Running is on the rise. According to Sport England’s Active People Survey results over 2 million people a week participate in running and, it’s the second most popular activity for people doing 30 minutes’ exercise at a moderate intensity at least once a week.
So why are we a nation that loves to run? There are many reasons. Running is inclusive, cheap and accessible without the need to arrange a court or organise a team. Some people run to lose weight, to get fit, to keep healthy, to beat their personal best time or to have time out to think and once we’ve been for a run we experience runners high with the release of feel good chemicals.
But no matter whether you are a beginner whose muscles are not used to running or a highly experienced runner training for the upcoming London Marathon on 23rd April when you’ll join up to 50,000 other runners as they pound the streets to finish the 26.2 mile run, anyone can be affected by a running injury.
Common knee injuries due to running
The knee is the most commonly injured joint among runners. Damage to the structures inside and outside your knee joint can result in fractures, dislocations, sprains, and tears. Knee components susceptible to running injuries include:
- Articular cartilage - covers the ends of your shin bone, thigh bone and the back of your kneecap (patella).
- Ligaments – there are four ligaments including your anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) in your knee that connect your bones together.
- Menisci - two cartilage discs that act as shock absorbers and help to stabilise your knee.
- Tendons - connect your muscles to your bone.
Runners knee, also known as patellofemoral pain syndrome (PFPS), is knee pain associated with your patella or kneecap. It is the most common condition for runners. It’s thought to be caused by an imbalance in the muscles that support your knee, and mechanical errors that can cause poor knee tracking.
The main symptom is pain around your knee when you run. The pain can be dull or sharp and severe and usually worsens as the intensity of exercise increases.
Chondromalacia Patella (CMP)
Chondromalacia patella is damage to your articular cartilage. It is a chronic condition that causes your kneecap cartilage to soften and break down resulting in pain and inflammation. It is caused by overuse of the knee, alignment problems, injury or ageing.
Knee pain around the patella typically feels worse when going up or down stairs. It may be brought on by sitting (with the knees bent) for long periods.
Patellar Tendonitis (Tendinopathy)
Patellar tendonitis is generally an overuse and ageing injury that affects your knee. It is the result of your patella tendon being overstressed. A common name for it is jumper's knee.
Patella tendinopathy usually causes pain, stiffness, and loss of strength in your knee.
IT Band Syndrome (ITBS)
Your iliotibial (IT) band is a tendon that connects your knee to your hip. It helps to stabilise your knee.
IT band syndrome (ITBS) can occur due to overuse, overstrain and biomechanical factors. Your IT band tightens and becomes irritated and inflamed. The main symptom is pain on the side of your knee.
ACL and PCL injuries
An ACL or PCL tear is caused by overstretching the knee's ligament. It can occur when a runner stops suddenly, changes direction rapidly, whilst slowing down, landing incorrectly or has a direct collision.
You will feel pain and swelling around your knee. You might hear a popping noise and you may feel your knee give way from under you.
Prepatellar bursitis is an inflammation of your bursa (cushioning sacs between bones and soft tissues to reduce friction) in the front of your kneecap. Your bursa can become irritated and swell and then put pressure on your adjacent knee parts.
It can be caused by either repetitive friction on the area, muscle tightness, or from a sudden injury to the knee.
Your kneecap can be pulled to the side of (subluxation), or fully dislocate from, the groove it normally glides over in your knee joint. The supporting tissues can be stretched or torn when this happens. It can be caused by a blow or a sudden change in direction when you put your foot on the ground.
Your kneecap will look out of place and will be accompanied by knee pain, swelling and a popping sensation.
Medial Meniscus Tear
A meniscus tear is a tear to the cartilage in your knee joint causing pain on the inside of your knee.
The most common cause of a meniscus tear is twisting of your knee when your foot is on the ground. It can also occur through direct impact in contact sports and in older athletes through gradual degeneration.
A plica is a fold of the soft inner lining of your knee joint that can be more prominent in some people. Plica syndrome occurs when this lining of your knee joint is irritated and inflamed and causes knee pain.
Activities that repeatedly bend and straighten your knee, such as running can irritate the plica and cause plica syndrome.
Knee Stress Fracture
A stress fracture in the knee can be the result of increasing the amount or intensity of an activity, such as running, too quickly. Unfamiliar surface (path rather than grass), improper equipment (worn or less flexible running shoes) and increased physical stress (a runner increasing their running time) can also cause a knee stress fracture.
A stress fracture will cause you pain in your knee.
When to seek treatment for your knee pain caused by running
Most knee injuries in runners can be resolved by conservative methods such as rest, ice and stretching. If your pain is not severe but lasts for a week or more you should seek medical advice to have your knee checked over. Your GP or a physiotherapist will offer advice about exercises and stretched that will help your recovery.
However, if your pain is severe or your knee is swollen you should see a doctor straight away. They will ask about your symptoms and perform a physical examination of your knee. You may be referred to an orthopaedic surgeon for further investigations or treatment.
Diagnosing your knee condition
Your GP or orthopaedic surgeon may request the following tests to investigate further your knee pain:
- An X-ray or CT scan – to check for a fracture or arthritis.
- An MRI scan – to determine cartilage or soft tissue damage.
- Knee aspiration – to drain off fluid and help in the diagnosis of knee joint disease.
- Knee arthroscopy – your doctor looks inside your knee using a telescope and a tiny camera to see if there is meniscus, cartilage or ligament damage. Knee arthroscopy is minimally invasive surgery and can be used to treat your knee problem at the same time.
Treatment options for knee problems caused by running
Treatment will depend on your specific knee problem and your doctor will be able to advise you on the best course of treatment. Options include:
- Non-steroidal anti-inflammatory medication
- Exercise to strengthen and stretch your muscles
- Knee tape or brace
- Advice for footwear
- Surgery – some knee pain conditions will need surgery. This may include fractures, ligament tears such as ACL tear, removal of the plica, malalignment of the patella or, damage to the cartilage under your kneecap.A knee arthroscopy can be performed to wash out loose fragments in your joint caused by wear or to trim or repair torn cartilage and ligaments.