Synovial Osteochondromatosis: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Synovial Osteochondromatosis?
A primary care doctor is often the first stop and can order X-rays and other tests. If the exam and images point to synovial osteochondromatosis, the doctor will usually refer the patient to an orthopedic surgeon, who confirms the diagnosis and performs surgery if needed.
What it is
Synovial osteochondromatosis is a rare condition in which the synovium, the soft lining of a joint, grows small lumps of cartilage. Over time, some of these lumps can break loose and float inside the joint space. The condition most often affects one large joint, most commonly the knee; the hip, elbow, shoulder, and ankle can also be affected.
Symptoms
The most common signs are pain and swelling in one joint. The joint may feel stiff and hard to move. Many people notice a clicking, popping, or grinding feeling when the joint moves. If loose pieces get caught, the joint can lock in place for a moment.
Causes and who gets it
Doctors do not know the exact cause. It may be linked to long-term joint irritation or injury, but it can also appear without any clear reason. It most often affects men between the ages of 20 and 50, though anyone can get it.
How doctors diagnose it
Doctors start with a physical exam and questions about symptoms. X-rays can show the lumps of cartilage, many of which contain calcium. An MRI or CT scan may be used to see pieces that do not show up on X-ray.
Treatment
Treatment depends on how bad the symptoms are. Mild cases may be managed with rest, anti-inflammatory medicines, and physical therapy. When pain or locking is troublesome, surgery is the main treatment. Surgeons remove the loose pieces and often the abnormal joint lining, sometimes using a small camera called an arthroscope.
When to see a doctor
See a doctor if a joint has lasting pain, swelling, stiffness, or a clicking or locking feeling. Seek care sooner if the joint suddenly locks or the pain gets much worse.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance for visits; a concierge doctor usually charges more and often works alongside insurance. These doctors can examine the joint, order imaging, suggest pain relief, and follow progress over time, referring the patient to an orthopedic surgeon when surgery looks likely.
Common questions
Is synovial osteochondromatosis cancer?
No. The lumps are benign, which means they are not cancer and do not spread to other parts of the body. Doctors still check them carefully to be sure of the diagnosis.
Will it come back after surgery?
It can, but it does not always. Removing the abnormal joint lining along with the loose pieces lowers the chance of the lumps returning. Results vary from person to person.
Can it go away on its own?
The lumps usually do not disappear without treatment. Some people have mild symptoms for years and do well with simple measures. Others need surgery for pain or locking.
Which joint is affected most often?
The knee is the most common joint. The hip, elbow, shoulder, and ankle can also be affected. The condition usually appears in only one joint.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
