Osteoarthritis Of The Thumb

Osteoarthritis of the thumb – 1st CMC Joint

Osteoarthritis of the thumb (1st CMC Joint) is a common condition that affects the first carpometacarpal (CMC) joint, located at the base of the thumb where the first metacarpal bone (the bone in your thumb) meets the trapezium bone (a carpal bone in your wrist). This joint allows the thumb to move in various directions, contributing to hand function, including gripping, pinching, and grasping. When osteoarthritis affects this joint, it leads to pain, stiffness, and decreased range of motion, making activities that require fine hand movements, like writing or opening jars, difficult.

Symptoms of 1st CMC Joint Osteoarthritis:

Pain at the base of the thumb, especially with activities that involve gripping or pinching.
Swelling around the joint, which can worsen with activity.
Stiffness in the thumb, making it difficult to move, especially in the morning.
Decreased Range of Motion: The thumb may become less mobile and difficult to move through its full range.
Weakness: The thumb may lose strength, affecting the ability to perform tasks like gripping objects or opening bottles.
Tenderness over the 1st CMC joint, particularly when pressure is applied.
Visible Deformity: In advanced cases, the thumb may become misaligned or develop visible lumps or bony growths (bone spurs) near the joint.

Our Treatment Options

Ultrasound Guided Cortisone Injections

An ultrasound-guided cortisone injection for thumb osteoarthritis helps to reduce inflammation within the CMC joint, alleviating pain and improving mobility. Using ultrasound guidance, the clinician ensures precise delivery of the medication into the affected joint, enhancing its effectiveness.

Ultrasound Guided Hyaluronic Acid Injections

Hyaluronic acid injections for thumb arthritis help to restore lubrication within the joint, potentially easing stiffness and improving joint function. Like cortisone, these are performed under ultrasound guidance for accuracy.

Ultrasound Guided PRP Injections

An ultrasound-guided PRP injection for thumb osteoarthritis delivers concentrated growth factors from your own blood into the CMC joint to help reduce inflammation, ease pain, and support joint healing. Ultrasound guidance ensures precise placement for optimal effectiveness.

Your Care Pathway with us

To book an appointment you can call our normal reception line, 0142084487, email direct to info@altonpainclinic.co.uk or click the button given below.
Comprehensive Musculoskeletal examination and testing.
Same day Ultrasound Guided Injection for pain relief.
Discussion of your treatment plan; Treatment Plans can include i.e advanced treatments for ex. Cortisone Injections, Hyaluronic injections and various other options tailored for your specific needs.

Pain Reduction with Ultrasound-Guided Cortisone Injections

Mechanism of Action: Cortisone is a powerful anti-inflammatory medication that reduces inflammation within the wrist joint. When injected under ultrasound guidance, cortisone helps to decrease the inflammation that contributes to pain and stiffness in wrist osteoarthritis.
Reduction in Inflammation: Inflammation is a primary cause of pain in wrist osteoarthritis. Cortisone injections target this inflammation directly, leading to a reduction in pain and an improvement in joint mobility.
Improved Joint Function By decreasing inflammation and pain, cortisone injections can help improve the function of the wrist joint. This can result in enhanced mobility and a greater ability to perform everyday tasks without discomfort.
Enhanced Quality of Life: Effective management of wrist osteoarthritis symptoms with cortisone injections can lead to a significant improvement in your quality of life. Patients often experience less pain, better joint function, and increased ease in performing daily activities.

Pain Reduction with Ultrasound-Guided Hyaluronic Acid Injections

Lubricates the Joint: By replenishing hyaluronic acid in the thumb joint, the injection helps to restore lubrication, reducing the friction between bones that causes pain during movement.
Enhances Shock Absorption: The injection improves the cushioning within the joint, which helps to reduce the impact and pressure on the damaged cartilage, easing discomfort and stiffness.
Reduces Inflammation: Hyaluronic acid has anti-inflammatory properties that help to decrease swelling and stiffness in the thumb, providing relief from the pain associated with osteoarthritis.
Delays the Need for Surgery: As a non-invasive option, hyaluronic acid injections offer a way to manage thumb osteoarthritis pain without resorting to surgical interventions.

Pain Reduction with Ultrasound-Guided PRP Injections

Delivers growth factors directly to the joint: PRP is injected into the affected area to target the source of pain in thumb osteoarthritis
Reduces inflammation: Helps modulate the inflammatory process within the CMC joint, decreasing pain and swelling
Supports tissue repair: Promotes the body’s natural healing response to improve joint environment
Improves joint function: Enhances mobility and reduces stiffness over time
Ultrasound guidance ensures accuracy: Precise placement of PRP into the joint maximises effectiveness and outcomes
Gradual, longer-term relief: Works over time to reduce pain rather than providing only immediate, short-term relief

Anatomy

The anatomy of the thumb’s 1st carpometacarpal (CMC) joint is essential to understand when addressing osteoarthritis (OA) in this joint. The 1st CMC joint is located at the base of the thumb and allows for the wide range of motion and dexterity that the thumb provides. This joint is critical for grasping, pinching, and holding objects. Here’s a breakdown of its anatomical structure:

1. Bones Involved:

First Metacarpal Bone: The first metacarpal is the bone in the palm of your hand that connects to the thumb. It is the largest of the metacarpals and extends into the thumb.
Trapezium Bone: The trapezium is one of the eight carpal bones in the wrist, located in the row closest to the thumb. It articulates with the first metacarpal to form the 1st CMC joint.

These two bones (the first metacarpal and the trapezium) meet at the 1st CMC joint, where the thumb’s primary movements, including opposition, abduction, and flexion, occur.

2. Joint Type:

The 1st CMC joint is a saddle joint. This means the joint has two concave and convex surfaces that allow the thumb to move in multiple directions (i.e., up/down, side-to-side, and rotational movement). This mobility is essential for performing actions like pinching and grasping.

3. Ligaments:

Ligaments help stabilize the 1st CMC joint and prevent excessive movement:

Anterior Oblique Ligament (AOL): This ligament provides stability to the thumb during grasping and opposition, especially during forceful gripping.
Posterior Oblique Ligament: Works with the anterior oblique ligament to stabilize the joint.
Radial Collateral Ligament: Helps stabilize the joint from side-to-side motion.
Ulnar Collateral Ligament: Stabilizes the joint and limits excessive movement in the opposite direction.

4. Tendons:

The tendons in the thumb that pass through this joint play a key role in moving the thumb:

Flexor Pollicis Longus (FPL): The tendon of the flexor pollicis longus muscle helps flex the tip of the thumb.
Extensor Pollicis Brevis (EPB) and Extensor Pollicis Longus (EPL): These tendons help extend the thumb, enabling it to straighten out.
Abductor Pollicis Longus (APL): This tendon helps move the thumb away from the hand (abduction).
Opponens Pollicis: This muscle allows for the thumb’s opposition, where the thumb touches the fingertips, which is a critical action for gripping.

5. Cartilage:

The joint surfaces of the 1st CMC joint are covered with articular cartilage that allows for smooth motion. In osteoarthritis, this cartilage wears away, causing bones to rub against each other, which leads to pain, inflammation, and limited movement.
Subchondral Bone: Below the cartilage, the bone can become exposed as the cartilage thins, leading to further irritation and bone changes (such as the formation of bone spurs).

6. Joint Capsule:

The joint capsule surrounds the 1st CMC joint, holding the bones together and providing stability. In the case of arthritis, the joint capsule can thicken and become inflamed, contributing to the stiffness and pain associated with OA.

7. Synovial Fluid:

The 1st CMC joint is lined with a synovial membrane, which secretes synovial fluid to lubricate the joint and reduce friction. In osteoarthritis, the inflammation of the synovial lining can result in swelling and discomfort.

8. Muscles Surrounding the Joint:

Thenar Muscles: These muscles are located at the base of the thumb and contribute to its movement. These include the flexor pollicis brevis, abductor pollicis brevis, and opponens pollicis muscles. In advanced OA, muscle weakness may develop due to joint dysfunction.

Function of the 1st CMC Joint:

The 1st CMC joint is essential for the thumb’s ability to perform complex motions that allow for:

Opposition: The thumb can touch the tips of the other fingers, which is vital for grasping objects.
Flexion and Extension: The thumb can bend toward and away from the palm.
Abduction and Adduction: The thumb can move away from and toward the hand, allowing for better control when pinching or gripping.

Osteoarthritis in the 1st CMC Joint:

Cartilage breakdown: In osteoarthritis, the articular cartilage in the 1st CMC joint breaks down, leading to pain, swelling, and deformity.
Bone changes: The bones may form osteophytes (bone spurs) as the joint deteriorates.
Ligament strain: The ligaments surrounding the joint may become stretched or damaged, further decreasing the stability of the joint.

What Is the CMC Joint?

The carpometacarpal joint — commonly shortened to CMC joint or CMCJ joint — is the first carpometacarpal joint (1st carpometacarpal joint), sitting at the base of the thumb where it meets the wrist. This is technically known as the first carpometacarpal articulation, and it’s this joint’s saddle-shaped structure that gives the thumb its wide range of movement, allowing it to pinch, grip and oppose the fingers.

Because the thumb joint CMC bears significant load during everyday gripping and pinching tasks, it’s one of the most common sites for osteoarthritis in the hand. This is sometimes referred to more broadly as the CMC joints or CMC joints of the thumbs when both hands are affected, or simply thumb CMC arthritis.

What Is Thumb Arthritis (CMC Joint OA)?

Thumb arthritis, or arthritis of the CMC joint, develops when the cartilage cushioning the carpometacarpal joint of the thumb gradually wears down. This causes the bones to rub together, leading to pain, stiffness, swelling, and sometimes a visible bony prominence at the base of the thumb. Thumb OA is more common with age and tends to affect women more frequently than men, and can be aggravated by repetitive gripping or pinching activities.

Diagnosis

During your evaluation for 1st CMC Joint Osteoarthritis (OA), your clinician will gather information about your overall health, medical history, and specific symptoms. They will conduct a detailed examination of your hand and thumb to assess the condition of the 1st carpometacarpal (CMC) joint. This examination will include various physical tests and assessments to help diagnose the presence of osteoarthritis and determine the best treatment approach. The evaluation may involve:

1. Palpation:

Your clinician will carefully feel (palpate) the base of your thumb, specifically the 1st CMC joint, to check for tenderness, swelling, or warmth. This is important for identifying inflammation in the joint that might indicate OA.

2. Range of Motion Test:

The clinician will ask you to move your thumb in different directions, such as flexion, extension, abduction, and opposition (touching the thumb to the other fingers). Limited movement or pain during these motions can be a sign of osteoarthritis in the 1st CMC joint.

3. Grind Test:

This test is commonly used to diagnose 1st CMC OA. The clinician will gently apply pressure to the 1st metacarpal bone while rotating or compressing it to simulate the movements of the joint. Pain during this test can be indicative of joint degeneration and OA.

4. Strength Testing:

The clinician will assess the strength of your thumb, especially its ability to grip or pinch. In osteoarthritis, muscle weakness can occur due to joint dysfunction. They may ask you to perform activities like gripping a ball or pinching to gauge the strength of the thumb muscles.

5. Deformity Observation:

In more advanced cases of OA, visible deformities or changes in the shape of the thumb joint, such as joint enlargement or bony spurs (osteophytes), may be present. The clinician will look for any misalignment or abnormal positioning of the thumb.

6. Ultrasound:

In some cases, ultrasound may be used to visualize soft tissue, joint swelling, and inflammation around the 1st CMC joint. The clinician may use ultrasound to assess the extent of damage to the cartilage, detect fluid accumulation, and rule out other potential conditions.

8. Assessing Functional Limitations:

The clinician may ask you about specific activities you have difficulty performing due to pain or stiffness, such as opening jars, typing, or gripping objects. These functional limitations help the clinician understand the severity of your condition and how much it impacts your daily life.

9. Observation of Muscle Atrophy:

In advanced stages of 1st CMC OA, muscle wasting (atrophy) may occur due to disuse or the joint’s instability. The clinician will check for signs of atrophy in the thenar muscles at the base of the thumb, which may be weakened as a result of the joint dysfunction.

10. Assessment of Pain:

The clinician will ask you to rate your pain on a scale and determine whether it’s constant or intermittent. They will also inquire about any pain relief strategies you’ve used, such as rest, heat, or pain medications, and how effective they have been.

Frequently Asked Question

What is the CMC joint?

The CMC (carpometacarpal) joint is the joint at the base of the thumb, where it meets the wrist. It’s one of the most common sites of hand osteoarthritis due to the load it bears during gripping and pinching.

How do you test for thumb arthritis?

A clinician will perform a thumb arthritis test — gently compressing and rotating the base of the thumb — to check for pain, grinding, or crepitus, which indicate CMC joint osteoarthritis.

What does CMC joint arthritis feel like?

Common symptoms include pain, stiffness and reduced grip strength at the base of the thumb, particularly during pinching or gripping activities, sometimes with a visible bony prominence.

How effective is a cortisone injection for CMC joint arthritis?

Many patients experience meaningful pain relief for weeks to months following an ultrasound-guided cortisone injection, though the effect can vary depending on the severity of joint changes.

Is thumb arthritis common?

Yes, the CMC joint is one of the most frequently affected joints by osteoarthritis in the hand, particularly in women over 40.

Osteoarthritis Of The Thumb