Osteoarthritis: Imaging & radiological management options

Dr Amit Chakraborty, Feb 2019

Introduction:

Osteoarthritis is a chronic and debilitating condition which affects a vast majority of the general population. It takes a tremendous toll on a person’s ability to mobilise or use the affected body part. Nonsurgical management of osteoarthritis remains a challenging topic. Ongoing use of pain medication provides some relief although as the disease progresses, higher doses become necessary.

What is osteoarthritis?

Osteoarthritis is a degenerative condition of the joint whereby the internal components of the joint wear out over time. The cartilage coverage of the bony surfaces becomes thinner and eventually erodes away. This causes friction between the bones which then results in bony irregularity and degenerative changes. Overhanging bony outgrowths known as osteophytes develop and can restrict the movement of the joint. Because of loss of cartilage surfaces and bony irregularity, there is friction between the bones during movement, which causes pain. The joint space becomes narrowed which also contributes to the loss of function.

What causes osteoarthritis?

Osteoarthritis is a degenerative condition, and in most cases, it happens as a result of general wear and tear. Overuse of a particular joint may result in a higher degree of wear and tear and an early onset of osteoarthritic changes. Other causes include previous injury, haemorrhage within the joint, inflammatory conditions or previous infections.

What is the treatment of osteoarthritis?

The definitive treatment of osteoarthritis is joint replacement. However, it is a major surgical procedure and may not be suitable for individuals with chronic cardiorespiratory conditions. A joint surgery also involves a period of intense rehabilitation. Thus, mild to moderate forms of osteoarthritis are generally symptomatically treated with analgesia.

What your radiologist can offer:

A number of imaging techniques and image guided interventions are available for those with osteoarthritis.

Your doctor may refer you for a plain x-ray initially to determine if there is osteoarthritis. Plain x-rays are easy, simple and a quick way to image a joint and assess its overall condition. Your radiologist can often categorise the osteoarthritis as mild, moderate, or severe based on an x-ray alone.

Further imaging investigations such as MRI and CT scans are also very useful. A CT scan can examine the bones in greater detail. If a joint replacement is planned, your specialist may order a CT scan to accurately assess the bones and plan for the surgery.

An MRI examination can help to assess the bones as well as the soft tissue structures around the joint.

A number of symptomatic management options are also available radiologically.

1. Image guided corticosteroid injection within the joint:

This is a commonly performed procedure which is safe, effective and can result in significant functional benefit. It is generally done under ultrasound or CT guidance where a small dose of steroid mixed with local anaesthetic is injected within the joint. Steroid acts to reduce the joint inflammation and thus, improves pain and mobility.

This is safe and easily performed procedure can be repeated if necessary. A steroid injection within the joint can provide substantial pain relief for a few weeks and can help to reduce the amount of painkillers necessary to control the symptoms.

Risks:

There is a very small chance that you may be allergic to corticosteroids. Generally, a very small needle is used for this procedure. There is a small chance of bleeding within the joint. If you are on blood thinning medications, you will be asked to stop them beforehand.

Very rarely, the symptoms can worsen initially before getting better.

2. Image guided platelet rich plasma (PRP) injection:

A new, novel therapy that has emerged in the recent times where a person’s own blood extract is injected back within the affected joint. This promotes healing and can delay the progression of osteoarthritis.

It is generally safe and quite easily performed under ultrasound guidance.

For more information on PRP injection, please see our article here.

Post-operative imaging:

If you have had a joint replacement, your specialist will request radiographs at regular intervals to monitor the prosthetic components and their alignment.

Our radiologists bring years of experience and expertise in assessment and management of osteoarthritis and performing imaging guided steroid and PRP injections in all joints. They are also very happy to discuss details of this procedure with you and answer all your questions.

If you suffer from osteoarthritis, it may now be a good time to talk to your doctor to see if an image guided corticosteroid injection or PRP injection is suitable for you.