Pain on the inner side of the knee is probably the most common kind of knee pain there is. You’ll often hear it called medial knee pain – medial simply meaning “middle”, since this part of your knee is situated towards the middle of your body.
Most knee pains are mild and clear up naturally. But persistent or recurring knee pain needs to be investigated. And the location of the pain gives us an early clue about what might be causing it.
So what are the biggest causes of persistent inside knee pain? Here are some possibilities.
With an estimated 10 million sufferers in the UK, arthritis is one of the most common medical conditions there is. And osteoarthritis is the most common form of it. It’s where the hard cartilage covering on bones wears away, leaving the bone endings to rub against each other. Osteoarthritis in the medial joint compartment could certainly cause inside knee pain. It’s usually an insidious, background discomfort that becomes a dull ache over time, especially at night or after activity.
The meniscus is a shock-absorbing pad of cartilage inside the knee joint. When put under severe pressure – usually a sporting accident or, in older people, through wear and tear – the cartilage can rip or become damaged. You would generally feel it as a sharp, intermittent catching pain. You might also experience locking of the knee, where frayed tissue catches in the joint and prevents your leg from bending or straightening properly.
Chondral cartilage is another type of shock-absorbing material found in knee joints. It lines the ends of your thighbone (femur) and shinbone (tibia), helping to reduce friction. Like meniscal tears, you can damage this cartilage in an accident, often alongside another injury such as an ACL tear (see below), or through longer-term wear and tear. The symptoms can range from stiffness and swelling to locking. You might feel a sharp pain after twisting, or discomfort after a long walk or climbing a flight of stairs.
Read on: Knee Conditions: chondral injuries
A plica is a fleshy fold of tissue in the knee joint lining (the synovial membrane). Plica syndrome is what happens when this fold becomes unusually thick, normally after a sudden impact injury or through overuse (e.g. a new running regime). Although it’s sometimes symptomless, pain from plica syndrome usually occurs on the inner side of the knee. This will often happen after 10-15 mins of exercise, or perhaps after squatting, kneeling or walking up and down stairs.
Bursitis is a condition that can affect joints all around the body, not just the knees. It’s where one of the bursae – the thin sacs that provide cushioning protection to the joints – becomes irritated and fills with fluid, causing the knee to swell up (sometimes quite alarmingly). This usually happens after a repetition injury, such as kneeling on a hard surface during a DIY project. Alongside the swelling, you might experience stiffness, redness, tenderness – and pain on the medial side of the knee.
MCL / ACL injury
Knee ligaments act as guy ropes within your knee joint, pulling the structure into a strong formation that gives you stability. Unfortunately, it’s quite possible to damage these ligaments through trauma – usually a major impact or a sporting accident. A torn MCL (medial collateral ligament) causes swelling and sharp pain on the inner side of the knee, often with a popping sound at the point of impact. A torn ACL (anterior cruciate ligament) can cause similar symptoms if the damage is towards the inner part of the ligament.
Osteonecrosis – also known as avascular necrosis – is a relatively rare condition where the blood supply to the nearby bone becomes disrupted. With inner knee pain, that’s likely to involve the medial femoral condyle, a projection at the bottom of the thighbone. Unlike many of the above conditions, it’s usually not related to accident or injury. The pain tends to come on quite suddenly at first. Over time it can become hard to move the knee, or put weight on it, without pain.
Although the causes of inside knee pain can be quite varied, the important thing is to get yourself checked out if the pain is unusual, persistent or causing you real discomfort and worry. As we mentioned, most pains in the knee joints clear up by themselves. Sometimes, though, they’re flagging a more fundamental problem. When that happens, an early diagnosis is the best way forward.
Are you suffering from ongoing knee pain? We’re here to help. Please get in touch with us on 01962 826107, or book an appointment directly on our website. We’ll make sure you’re seen, examined and treated as soon as possible.