Lyme Disease Arthritis

Introduction

Lyme disease is an infection caused by bacteria spread through the bite of an infected black-legged tick, often called a deer tick. Early symptoms of Lyme disease may include fever, fatigue, headache, and a characteristic “bull’s-eye” skin rash. If untreated, the bacteria can spread through the body and cause more serious problems. One possible complication is Lyme disease arthritis, which affects the joints and leads to musculoskeletal symptoms such as pain, swelling, and stiffness.

What is Lyme Disease Arthritis?

Lyme disease arthritis occurs when the bacteria from Lyme disease spread into a joint and trigger inflammation. The immune system’s response to the infection causes swelling, pain, and damage to the joint lining. The most commonly affected joint is the knee, although other large joints such as the hip, shoulder, or ankle can also be involved. Symptoms may come and go, and the swelling is often more dramatic than the amount of pain, which can help distinguish it from other types of arthritis.

Diagnosing Lyme Disease Arthritis

To diagnose Lyme disease arthritis, a doctor will ask about the patient’s medical history, recent outdoor activity, and whether they may have been exposed to ticks. They will examine the affected joints for swelling, warmth, and limited motion. Blood tests are often used to confirm the diagnosis by detecting antibodies to the Lyme bacteria. Imaging tests such as X-rays or MRI may be ordered to look for joint damage or rule out other causes of symptoms, although these tests are not always needed.

Treatment of Lyme Disease Arthritis

The main treatment for Lyme disease arthritis is antibiotics, usually taken for several weeks. These medications help eliminate the bacteria causing the joint inflammation. Nonsteroidal anti-inflammatory drugs (NSAIDs) may also be recommended to reduce pain and swelling. In some cases, a doctor may remove fluid from the joint with a needle to relieve pressure and improve comfort. Physical therapy is sometimes suggested to restore strength and flexibility after the infection has been treated.

Is Surgery Ever Needed?

Surgery is rarely required for Lyme disease arthritis. However, if joint inflammation continues even after appropriate antibiotic treatment, a doctor may recommend a procedure called arthroscopic synovectomy, which removes inflamed tissue from inside the joint. This is considered only in severe or persistent cases and is not a common part of treatment.

Prognosis and Long-Term Outlook

The outlook for patients with Lyme disease arthritis is generally good, especially when treated early with antibiotics. Most people experience significant improvement or complete resolution of symptoms. However, in some cases, joint inflammation may persist, leading to chronic arthritis-like symptoms. Rarely, untreated or severe cases can result in long-term joint damage. With proper treatment and follow-up, most patients recover well and are able to return to their normal activities.

Edited by Stephen Pinney MD, September 13th 2025.