What is lateral knee pain?
Lateral knee pain is a term that describes pain on the outside, or ‘lateral’, part of the knee.
The knee is a hinge joint that bends and flexes. In order to perform as intended, the knee relies on a number of supporting structures for stability including bones, ligaments, tendons, and cartilage. Pain can result when an injury or condition affects any structures in the lateral part of the knee joint or the surrounding tissue.[1]
Lateral knee pain is a common condition, especially in the older population but it can affect anyone at any age.[2] The symptoms of lateral knee pain can include a dull or sharp pain, stiffness, and reduced range of motion.
Acute (sudden) lateral knee pain can be caused by an injury, such as a torn ligament. Knee pain can also be caused by a chronic (slow onset) underlying chronic disease, such as arthritis or joint disease.
What are the symptoms of lateral knee pain?
The symptoms of knee pain may vary depending on the location, severity, and cause of the problem.
Common symptoms of lateral knee pain include:
What causes lateral knee pain?
Lateral knee pain has many causes, including injuries, muscular and skeletal problems, arthritis, and other conditions.
Some of the common causes of lateral knee pain include:
1. Iliotibial band syndrome
The iliotibial band (ITB) is a thick band of fibrous tissue that runs down the outer thigh between the hip bone and knee joint. Repetitive movement in the knee can cause friction and irritation of the ITB as it passes bony protuberances. When the ITB becomes irritated or inflamed, it is called iliotibial band syndrome (ITBS).
Symptoms are often experienced in the lateral knee, but can radiate up into the thigh or into the shin. ITBS is also called Runner’s Knee as it is commonly experienced by runners, but can also be seen in other sports where there are repetitive knee motions, such as cycling and jumping.[3]
2. Lateral meniscus tear
A meniscus is a crescent-shaped fibrocartilaginous structure in the knee. There are two menisci in the knee, the lateral meniscus (on the outer edge of the knee joint) and medial meniscus (on the inner edge). The role of the meniscus is to absorb load and reduce friction between the femur (thigh bone) and tibia (leg bone) in the knee joint.
The lateral meniscus can be injured during a sudden change of direction, especially a twisting motion when the foot is planted and when the knee is partially bent. Symptoms of a lateral meniscal tear often include a clicking sensation, reduced range of motion particularly when straightening the knee, a sharp pain, and difficulty walking.
This is a common injury in contact sports, such as football and basketball, and in sports that require frequent and sudden changes-of-direction, such as soccer or tennis. However, a lateral meniscus tear can also slowly develop over time with age.
3. Lateral collateral ligament injury
The lateral collateral ligament (LCL) provides stability to the knee, alongside three other major ligaments. The LCL connects the femur and tibia on the outer knee, and helps stabilise the knee by preventing forces from bowing and destabilising the knee.
Injury to the LCL may result from a knock to the inner knee that forces the knee outwards. If the LCL is stretched beyond its limits, it may result in a partial or complete tear. Common symptoms of an LCL injury include swelling, pain, and difficulty putting weight through the leg, and instability of the knee, the sensation that the knee might suddenly buckle or give out.
4. Osteoarthritis in the lateral knee
Osteoarthritis (OA) can cause lateral knee pain. There are two main compartments in the knee joint, the lateral and the medial. In some cases, there are more osteoarthritic changes in the lateral compartment, causing lateral knee pain.
OA is a common condition, particularly in older age groups.[4] Symptoms include stiffness, reduced range of motion, and a dull ache or sharp pain. The experience is often worse in the morning and may feel better with movement and walking. However, high levels of activity can often make the pain worse, especially at the end of the day.
Other causes of lateral knee pain
How is lateral knee pain diagnosed?
Lateral knee pain can be diagnosed by a health practitioner, who will take a detailed history and may complete a physical examination to determine the cause of pain. They may ask how the knee was injured, the location and type of pain, and the relevant personal and family history. They may also perform a series of manual techniques to assess the mechanics and movements of the knee.
Depending on the injury, your doctor may also request imaging tests to assess the bones and soft tissue structures in your knee, including:
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X-ray - An X-ray can give an image of the bones in the knee, and can help diagnose fractures, dislocations, and arthritis.
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CT scan - A CT scan gives a more detailed image of the bones in the knee, and can help diagnose complex fractures or deformities.
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MRI scan - This is used to obtain detailed images of the soft tissue in the knee, including the ligaments, muscles, tendons, and cartilage.
Based on this assessment, the doctor can diagnose the cause of the knee pain, which is important before a treatment plan is proposed.
In some cases, lateral knee pain requires immediate medical attention, including if there was a serious injury or accident, if the knee cannot bear weight, if there is marked swelling or unbearable pain, if the range is severely restricted, if there is any obvious deformity, or if there is a fever present.
How is lateral knee pain treated?
The treatment for lateral knee pain depends on the cause and severity of the pain. For minor lateral knee pain, conservative non-surgical treatments may be effective. However, major injuries to the meniscus or ligaments and advanced arthritis may require surgical measures.
Iliotibial band syndrome treatment
As ITBS is often caused by repetitive movements or running, a short period of relative rest can be beneficial. During this time, exercises that strengthen the muscles and stretches that help the flexibility of the ITB may help recovery. A physiotherapist can evaluate the biomechanics of the knee to prescribe the appropriate treatment and exercises. Once the symptoms settle, a physiotherapist can also check any running techniques and help develop a program to enable a gradual return to running.
Other treatment options include:
In some cases, your doctor may recommend a corticosteroid injection that may provide temporary pain relief and reduce inflammation.
Lateral meniscus tear treatment
Minor lateral meniscal tears may recover with a combination of conservative strategies including rest, pain relief, physiotherapy, compression, and occasionally a corticosteroid injection or bracing.
However, most meniscal tears do not heal on their own due to the limited blood supply to this structure. More severe tears may require surgery by an orthopaedic surgeon, who can repair the tear or trim away the damaged tissue.
LCL injury treatment
In the case of a LCL sprain or minor tear, surgery may not be required. A doctor may recommend conversative measures to help the ligament heal, such as adequate rest, bracing, pain relief, and monitoring. However, if the LCL is severely damaged, surgical input by an orthopaedic surgeon may be required.
Osteoarthritis treatment
OA is a chronic condition, and may require continued input and monitoring over time. Your doctor will likely recommend conservative treatments in the early stages. This may include:
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Strength training
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Aquatic therapy
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Lifestyle changes, such as weight or diet
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Assistive devices, such as a walking stick.
If the arthritis is advanced and is impacting quality of life and function, surgery may be considered. An orthopaedic surgeon may recommend a partial or total joint replacement. This is a major surgery, and recovery may be prolonged.
Can you recover from lateral knee pain?
Recovery from lateral knee pain depends on the cause of the problem. Shorter healing times may be adequate for milder injuries. Severe conditions or advanced conditions may require more time to heal, especially if surgery is required.
In the case of chronic lateral knee pain, the pain may never fully resolve and may need to be monitored and managed over time.
Things to consider about lateral knee pain
Lateral knee pain can be caused by acute or chronic conditions. The severity of symptoms vary, but it is common to experience pain in the outer part of the knee, stiffness, and decreased range of motion. Lateral knee pain can often be treated with simple conservative measures. In other cases, lateral knee pain may require a consultation with an orthopaedic surgeon.
It is important to see a health practitioner if you have any concerns about your knee pain, as it may worsen overtime if it is not treated in a timely manner.
