If you have thumb arthritis at the base of your thumb, you may have noticed something strange. Your thumb joint can bend backward more than it used to. This is called hyperextension. It happens when the joint at the base of your thumb becomes damaged over time.
You might wonder if a surgeon needs to fix this backward bending when they operate on your thumb arthritis. This is an important question. A recent study looked at 32 people who had thumb surgery without fixing the backward bending joint. The results may surprise you.
Key Findings at a Glance
- Research shows that 77% of patients experienced pain reduction after thumb surgery
- According to this study, 25 out of 32 patients had only mild backward bending between 0 and 5 degrees
- Studies indicate that surgical correction of the backward bending joint is not needed when the angle is less than 15 degrees
- Patients reported excellent hand function and satisfaction without fixing the backward bending joint
- Grip strength and pinch strength were equal in both the operated and non-operated hands
In this article:
- What is thumb arthritis and why does it cause backward bending?
- What surgery did the researchers study?
- What did the researchers find?
- What does this mean for you?
- Common questions answered
- Conclusion
- Disclaimer
- Article source
What is thumb arthritis and why does it cause backward bending?
Thumb arthritis is also called rhizarthrosis. This is a big word that describes arthritis at the very base of your thumb. According to medical evidence, this type of arthritis makes up about 10% of all arthritis cases. It happens more often as people get older. It also happens more often in women than in men.
Here is where it gets interesting. When the joint at the base of your thumb gets damaged, the thumb bone can slide out of place. It moves up and to the side. This is called subluxation. When this happens, your thumb tries to balance itself. The next joint down your thumb starts to bend backward to make up for the problem at the base.
This next joint is called the metacarpophalangeal joint. We will call it the MCP joint for short. The MCP joint is the big knuckle where your thumb meets your hand. When this joint bends backward too much, we call it hyperextension.
What surgery did the researchers study?
The researchers looked at a surgery called the modified Burton Pellegrini trapeziectomy. Let us break this down into simple parts.
In this surgery, the doctor removes a small bone at the base of your thumb. This bone is called the trapezium. It is shaped like a trapezoid, which is why it has that name. When this bone is removed, the painful grinding between bones stops.
You may be wondering why this matters. When the trapezium bone is gone, there is a small space left behind. The surgeon fills this space with some of your own tissue. This acts like a cushion. It keeps your thumb bones from rubbing against each other.
The important part of this study is what the surgeons did NOT do. They did not fix the backward bending MCP joint. Usually, some surgeons think they need to fix this joint too. But these researchers wanted to see what happens if they leave it alone.
What did the researchers find?
Research shows that patients did very well after surgery, even without fixing the backward bending joint. The doctors measured success in several ways.
Pain relief
According to this study, patients had a 77% reduction in their pain scores. This means their pain went down by more than three quarters. Most people felt much better after the surgery.
Daily activities
The researchers used special questionnaires to ask patients about their daily life. These questionnaires are called DASH and PRWHE. They ask questions like: Can you open a jar? Can you button your shirt? Can you write?
The average DASH score was 19. The average PRWHE score was 21.8. Lower scores are better. These scores show that most patients could do their daily activities well.
Hand strength
Let us look closer at the strength tests. The researchers measured grip strength and pinch strength. Grip strength is how hard you can squeeze something in your whole hand. Pinch strength is how hard you can pinch something between your thumb and finger.
Studies indicate that both types of strength were equal in the operated hand and the non-operated hand. This means the surgery did not make the hand weaker.
How much backward bending did patients have?
This is the key part of the study. The researchers measured how much each MCP joint bent backward.
| Number of Patients | Degrees of Backward Bending |
|---|---|
| 25 | 0 to 5 degrees |
| 5 | 10 degrees |
| 2 | 15 degrees |
Most patients had only a little bit of backward bending. The researchers found that all these patients did well. They concluded that if the backward bending is less than 15 degrees, you do not need surgery to fix it.
Thumb movement
The doctors used something called the Kapandji test. This test checks if you can touch your thumb to different parts of your hand and fingers. It measures how well your thumb can move and reach.
According to medical evidence, 26 out of 32 patients had excellent scores on this test. This means their thumbs could move very well after surgery.
What does this mean for you?
If you have thumb arthritis and your doctor suggests surgery, you might be worried about the backward bending joint. This study brings good news.
Research shows that fixing the backward bending joint may not be necessary. If your MCP joint bends backward less than 15 degrees, you can probably skip that extra surgical step. Your results will likely be just as good.
This matters because simpler surgery often means:
- Shorter time in the operating room
- Less trauma to your tissues
- Faster healing
- Fewer complications
You may be wondering why some surgeons still fix the backward bending joint. Every patient is different. If your backward bending is more than 15 degrees, your surgeon might still recommend fixing it. Always talk to your doctor about your specific situation.
About this site
This website simplifies medical science about thumb pain and rhizarthrosis. We read published scientific articles from medical journals. Then we explain the findings in simple language that everyone can understand. We never make up facts. Everything comes from real research done by doctors and scientists. We invite you to explore more articles on this site to learn about your thumb health.
Common questions answered
Do I need surgery if my thumb bends backward?
According to this study, the backward bending itself is not the main problem. The arthritis at the base of your thumb is the main problem. If your backward bending is less than 15 degrees, research shows you do not need surgery to fix that part. Your surgeon will focus on treating the arthritis at the base of your thumb.
Will my hand be weak after thumb surgery?
Studies indicate that grip strength and pinch strength are equal in operated and non-operated hands after this surgery. This means your hand should not be weaker. The surgery removes the painful bone but preserves your strength.
How much will my pain improve?
Research shows that patients in this study had a 77% reduction in pain scores. Most people feel much better after surgery. However, every person is different. Talk to your doctor about what to expect.
How will I know if my backward bending is too much?
Your surgeon will measure the angle of your MCP joint. According to this study, angles less than 15 degrees do not need surgical correction. Your doctor will examine your hand and take measurements to help decide the best treatment for you.
Conclusion
Thumb arthritis can be painful and frustrating. When the joint at the base of your thumb wears down, it can cause other joints to bend in unusual ways. The backward bending of your thumb knuckle is one of these changes.
This study offers hope. Research shows that you may not need extra surgery to fix that backward bending joint. If the angle is less than 15 degrees, treating just the arthritis at the base of your thumb can give you excellent results.
Patients in this study reported less pain, good hand function, and satisfaction with their results. They did well without the extra surgical step.
If you are facing thumb surgery, talk to your surgeon about your specific situation. Ask about the angle of your backward bending joint. Discuss whether you really need that extra correction. This conversation can help you make the best choice for your health.
Disclaimer
This article is for information only. It is not medical advice. It does not replace the advice of your doctor. Every person and every medical situation is different. Always talk to your healthcare provider before making decisions about your treatment. Only your doctor can examine you and recommend the best treatment for your specific condition.
Article source
Pogliacomi, F., Oldani, D., Schiavi, P., Pedrazzini, A., Ferrari, A., Leigheb, M., Pedrini, M.F., Vaienti, E., Ceccarelli, F., & Calderazzi, F. (2022). Metacarpophalangeal joint hyperextension in rhizartrosis: is surgical correction necessary? Acta bio-medica : Atenei Parmensis.