Could a Bone Spur Near Your Thumb Be Causing Your Arthritis?

If you have thumb pain or thumb arthritis, you may be wondering what is actually happening inside your hand. Sometimes the answer lies in a surprising place. A small bone next to your thumb may hold a clue.

Researchers found that a tiny bone spur near the base of your thumb can actually cause thumb arthritis. This bone spur grows on the second bone in your hand. It connects to your thumb through a special band of tissue. When that band gets stretched too much, it can turn into bone. Then your thumb begins to move out of place.

Here are three key points from this study:

• A bone spur on the second hand bone is linked to thumb arthritis.
• A band of tissue connects your thumb to this second bone.
• When that band turns to bone, your thumb can slide out of position.

What Is Rhizarthrosis?

Let us start with what rhizarthrosis means. This is just a fancy word for arthritis at the base of your thumb. The word comes from old Greek words. Rhiza means root. Arthrosis means joint wear and tear. So rhizarthrosis means arthritis at the root of the thumb.

Many people with thumb pain have this condition. It can make it hard to open jars, turn keys, or hold a pen. The base of your thumb feels sore and weak.

What Did the Study Find?

According to this study, researchers proved something important. They found a clear connection between a bone spur and thumb arthritis. Let me explain what that means.

Here is where it gets interesting.

Your hand has five long bones that connect your wrist to your fingers. These are called metacarpal bones. Think of them as the bones in the main part of your hand. The first one connects to your thumb. The second one connects to your pointer finger.

Research shows that a bone spur can grow at the base of the second metacarpal bone. That is the bone that connects to your pointer finger. This spur is not just a random growth. It actually causes problems for your thumb.

How Does This Happen in Your Hand?

You may be wondering how a bone spur near your pointer finger affects your thumb. The answer lies in a special band of tissue.

Your thumb bone is connected to the base of the second hand bone by a ligament. A ligament is like a strong rubber band. It holds bones together and helps them stay in the right position.

According to this study, when you use your thumb over and over, the ligament experiences high pulling forces. These are called tensile stresses. Think of it like pulling on a rope again and again.

Over time, these strong pulling forces stretch the ligament. The ligament begins to change. Parts of it start to turn into bone. This process is called ossification. When soft tissue turns into hard bone, it loses its ability to stretch and flex.

What Happens When the Ligament Turns to Bone?

Let us look closer at what happens next.

A healthy ligament can stretch a little and spring back. It keeps your thumb in the right place. But when the ligament becomes bone, it cannot do its job anymore. Studies indicate that the ligament loses its essential function.

The bony ligament is stiff. It cannot hold your thumb in position the way it used to. Your thumb starts to slide out of place.

Why Does the Thumb Move Out of Place?

Research shows that when the ligament can no longer hold things together, the thumb moves outward. Doctors call this radial subluxation. Let me break down those words.

Radial means toward the radius bone. The radius is one of the two bones in your forearm. It is on the thumb side. So radial subluxation means your thumb slides toward the outside of your hand.

When your thumb moves out of its proper position, the joint surfaces do not line up correctly anymore. They rub against each other in the wrong way. This causes wear and tear. Over time, this leads to arthritis.

The Chain of Events

Here is the whole story in simple steps:

• You use your thumb over and over for daily activities.
• The ligament connecting your thumb to the second hand bone experiences strong pulling forces.
• These forces stretch the ligament and cause parts of it to turn into bone.
• The bony ligament becomes stiff and loses its ability to hold your thumb in place.
• Your thumb slides outward and sits in the wrong position.
• The misaligned joint wears down and develops arthritis.

This research explains why some people develop thumb arthritis. It is not just random wear and tear. There is a specific mechanical reason. The bone spur at the second metacarpal bone plays a key role in this process.

Frequently Asked Questions

What causes a bone spur to form at the second metacarpal bone?

According to this study, bone spurs form in response to repeated pulling forces on the ligament that connects the thumb bone to the second hand bone. When the ligament is stretched over and over, parts of it can turn into bone. This creates a bone spur.

Can a ligament really turn into bone?

Yes. This process is called ossification. When soft tissues like ligaments experience repeated stress or pulling, the body sometimes responds by laying down bone tissue. The flexible ligament becomes hard and stiff like bone.

Does everyone with thumb arthritis have this bone spur?

This study shows that there is a causal connection between the bone spur and thumb arthritis. However, the research does not tell us how common this is. Not every case of thumb arthritis may have the same cause. Your doctor can examine your hand and take X rays to see what is happening in your specific case.

What does radial subluxation of the thumb feel like?

When your thumb slides out of position, you may notice that the base of your thumb looks different or bulges outward. You might feel pain, weakness, or instability. Gripping and pinching may become difficult and uncomfortable.

What This Means for You

This research helps us understand one pathway that can lead to thumb arthritis. According to this study, a bone spur at the base of the second hand bone can set off a chain of events. The ligament connecting your thumb changes. It loses its flexibility. Your thumb moves out of place. Arthritis develops.

If you have thumb pain, it is worth talking to a doctor. They can examine your hand and take images to see if you have this bone spur. Understanding the cause of your arthritis can help guide your treatment.

Remember that knowledge is power. The more you understand about what is happening in your hand, the better you can work with your healthcare team to find relief.

Disclaimer

This article is for informational purposes only. It is not medical advice. Always consult with a qualified healthcare professional about your specific condition. Only a doctor can diagnose your thumb pain and recommend appropriate treatment.

Study Citation

This article is based on research by Koebke, J., Thomas, W., and Winter, H. J., published in 1983 in Z Orthop Ihre Grenzgeb.

Read the original study here: https://doi.org/10.1055/s-2008-1051324