Knees are something of a hot topic in the studio at the moment. I thought you might benefit from understanding their anatomy, typical problems, why they occur and tips for maintaining knee health.

Knee Anatomy

The knee is one of the largest and most complex joints in the body. It is a synovial joint which connects the femur (thigh bone) and the tibia (shin bone) in the lower leg (tibiofemoral joint). The fibula (calf bone), the other bone in the lower leg is connected to the joint but is not directly affected by the joint action. There is a second joint where the knee cap meets the femur ( patellofemoral joint). These two joints work together to form a modified hinge joint that allows the knee to bend and extend, but also rotate slightly from side to side.

Within the knee joint, the two knobbly ends of the femur are covered in articular cartilage. Also within the knee joint, the top of the tibia is made up of two plateaus which are covered in articular cartilage. Attached are two concave pads of shock-absorbing cartilage, called menisci, which minimise the  friction created at the meeting ends of the tibia and femur. The patellar tendon attaches the knee cap to the tibia, it is a continuation of the quadriceps tendon.

The patella (knee cap) is a semi-flat triangular bone that is able to move as the knee bends. Its main job is to increase the force generated by the quadriceps muscle, which straightens/extends the knee. Its other job is to protect the knee joint from trauma. The knee cap glides within a groove formed between the knobbly ends of the femur.

Four key ligaments connect the bones in the knee, they work together in controlling the stability of the knee:-

Muscles Around the Knee

Two main muscles groups keep the knee stable, well aligned and mobile.


Bursae are fluid filled sacs that cushion a joint by reducing friction between muscles, bones, tendons and ligaments. There are around 13 of these, in varying sizes, in and around the knee. Sometimes, whether due to direct trauma, or infection, these can become irritated, swollen and painful, a condition known as bursitis.

Problems in the Knee

Our knees are vulnerable to injury because they bear an enormous amount of pressure whilst providing flexible movement. Consider the load whilst performing these activities:

As you can see, there are many structures associated with the knee where problems can occur. Symptoms can vary depending on whether it is a wear and tear issue or an injury. Ligament injuries tend to lead to instability in the joint, whereas arthritis tends to decrease the range of motion. Swelling, the accumulation of too much synovial fluid, is usually due to irritation or inflammation of structures within the knee. Bleeding in the joint can also cause swelling, such as immediately after an injury. Best dealt with by REST – ICE – COMPRESSION – ELEVATION (R.I.C.E)

Another common condition is Runner’s Knee, but it isn’t only runners that suffer from this. This condition covers a broad range of problems; symptoms include pain in the front of your knee cap, but can also be around or behind it; pain when you bend your knee or walk down stairs or downhill. Clinicians call it Patellofemoral Syndrome and it can be caused by:-

Keeping your Knees Healthy

If you suffer from Arthritis avoid standing on hard surfaces for extended period of time. Also avoid deep bending of your knees and high impact sports such as jogging or anything that involves jumping. Instead go for low impact exercise like cycling, swimming or using an elliptical trainer.