The cracking noise your knees make during exercise or normal movement is called crepitus. On Cleveland.com, Dr. Michael Roizen and Dr. Mehmet Oz say the cause of the condition is not always clear. However, crepitus is not usually serious and can often be treated by strengthening the muscles around the knee.
Your Knees
Of all the joints in your body, your knees are responsible for absorbing the most pressure and bearing the most weight on a continual basis. While it is strong, the knee joint is also particularly vulnerable to injury, according to the American Academy of Orthopaedic Surgeons. This is because of its complex design; it is made up of three bones, tendons, ligaments and cartilage. A number of common knee injuries and conditions are often accompanied by a popping noise.
About Crepitus
One possible cause of crepitus is osteoarthritis, which occurs when the cartilage that acts as a cushion between the bones in your knee joint wears away. As it deteriorates, your bones don't glide as smoothly over each other and can make a cracking noise. There is no cure for osteoarthritis, but gentle exercise can help ease the condition.
Gas in the knee joint is another possible cause of crepitus. Stretching a joint beyond its normal range of movement leads to a change in pressure in the fluid synovial fluid that helps lubricate the joint, as reported by West Coast Family Chiropractic. The gas forms bubbles; as they burst, the bubbles make a popping sound. Your knee tendons and ligaments snapping over the bones can also make a cracking noise. This is usually occurs if your ligaments and tendons have tightened up due to exercise, so gentle stretching can help.
Thigh Contractions
This exercise helps strengthen the muscles around your knee joints to ensure they are well supported and help absorb some of the pressure that's placed on them. Sit on the floor or a bed with one leg straight out in front of you; place a rolled-up towel under the knee. Tighten your quadriceps muscles at the front of your thigh as much as you can without causing any pain; gently push the back of your knee into the towel. Hold for five seconds, then relax and repeat this exercise 10 times.
Shoulder Bridge
This exercise strengthens and stretches your knee joints at the same time; it is particularly useful if your crepitus is due to tight tendons. Lie on the floor with your knees bent and your feet flat on the floor. Keep your arms down by your sides and lift your hips off the floor, as high as you can so your body forms a straight line from your knees to shoulders. Hold for five seconds, then gently lower your hips back down to the floor; repeat 10 to 20 times. Make sure you don't sag around your middle in the elevated position.
References
- Cleveland.com: Those cracking sounds during exercise might your body saying, 'Take it easy': the You Docs; by Dr Michael Roizen and Dr Mehmet Oz
- American Academy of Orthopaedic Surgeons: Meniscal Tears
- SportsInjuryClinic.net: Arthritis of the knee (Osteoarthritis)
- West Coast Family Chiropractic: Why Do My Joints Pop and Crack?
- SportsInjuryClinic.net: Strengthening Exercises
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