Arthritis vs. Tendonitis: What’s Causing Your Joint Pain?

Joint pain is one of the most common reasons people seek medical care, but not all joint pain comes from the same source. Two conditions that are often confused are arthritis and tendonitis. While both can cause discomfort, stiffness, and difficulty with movement, they affect different structures in the body and require different approaches to diagnosis and treatment.

Understanding whether your pain is coming from a worn joint surface or an irritated tendon can help you take the right steps toward recovery. At Essential Sports & Spine, Dr. Verma helps patients identify the true source of their pain through a comprehensive evaluation that looks beyond symptoms alone.

What Is the Difference Between Arthritis and Tendonitis?

Arthritis and tendonitis both involve pain and inflammation around joints, but they affect different tissues.

Arthritis is a condition that affects the joint itself. In the most common form, osteoarthritis, the protective cartilage that cushions the ends of bones gradually breaks down. As the cartilage wears away, bones can begin to rub against each other, leading to pain, stiffness, swelling, and reduced mobility.

Tendonitis, on the other hand, affects the tendons, which are thick bands of connective tissue that attach muscles to bones. When a tendon becomes irritated, inflamed, or damaged due to overuse or repetitive stress, it can cause localized pain and weakness near a joint.

Although arthritis and tendonitis can occur in the same area, such as the shoulder, knee, hip, or elbow, the underlying cause of pain is different.

What Does Arthritis Pain Feel Like?

Arthritis pain is typically related to changes inside the joint. Many patients describe arthritis symptoms as a deep ache, stiffness, or discomfort that worsens with activity.

Common signs of arthritis include:

• Joint stiffness, especially after waking up or sitting for long periods
• Pain that increases with weight-bearing activities
• Swelling around the joint
• A grinding, clicking, or popping sensation
• Reduced range of motion
• Pain that may worsen over time

Many people with arthritis notice that their symptoms are predictable. For example, knee arthritis may become more noticeable when climbing stairs, walking longer distances, or standing for extended periods.

What Does Tendonitis Pain Feel Like?

Tendonitis pain is usually more focused around a specific tendon rather than deep within the joint. It often develops from repetitive movements, sports activities, occupational demands, or sudden increases in activity.

Common signs of tendonitis include:

• Pain directly over a tendon
• Tenderness when touching the affected area
• Pain with specific movements or resistance
• Weakness during certain activities
• Stiffness or discomfort after exercise
• Gradual worsening with repeated use

Examples include tennis elbow, rotator cuff tendon irritation, Achilles tendon problems, and patellar tendon pain.

Unlike arthritis, tendonitis symptoms are often more closely tied to specific movements or activities.

Can Arthritis and Tendonitis Happen at the Same Time?

Yes. Arthritis and tendonitis can occur together, which can make identifying the primary source of pain more challenging.

For example, a patient with shoulder arthritis may also develop rotator cuff tendon irritation because changes in joint mechanics alter how the shoulder moves. Similarly, knee arthritis may contribute to increased stress on surrounding tendons and soft tissues.

This is why an accurate diagnosis is important. Treating only one source of pain may not provide complete relief if another condition is contributing to symptoms.

How Do Doctors Diagnose Arthritis vs. Tendonitis?

Determining whether pain is caused by arthritis, tendonitis, or another condition requires more than simply identifying where the pain occurs.

A thorough evaluation may include:

• Reviewing symptoms and activity patterns
• Performing a physical examination
• Assessing joint stability and range of motion
• Evaluating muscle strength
• Using diagnostic imaging when appropriate

X-rays can help identify changes associated with arthritis, such as joint space narrowing or bone changes. Ultrasound or MRI imaging may be useful when evaluating tendon injuries or soft tissue problems.

At Essential Sports & Spine, Dr. Verma focuses on identifying the specific pain generator rather than assuming all joint pain comes from the same condition.

Are Arthritis and Tendonitis Treated the Same Way?

No. Treatment depends on the structure causing the pain and the severity of the condition.

Arthritis treatment may focus on improving joint function, reducing inflammation, and slowing progression through approaches such as:

• Physical therapy and targeted exercise
• Activity modification
• Strengthening surrounding muscles
• Regenerative medicine options when appropriate
• Injection-based treatments designed for specific conditions

Tendonitis treatment often focuses on improving tendon health and restoring proper movement patterns. This may include:

• Physical therapy
• Mobility and strengthening programs
• Load management strategies
• Correcting movement mechanics
• Image-guided procedures when appropriate

The goal is not simply to reduce pain temporarily, but to address why the tissue is struggling in the first place.

When Should You See a Specialist for Joint Pain?

Persistent joint pain should not be ignored, especially when it begins affecting daily activities, exercise, work, or sleep.

You may benefit from an evaluation if you experience:

• Pain lasting more than a few weeks
• Increasing difficulty with movement
• Swelling or instability
• Loss of strength
• Symptoms that return repeatedly after activity
• Limited improvement with rest

Early evaluation can help prevent a minor issue from becoming a more significant problem.

How Can You Tell If Your Joint Pain Is Coming From Arthritis or Tendonitis?

The difference between arthritis vs. tendonitis often comes down to understanding what structure is causing the pain. Arthritis typically involves changes within the joint, while tendonitis involves irritation or injury of the connective tissues surrounding the joint.

Because symptoms can overlap, an accurate diagnosis is the first step toward effective treatment. At Essential Sports & Spine, Dr. Verma evaluates each patient individually to determine the underlying cause of pain and develop a personalized plan focused on restoring function and helping patients return to the activities they enjoy.

If you want to go deeper on this, the specific protocols I use, how I think about system selection, and what I tell every patient after an injection, I cover all of that in my paid newsletter, Essentials of Healing. You can find it at nikhilvermamd.substack.com.