New here? Read this first. Rhizarthrosis is arthritis at the base of your thumb. It is very common, it is not dangerous, and finding out you have it does not mean you need surgery. This page walks you through it, one step at a time, in plain words.
Step 1: Understand what is wrong
The joint at the base of your thumb lets you pinch and grip. Over time the smooth surface inside it can wear away. When that happens, the bones rub and it hurts to open jars, turn keys, or hold a pen. That wearing-out is what doctors call rhizarthrosis (also called thumb CMC arthritis or basal thumb arthritis).
How the thumb works
Why this one joint wears out before the others.
Read the guide
How it is diagnosed
The simple hand tests and X-rays a doctor uses.
Read the guide
Who gets it and why
Age, family history, and other things that raise the risk.
Read the guide
Step 2: Try the things that are not surgery
Most people start here, and for many it is enough. A brace rests the sore joint, hand exercises make the muscles around it stronger, and injections can calm the pain for a while. Give each one a fair chance before you think about an operation.
Treatments without surgery
Braces, exercises, and injections, and how well each one works.
Read the guide
Thumb braces
Which brace fits your hand, and when to wear it.
Read the guide
Step 3: Compare your options
If the pain is still stopping you from doing what you want, it helps to see every choice side by side, from the simplest to surgery, before you decide anything.
All treatments compared
Every option, side by side, with real results.
Compare
Surgery options
The main operations, in plain words, good and bad points.
Read the guide
Thumb implants
The artificial joints, with how long they really last.
Browse the directory
Step 4: Know what recovery looks like
Whichever path you choose, getting your hand working again takes time and a bit of practice. Knowing what to expect makes it far less worrying.
Getting better after treatment
What recovery looks like and how long it takes.
Read the guide
Clinical trials
New treatments being studied, and how to take part.
See trials
Step 5: Look things up any time
Come back whenever you need to. If a word confuses you, the glossary explains it simply, and the blog adds new plain-language summaries of research as it comes out.
Word list
Hard medical words made simple.
Open the glossary
Latest research, explained
New studies in plain language.
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This page is educational and built from published, peer-reviewed research. It is not medical advice. Every person is different, so talk to a hand surgeon or hand therapist about your own situation.