Knocking knees

Dr Aashish Chaudhry

Bones are tissues that continuously break and rebuild in tiny amounts. It is extremely important to keep the bones healthy. People who don’t have a healthy bone mass and can’t rebuild/replace the old bones with new ones during wear and tear are prone to osteoporosis. Called the brittle bone disease, osteoporosis is estimated to affect 200 million women worldwide. It affects over 10 million people in India each year.

Sometimes many people hear occasional sounds of popping, snapping, and crackles when they bend their knees. Other joints, too, might make these noises. They should be cautious as these sounds are common in joints with arthritis.

Any grinding, creaking, cracking, grating, crunching or popping sound occurs when moving a joint. Doctors call this sound ‘crepitus’. This term usually refers to the joints, but can be used to describe lung sounds as well. Over time gas can build up in the areas surrounding a joint, forming tiny bubbles in the synovial fluid. Sometime when you bend your knee, some of the bubbles burst, and ligaments may make sounds like popping and snapping. This is normal and happens to everyone from time to time.

As you get older you are more prone to crepitus but it can happen at any age. It is known that arthritis damages cartilage and bones. As the damaged knee joint moves, it may crackle and crunch.

A joint is where two bones come together. Bones are covered with protective tissue called cartilage where they end. With OA, this cartilage breaks down, causing the bones within the joint to rub together. This causes pain, stiffness and other problems.

OA often occurs in older people, although it can occur in adults of any age. OA is also called degenerative joint disease, degenerative arthritis and wear-and-tear arthritis.

Knee crepitus is one of the common symptoms of osteoarthritis (OA), a chronic joint condition. It can also be one of the symptoms of rheumatoid or infectious arthritis and may accompany several different types of knee injuries. So, if your knee creaks, crackles and/or hurts, please visit an orthopaedic as soon as possible.

Crepitus in the knees may also be caused by knee injuries such as meniscus tears. These tears are common in sportspersons, or those who run or jog.

Chondromalacia patella is a dull ache behind the kneecap, usually caused by overuse or injury. There will be damage to the under-surface cartilage covering the kneecap.

Patellofemoral syndrome, or runner’s knee, is caused by a force overload on the patella that occurs before there is actual damage to the joint surface of the patella. This syndrome can lead to chondromalacia patella. If you have chondromalacia patella, you’ll feel and hear a painful crunching and grating when you move your knee.

Other knee injuries and types of arthritis can also cause crepitus. Crepitus usually is not a cause for concern. In fact, most people’s joints crack or pop occasionally, and that is considered normal. But if crepitus is regular and is accompanied by pain, swelling, or other symptoms, it may be an indication of arthritis or other degenerative diseases and disorders.

Excess weight hinders growth in children

Bones grow in size and strength during childhood. Too much weight can seriously impact the growth and health of bones, joints and muscles, especially among children. Extra weight can damage the growth plates — the area at the end of the body’s arm, leg and other long bones where the cartilage tissue develops. Growth plates regulate the length and shape of a bone at full growth. Too much weight places excess pressure on the growth plate, which can lead to early arthritis, a greater risk for broken bones and other serious conditions. Studies suggest every kg of additional weight exerts close to 1.8 kg of extra pressure on the knees. For instance, if a person is 10 kg overweight, his knees will have 18 kg of extra pressure.

Cut down alcohol, smoking and caffeine

Too much caffeine hinders with body’s capability to absorb calcium, decreasing bone mass in the process. So, reduce your alcohol, smoking and caffeine intake.

Bones are the basic frame on which the whole of body rests, keep them healthy.

For good bone health, exercise

Running, yoga and other exercises can help in maintaining weight, lowering cholesterol levels and reduce stress and depression. Regular exercise helps in boosting immunity, maintains bone strength and improves joint function, keeps weight in check, good for the heart, lungs and brain and improves overall quality of life.

Be aware of your calcium and vitamin d levels  

Indians are more at risk of developing the disease due to low peak bone mass, poor calcium and vitamin D deficiency. It is a misconception to think that age is the only risk for osteoporosis. If we do not take adequate calcium packed diet, including dairy products and vitamin D supplements, osteoporosis will set in quite early.

Other Joints

Shoulder popping and cracking: People assume these may happen because of some injury but these sounds could indicate early onset of some new serious problem. If cracking/ popping is accompanied by pain, do see a doctor. Treatment includes physiotherapy which can fix these movements, realign the joints, reduce or improve the symptoms and popping sounds. 

Neck cracking and grinding: Cracking, popping, snapping and grinding can occur in the neck as well. It is usually painless and there is nothing to worry. But if these sounds are accompanied by pain it could indicate cervical osteoarthritis or some other problem. If there is pain and swelling and problem in turning or moving the head along with these sounds, it indicates some medical problem. If sounds happen after an accident or injury, see a doctor immediately. Also if these are frequent and constant even with normal movements, there may be a problem in function of the joint. 

Hip clicking and snapping: This sound emanates as snapping, flicking and clicking of the bony parts of hip joints. This is often painless but if accompanied by pain, it can indicate inflammation, bursitis and other problems like snapping hit syndrome which is common in dancers, athletes and people doing a lot of exercises. Consult a doctor if the pain and sounds persist. Hip exercises and yoga under expert guidance can help.

— The writer is an orthopaedic surgeon, Aakash Healthcare Super Specialty Hospital, New Delhi