Most individuals experience knee popping every now and then, usually when climbing stairs. When climbing stairs, the movement stretches the tendons in the knees in a manner that produces the sound. If this occurs in an infrequent manner, it is usually harmless.
As for cases in which the knee popping is frequent or occurs along with pain, it might indicate an injury or degenerative condition that requires assessment by a doctor. Treatment is vital in order to prevent further injury.
Anatomy of the knee
The femur links with the tibia to form the knee joint. The patella or kneecap is a shield-shaped bone that rides over the joint for protection. The knees support most of the body weight and they are often subjected to significant stress.
There are 2 durable pieces of cartilage or menisci that are connected on either side of the knee that function as shock absorbers to cushion the bones as well as stabilize the joint. The knee popping can be linked to injury or deterioration of this cartilage.
Benign popping
The joints have synovial fluid which is a lubricant that protects the bones from injury. This fluid contains oxygen, carbon dioxide and nitrogen. If the knee is stretched such as climbing stairs, the gases escape rapidly from the joint and produce a cracking or popping sound.
When climbing stairs, the position of the tendons that surround the knee can be altered and the knee popping that occurs might be due to the movement of the tendons as they return to their normal position. Additionally, the soft tissue surrounding the knee can oftentimes move over the perimeter of the joint and the individual feels a pop as it moves back.
Injuries
Always bear in mind that knee popping is one of the indications of a tear in the meniscal cartilage. In younger individuals, it most often occurs during sports but as one starts to age and the cartilage thins out, engaging in any routine twisting movement can lead to a tear.
In most cases, the individual can still walk even with a tear, but there is pain and the joint stiffens within a few days. Swelling is also likely to occur. In case the injury is not promptly treated, part of the meniscus might come between the bones of the joint that can cause the knee popping. Once the individual experiences knee pain or experienced an event that resulted to a tear, a doctor should be consulted. The treatment typically involves rest, immobilization and even surgery as the last resort.
Aging process
If the individual has arthritis, the bone surface in the knee becomes rough over time. The combination of uneven bone surface and progressing thickening of the cartilage can lead to frequent knee popping.
If pain is also present, the doctor can provide relief by managing the arthritis symptoms. Cutting down on weight can reduce the stress on the knees while mild exercise can buildup flexibility to prevent injuries.