds causes unrelated to the workstation: age, rheumatoid arthritis or diabetes for tendinitis, and pregnancy, obesity or wrist fractures for carpal tunnel, among others.
Dictation has its limits too: it removes the keystrokes of the draft, but reviewing and formatting are still done with the keyboard and mouse, and you cannot always speak out loud.
In short
Typing for many hours can cause tendinitis, according to the INSST; for carpal tunnel, MedlinePlus does not consider it proven. The official guidelines agree on the practical side: a flat keyboard separate from the screen, straight wrists, the mouse next to the keyboard, short and frequent breaks and, at any pain or tingling, a doctor. Reusing texts, using shortcuts and dictating do not cure or prevent anything, but they remove thousands of keystrokes from every long document.
Sources: MedlinePlus (United States National Library of Medicine), Tendinitis (reviewed July 2024), De Quervain tendinitis (June 2026) and Carpal tunnel syndrome (June 2025); BOE, Royal Decree 488/1997 of 14 April on display screen equipment (in Spanish); INSST, Technical guide on display screen equipment (2021, in Spanish) and NTP 602, the ergonomic design of workstations with display screens (2001, in Spanish); Microsoft, Create reusable text snippets. Checked on 22 October 2026.
Frequently asked questions
Can you get tendinitis from typing a lot?
You can. MedlinePlus links tendinitis to overuse and repetitive movements, and the INSST's NTP 602 includes it among the disorders that continued keyboard use can cause. If your hand or wrist already hurts, make an appointment with your doctor.
Can you get tendinitis from writing by hand?
The official sources consulted do not mention handwriting specifically: MedlinePlus links tendinitis to overuse and repetitive movements in general. If writing by hand causes you pain, see your doctor about it.
Can De Quervain tendinitis come from writing?
MedlinePlus does not mention writing among its causes: it cites tennis, golf, rowing and frequently lifting babies and toddlers. If the area around your thumb and wrist hurts, the person who can tell you where it comes from is your doctor.
Is carpal tunnel caused by using a keyboard?
According to MedlinePlus, this has not been shown: it explains that studies have not proved it is caused by typing on a computer or using a mouse, although those activities can inflame the tendons of the hand, narrow the tunnel and cause symptoms. A 2001 INSST technical note did include it among the problems of continued keyboard use.
Which keyboard is best for carpal tunnel?
The official guidelines do not point to any model: the INSST's NTP 602 says it cannot be generalised that one design is better in every case. The INSST technical guide asks for a flat keyboard (middle row no more than 30 mm above the base), tilted between 0° and 15°, separate from the screen and with space in front to rest your hands.
How can you avoid carpal tunnel when using a keyboard?
MedlinePlus recommends improving the position of your wrist when typing, with aids such as split keyboards, keyboard trays or wrist rests, taking frequent breaks and stopping whenever you feel pain or tingling. No measure guarantees it, because causes unrelated to the workstation also play a part, such as pregnancy, arthritis or wrist fractures.