Knees are incredibly complex. Dozens of finely-tuned muscles, ligaments and sections of bone come together in a knee joint to provide those daily movements we all take for granted.
But, rather like fine pocket watches, complex objects with lots of moving parts can also run into problems. And where knees are concerned, that often means pain. So what are the most common root causes of a new, unexpected knee pain? Here are five possible options.
The number one cause of new knee pain is the most obvious one: an injury. You’re probably able to pinpoint exactly when it happened too – a fall on the stairs, a nasty sporting tackle, a sudden twist… Some of the most common knee injuries include:
- Fractures – a heavy impact can break the patella (kneecap), tibia (shinbone) or femur (thighbone)
- Meniscus tears – a rupture of the cushioning cartilage within the knee joint
- Ligament tears – a rupture of one of the tough tissues (ACL, MCL, PCL) that link the bones together
- Tendinitis – a stress reaction in one of the tissues that connects muscles to bones (eg the patella)
Injuries can cause various problems with the mechanics of your knee, too. Loose bodies are little bits of bone or cartilage that can break free and cause the joint to catch or lock. A patellar dislocation (or subluxation) is a kneecap that pops out of its natural alignment. In all these cases, the pain and symptoms can range widely depending on what you’ve damaged and how badly. So we may need to take some scans to investigate further.
This one is about a pain that’s caused by a new activity or change of routine. A classic example is a weekend DIY job involving lots of kneeling – the result might be something called bursitis, where the protective sac in the knee joint becomes irritated and swells up. Or a sudden change in the running regime – where tendinitis (see above) sets in over the coming days. Activity-related pain can also unmask a condition that has been present in your knee for some time – the final straw for a degenerate meniscus, for example, or for developing osteoarthritis. On which note…
This is what we commonly call “wear-and-tear” arthritis. It’s where the protective layer of cartilage on your bone endings becomes too thin, which causes the bones to grind against each other. Some typical symptoms of osteoarthritis include a dull background ache, pain following activity, and pain at night. People are often quite shocked to discover they have arthritis. Although the condition can take years to develop, the pain can come on quite suddenly – even when bone-on-bone arthritis has been present for some time. Why this happens is something of a mystery, but it often takes people by surprise.
4. Inflammatory arthritis
Some forms of arthritis are rooted in an inflammatory problem rather than wear-and-tear. The most common is rheumatoid arthritis. This is an autoimmune condition that can affect joints all over the body. It typically involves sudden flare-ups, which disappear and reappear. Unlike osteoarthritis, the pain is often worse in the mornings. Other common types of inflammatory arthritis are gout, pseudogout and septic arthritis.
Although rare, infections in knees are important to rule out because they can progress rapidly. You might think a knee infection would always start with an obvious cut on the knee, but in fact most transfer to the knee joint from somewhere else, through the blood. Something like athlete’s foot (a fungal infection) can cause a knee infection, or even teeth brushing. Infections can be viral or bacterial; viral tend to be more benign, whereas bacterial can become quite nasty. The red flags for infection are when the knee becomes hot, red, swollen, sometimes with a fever or a high temperature. If you think you might be suffering from a knee infection, it’s really important to see a doctor right away.
Are you concerned about a new pain in your knee and wondering what might be causing it? Please drop us a line today and book a quick appointment with Mr Bailey. You can call us on 01962 826107 – or book an appointment through the website.