Nine-year-old's joints make cracking sounds

Q. My grandson is nine years old, weighs 40kg and is 1.45m tall.

Recently, he has been telling us that when he stretches, his joints have cracking sounds. This includes the joints in his shoulders and wrists.

For instance, there are cracking sounds when he spreads his 10 fingers wide apart. The sounds also happen when he stretches his legs.

Does he need medical attention?

A. The sharp, cracking sounds made when joints are stretched is commonly due to the effect called cavitation.

There is a sudden decrease in pressure within the joint cavity and this alters the state of the joint fluid, creating a pop sound.

This effect is short lasting as the joint fluid resumes its normal state.

There is no pain associated with this condition.

Excessive cracking in many joints can be associated with laxity of the ligaments.

There is no evidence that regular knuckle cracking leads to increased osteoarthritis of the joint.

Osteoarthritis is a degenerative joint disease that is commonly caused by wear and tear.

In some cases, the cracking sound produced when a joint is moved may be due to a tendon gliding abnormally over a prominent bony surface, such as the hip or ankle.

This condition can result in pain from the inflammation of the tendon. In such cases, medical attention should be sought.

A clicking sound from the knee in children can be associated with an abnormal alignment of the kneecap or an abnormally shaped meniscus (the shock-absorbing cartilage) in the knee joint.

This condition can occasionally be painful and warrants further medical evaluation.

If your grandson experiences pain when he is stretching his joints, it would be advisable for you to bring him to an orthopaedic doctor for an examination.

DR ANDREW LIM Consultant at the division of paediatric orthopaedic surgery at National University Hospital

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