Steroid Injection for Knee Joint Meniscal tear

A meniscal tear is a knee injury involving a tear to the tough and rubbery cartilage in the knee called the meniscus. It can be due to age (degeneration) or injury (trauma). 

Meniscal tears come in various shapes and sizes (see image below).

Causes

Meniscal tears are commonly caused by:

• Twisting or rotating the knee while the foot is planted, often during sports or physical activities.
• Deep squatting or heavy lifting.
• Ageing and degeneration of cartilage in the knee, making it more prone to injury. Degenerative tears are usually seen in those who are middle-aged (>40 years old), where the tear occurs due to gradual wear and tear of the cartilage (Buchbinder et al,  2016).

Symptoms of knee joint osteoarthritis

• Knee pain on the inner side of the knee joint – if a medial meniscus tear, or the outer side of the knee joint – if a lateral meniscus tear.
• Swelling may occur a few hours after an acute injury.
• Difficulty fully bending or straightening the knee.
• Catching or locking of knee

Anatomy

The meniscus comprises two crescent-shaped pieces of thick, rubber-like cartilage in the knee joint between the femur (thigh bone) and tibia (shin bone). One is located on the inner side of the knee (medial meniscus) and the other is on the outer side of the knee (lateral meniscus). It helps by acting as a shock absorber, distributes weight evenly and provides stability to the knee.

The meniscus typically has a limited blood supply.  The outer third is known as the “red-red zone” and has the best supply, the middle third is known as the “red-white zone” and has a moderate blood supply, the inner third of the meniscus is known as the “white-white zone” which has no direct blood supply.

How to diagnose

A thorough examination by the physiotherapist including detailed questioning and a physical examination of the knee.

Very peripheral tears can occasionally be seen on ultrasound scan. There are other signs of meniscal pathology that we can see on ultrasound scan and if we see these signs, we may suggest further imaging is required. 

An MRI scan would be required to find out the location of the meniscus tear and what type of tear that’s occurred.

Treatment

A study by van de Graaff et al (2022) compared outcomes of physiotherapy treatment or arthroscopic partial meniscectomy for the treatment of traumatic meniscal tears in the young population. They found that at the 24-month follow-up, the outcomes were the same in both groups. 41% of the physiotherapy group opted to have a delayed arthroscopic partial meniscectomy and still had the same outcome as the physiotherapy and early operation group.

Sihvoven et al (2020) also found that having surgery for degenerative meniscus tears is no better than a placebo operation.

Another recent study by Damsted et al (2024) compared rehab and surgery treatment for those with knee pain due to a traumatic or non-traumatic meniscal tear. Patients were aged between 18-40 years old and included all types of meniscal tears except complex and displaced meniscal tears. It found no significant differences in outcomes in both traumatic or non-traumatic meniscal tears if they had surgery or rehab.

It is also important to note that any type of surgery for any meniscal tear will lead to greater risks of knee arthritis after (Persson et al,2018).

Knee Meniscal Tears and Injection therapy

If symptoms do not improve with conservative treatment then an injection may compliment your Physiotherapy treatment. 

Two types of injections that may be used alongside physiotherapy treatment are hyaluronic acid (HA) injections and steroid injections.

Ultrasound-guided Hyaluronic  acid  injection

Hyaluronic acid is a naturally occurring substance  in the body and is found in high concentrations in the skin, connective tissues, and eyes.  Hyaluronic acid is then injected into the knee joint under ultrasound guidance to help supplement the synovial fluid, improving the knee joints lubricating and shock-absorbing properties. By restoring the viscosity and cushioning  of the joint fluid, the injections can reduce joint pain, improve joint mobility, enhance tissue health and reduce the need for subsequent surgeries like an arthroscopic partial meniscectomy (Berton et al, 2020)

Some  studies  suggest that  hyalauronic aciid  injections into the knee joint,  promotes tissue healing in the meniscus  (Mazy et  al,2024).

Dong et al (2023) found that arthroscopic surgery combined with HA injection, has better results than arthroscopy alone. There were better outcomes  on relieving joint pain, improving joint function and mobilitiy with no increase of compliciatiions.

Ultrasound-guided steroid injections

Steroid injections have strong anti-inflammatory properties and used to reduce pain and inflammation in the knee joint. It is injected into the knee under  ultrasound guidance. The injection doesn’t repair the meniscus itself, but it reduces pain, swelling, inflammation and stiffness (Wilderman  et al, 2019). 

The relief is short-term and can last from a few weeks to several months depending on the severity of the tear and individual response. The goal for a steroid injection is  to manage symptoms while allowing the  body to heal  and delay further invasive treatments, such as surgery. It may provide a window of opportunity for you to perform your rehabilitation and break the inflammatory cycle. 

Other Knee Conditions:

• Patellofemoral Pain Syndrome
• Iliotibial Band Friction Syndrome
• Knee Arthritis