Knee Osteoarthritis

Osteoarthritis (OA) of the knee is a type of arthritis in the knee which is a degenerative condition where the cartilage between the end of the thigh bone and the top of the calf bone wear away, which cushions the impact on walking. It also produces a natural lubricant to help the joints glide smoothly thus the loss of cartilage will force the bones to rub painfully against each other, leading to inflammation and pain. Swelling, stiffness and pain are the common primary symptoms of someone with an OA knee.

There are three key factors that leads to OA knee developing:

Aging

In Singapore, OA knee usually affects the older population as our cartilage naturally thins as we age. However, degeneration may set in much earlier if you suffer from a previous knee injury or have a long history of activities that overloads the knee joint. Unfortunately, these events are irreversible, thus it is crucial that our knees are properly looked after during our early adult life.

Physical Attributes

There are several physical attributes that increases your chance of developing knee OA:

Obesity

Due to the excess weight, a heavier person will load their knee joints more and wear out their cartilages quicker. According to the Johns Hopkins Arthritis Center, for every 10 pounds of extra weight you carry, an additional 30 to 60 pounds of force is placed on the knees with each step taken.

Knee alignment

A knock-knee or bowlegged alignment will cause an uneven compression of the knee as the weight is not distributed and spread evenly on the joint. Unlike normal knee alignment which bears more body weight on the inner aspect, there is more strain placed on the outer knee ligament due to bowing of the knee and weight bearing. This increases the likelihood of knee sprains and discomfort.

Foot type

People with flat feet or whose feet overpronate tend to have their lower leg rotate inwards when the ankle rolls in the same direction. This places extra forces and weight on the knee, and excessive occurrence can affect the alignment of the knee. It will also lead to extra strain and rubbing on the knee joint, resulting in pain. The wrong type of footwear, such as high-heel shoes, can also contribute to degenerative changes to the knee.

肌肉发达的原因

The knee joint will take up the remaining forces of the impact of walking or running when the muscles around the knee do not contract strong and fast enough in a coordinated manner.

Weak muscles. The quadriceps comprise of a four-muscle group that are the strongest and leanest in the entire body. They support the weight of the body under regular use. Because it performs the majority of the work to extend the knee, it is very common for this muscle to atrophy due to disuse. The knee pain deters the patient from loading the knee and this will gradually lead to weakness of the knee which will affect the ability to cushion the impact. Without treatment, this cycle of pain, disuse, and weakness will continue.

Tight muscles. Tightness in the muscles and tendons pull joints closer to each other. In an OA knee where the joint space is already reduced, tight muscles change how forces go through the knee and increases the compression of the joint space. Such muscles also lack flexibility and limits the amount of movement at the knee, as well as be less coordinated. Muscles that tend to tight are hamstrings, quadriceps and calves.

The glute medius muscle also plays a key role in moving your hips, keeping the hip joint stable and steadying the pelvis. If the muscle is weak, it can aggravate the degeneration of knee cartilage and affect the lower limbs to be unstable. This results in more weight placed on the knee joints, causing discomfort and pain.

The best treatment for knee arthritis may involve seeking a specialist in physiology for treatment. This includes physical therapy that can help to reduce the pain, stiffness and swelling of knee osteoarthritis as well as improve knee joint function. Located in Singapore, our team at Core Concepts will work with patients in a multi-specialty setting to create a customised treatment plan best suited to your needs so you can increase your daily activities and restore your health in the long run.