Ask The Experts

When pain and swelling in the knee persist

If painkillers and physiotherapy do not work, knee aspiration or keyhole surgery may help

Q My wife is suffering from pain in her right knee and has been diagnosed with osteoarthritis.

A magnetic resonance imaging (MRI) scan showed degenerative changes in her right knee, with moderate joint swelling and a torn meniscus.

She has been doing her physiotherapy faithfully and swims three times a week. However, the pain is still there and there is swelling in her right knee. She takes the painkillers prescribed by her doctor only when necessary.

Her scan also showed these problems - bone contusion of the medial tibial plateau and sprain of the right anterior cruciate ligament, and medial and lateral collateral ligaments.

Should she go for surgery?

A The swelling can result from knee effusion, which occurs when excess fluid accumulates around or in the knee joint due to a reactionary response of the inflammed joint lining, worn-out articular cartilage and the meniscal tear.

The articular cartilage is the smooth tissue that covers the ends of the bones.

The meniscus is another type of knee cartilage that acts as a "shock absorber". It is located between the thigh bone and shin bone.

The bits that are torn can interfere with knee joint movements, causing pain, swelling or "locking". The patient will be unable to straighten her knee normally.

A bone contusion of the medial tibial plateau means that there is a bone bruise in the upper knee joint. It could be due to a recent injury as it is a high-stress area of the knee joint. This can occur in those who are bow-legged, for instance.

A sprain of the right anterior cruciate ligament, and medial and lateral collateral ligaments refers to a spectrum of ligament injuries - from stretching to partial tears.

The MRI findings are important as they need to be correlated with the physical findings.

Your wife's doctor would likely have prescribed anti-inflammatory medications, which double as painkillers, and sent her for physiotherapy.

The latter comprises mainly quadricep and hamstring strengthening exercises to help prevent muscle atrophy and joint stiffness.

If the pain lessens within eight to 12 weeks, she should continue with her swimming and physiotherapy sessions.

But if the pain and swelling persist, a knee aspiration - which is a minor procedure to draw out the excess joint fluid - may help reduce the swelling. This involves taking out the knee joint fluid with a needle and syringe. A reduction of the knee swelling can sometimes reduce pain and help improve the range of motion in the knee.

Pain is a reaction to a torn meniscus. Some meniscal tears associated with arthritis can improve with time. Your wife may need surgery for the meniscal tear when the expected recovery time of, say, six to 10 weeks, has lapsed.

Some patients may benefit from surgical options to fix the tear.

One such procedure is knee arthroscopic surgery, or keyhole surgery, where a camera and working instruments are introduced into the knee joint via two or three small incisions.

This gives the surgeon a complete view of the knee joint, cartilage, menisci and ligaments. Depending on the state of the meniscal tear, it can be repaired, trimmed or smoothened out.

The small defects of the worn-out articular cartilage can be dealt with by smoothening the cartilage with the use of shavers or devices called radio-frequency wands. This is also done through keyhole surgery.

Some centres treat the cartilage defects by harvesting from a healthy area of the patient's joint for cartilage transplant.

The new cartilage cells are used to replace those that were lost to wear and tear in the knee joint.

But the outcome of such procedures has not been found to be consistent or durable in the long term.

Associate Professor

Tan Mann Hong

Associate Professor Tan Mann Hong is head and senior consultant in the department of orthopaedic surgery at Singapore General Hospital.


E-mail your question to Specify Ask The Experts as the subject and include your name, age, gender, identity card number and contact details.

A version of this article appeared in the print edition of The Straits Times on December 06, 2016, with the headline 'When pain and swelling in the knee persist'. Print Edition | Subscribe