The quadriceps muscle in the thigh and the hamstrings muscle in the calf are the main muscles that act on the knee joint. The quadriceps muscle is responsible for straightening the knee, while the hamstrings muscle is responsible for bending the knee.

During movement, the knee joint is stabilised by the ligaments, which help to prevent excessive or abnormal movement. The ACL and PCL run diagonally within the knee and help to prevent the tibia from sliding out in front of or behind the femur. The MCL and LCL are located on the sides of the knee and prevent the tibia from sliding too far away from the femur.

The synovial membrane also plays a role in the knee joint biomechanics, it produces synovial fluid that lubricates the joint and helps to reduce friction and wear between the bones, it also helps to provide nourishment to the cartilage and other tissues in the joint.

Overall, the knee joint is a complex structure that requires the proper alignment and function of the bones, muscles, ligaments, cartilage, and other tissues in order to move efficiently and painlessly. Any injury or dysfunction in any of those structures can cause pain, instability, and limit mobility.

Ligaments are strong, fibrous tissues that connect bones to other bones and help to stabilise joints. The knee joint has four main ligaments: the anterior cruciate ligament (ACL), the posterior cruciate ligament (PCL), the medial collateral ligament (MCL), and the lateral collateral ligament (LCL). The ACL and PCL run diagonally within the knee and help to prevent the tibia from sliding out in front of or behind the femur. The MCL and LCL are located on the sides of the knee and prevent the tibia from sliding too far away from the femur. These ligaments work together to provide stability and support to the knee joint and help to prevent excessive or abnormal movement.

With a mild sprain, an individual may be able to walk or bear weight on the affected knee.

When partially torn,  swelling and pain may make it difficult to bear weight.  The joint may also be less stable.

If completely torn you’ll likely experience severe pain, swelling, and instability in the joint. The knee may give way or buckle, making it difficult or impossible to bear weight.

A proper diagnosis is important to determine the severity of the injury and the appropriate treatment. An MRI or an X-ray scan are usually used to determine ligament injury.

The knee joint has two types of cartilage: articular cartilage and meniscus.

Articular cartilage is the smooth, white tissue covering the bones’ ends in the knee joint. It helps to reduce friction and absorb shock in the joint. When articular cartilage becomes damaged, it can cause pain and stiffness in the knee and make it difficult to move the joint.

The meniscus is a crescent-shaped piece of cartilage that sits between the thighbone and the shinbone in the knee joint. It helps to distribute weight and provide stability to the joint. 

Damage to the cartilage and meniscus can happen due to injury, overuse, or age. In some cases, small tears or damage to the meniscus can heal on their own with rest and physical therapy. In more severe cases, surgery may be necessary to repair or remove the damaged tissue.  Regenerative repair techniques are developing all the time and could be possible depending on your age and level of damage.

When either the cartilage or meniscus is damaged you’ll likely experience pain, swelling and instability in the joint.  With a tear in the meniscus, you can sometimes experience ‘catching’ or ‘locking’ upon flexing the joint. 

The patella, also known as the kneecap, is a small bone located at the front of the knee joint. It sits in a groove on the front of the thighbone (femur) and is connected to the quadriceps muscle in the thigh by the quadriceps tendon.

The patella helps to protect the knee joint and also serves as a pulley for the quadriceps muscle, which helps to straighten the knee. The patella also increases the leverage of the quadriceps muscle, allowing the knee to extend more efficiently.

When the patella is not properly aligned in its groove, it can cause a condition called patellofemoral pain syndrome (PFPS), which can cause pain, stiffness, and weakness in the knee, often caused by overuse, injury, or muscle imbalances. In some cases, it can be treated with physical therapy and exercises to improve muscle strength and flexibility. In more severe cases, surgery may be necessary to correct the alignment of the patella.

Patellar dislocation is a condition that can happen when the knee cap slides out of its normal position. It’s usually caused by a trauma or a sudden change of direction. 

Mr. Farndon can advise on and treat issues around the Patella and Patellofemoral joint.

The synovial membrane is a thin layer of tissue that lines the inside of the knee joint. It is responsible for producing synovial fluid, which lubricates the joint and helps to reduce friction and wear between the bones. It also helps to provide nourishment to the cartilage and other tissues in the joint.

When the synovial membrane becomes inflamed, it is called synovitis. Synovitis causes pain, stiffness, and swelling in the knee joint. It can also lead to an increase in the production of synovial fluid, which can cause the knee to feel “full” or “tight.” Synovitis can be caused by injury, infection, or autoimmune diseases such as rheumatoid arthritis.  It is also often present in the onset of Osteoarthritis. 

Treatment for synovitis can vary depending on the severity.  It’s important to note that synovitis is not a specific condition but rather a symptom of an underlying problem, therefore it’s important to get a proper diagnosis by Mr Farndon to understand the route cause of the problem.