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Q: Is it good or bad to crash your knuckles? ( Answered 4 out of 5 stars,   0 Comments )
Subject: Is it good or bad to crash your knuckles?
Category: Miscellaneous
Asked by: dopamine-ga
List Price: $3.00
Posted: 07 Dec 2002 14:50 PST
Expires: 06 Jan 2003 14:50 PST
Question ID: 121033
I always thought it was not good to crack ones knuckles.  But I just
had a professional massage and they cracked me all over and now I feel
great!  So what's the deal? Answer should site proof, not conjecture.
Subject: Re: Is it good or bad to crash your knuckles?
Answered By: shivreddy-ga on 07 Dec 2002 15:45 PST
Rated:4 out of 5 stars

Thank you very much for your question. The reason why kunckles crack
is actually not very well known. There are however two main theories
that are advocated by a majority.

1.Cavitation within the joint - small cavities of partial vacuum form
in the fluid then rapidly collapse, producing a sharp sound
(hypothesis in a medical journal)

2.The sudden stretching of ligaments (hypothesis by one reader of that
Cracking knuckles From Wikipedia, the free encyclopedia.

Theory 1:
The "cracking" of the knuckles results from forcing joint fluid to
very rapidly pass from one side of the joint to the other, where the
"sides" are partitioned off by the main bones of the joint.   A joint
is an area where two or more separate and distinct bones meet.  The
joint fluid provides a cushioning between the joints so that they
don't grate into each other.  Cracking your knuckles forces the joint
fluid from one part of the joint to another, and the cracking sound is
just the result of the high pressured rushing of fluid. Claims are
made that the high pressure flushing of fluid during a knuckle "crack"
can cause damage to the lining, but there simply is no evidence to
that effect.

Theory 2: 
"To produce the sounds, many people will bend their fingers into
unusual positions, or manipulate them in ways which are not commonly
experienced in everyday use. For example, bending the fingers right
back towards the back of the hand, or pulling them away from the
Cracking knuckles From Wikipedia, the free encyclopedia.

When the ligaments are stretched within the knuckle during this
manipulation, they tend to make noises like the ones we hear. This
theory is not very popular.

"Some people learn how to "pop their knuckles." By pushing or pulling
a joint in a certain way, an air bubble can suddenly appear in the
joint with a "pop." Once the bubble is there the joint cannot be
popped again until the air has been reabsorbed. Some joints crack as
the ligaments and tendons that pass over them slide past bumps on the
bones. Individuals who "crack their neck" make noise in this way..."
Frequently Asked Questions about Arthritis Edited by Frederick A.
Matsen, III, M.D. Last updated April 17, 2002

A lot of people say that knuckle cracking can lead to Arthritis. There
is simply no evidence to support this view. In fact a simple random
search using any search engine with the term " Cracking Kunckles" will
turn up with half a dozen front page hits saying that Kunckle Cracking
will NOT lead to Arthritis.

"There is no evidence that cracking one's knuckles can cause arthritis
directly. However, repeated injury of a joint or repeatedly causing it
to swell can injure the cartilage and potentially lead to degenerative
joint disease..."
Frequently Asked Questions about Arthritis Edited by Frederick A.
Matsen, III

Now what about Habitual Joint Cracking as in massages etc.?
"There has been very little work done to determine the long-term
effects of habitual joint cracking. The scant literature that is
available on this topic indicates that habitual knuckle cracking may
have a direct effect on the soft tissue of the hands and there is a
case study that indicates it may also cause damage that leads to
radiologic change. However, there is insufficient evidence to make any
conclusive statement regarding the long-term effects of habitual
knuckle cracking. The knuckle crackers had approximately 75% less grip
strength and a higher incidence of hand swelling. Because the average
duration of the knuckle cracking habit was 35 +/- 18 years, the habit
seems to have little effect on joint cartilage. The increase in joint
swelling and the decrease in hand function indicates that habitual
knuckle cracking has a greater effect on the soft tissue than on the
bone or cartilage. However, damage to the cartilage cannot be ruled

"...although habitual knuckle cracking does not relate to
osteoarthritis of the hand, it may relate to decreased hand function.
Therefore, habitual knuckle cracking should be discouraged..."
Knuckle cracking: key to a better life, or the road to a living hell?
An investigative report by Ian York

The above reference is an excellent paper on Knuckle cracking and
gives a detailed account of the habit and its consequences.

Now that we have authoritative sources in place, let us scan the
internet for more information. When I did that I came up an article
that should put things in the right perspective. An extract from that
article reads:
"Cracking your knuckles is another related noise [to the sounds made
when you wake up in the morning]. What you're doing here is pushing
the knuckle joint out of its normal position...This causes the
characteristic cracking sound of knuckles. You might think that this
is pretty harmless..."
"You'd be mistaken, though. You see, by cracking your knuckles, what
you're actually doing is pushing the joint beyond its normal range of
motion. That's entirely different from the painless cracking sound you
may hear each morning getting out of bed. This type of cracking puts
extra wear and tear on the ligaments (connect one bone to another
bone) and tendons (connect muscles to bone) that hold a joint
Mom was right -- cracking knuckles is bad

From the above analysis, articles and links it is rather obvious that
cracking knuckles is indeed bad. How bad it can be is a matter that
requires further research. That Cracking Kunckles leads to serious
bone related disorders is only a myth which so far has not been

Search Strategy:
cracking kunckles

That should answer your question. If you have any doubts please do not
hesitate to request for a clarification before rating this answer.

Thank you once again,

Warmest Regards,
Shiv Reddy

Request for Answer Clarification by dopamine-ga on 24 Jan 2003 23:49 PST
Thanks for the detailed answer.  I guess I should have phrased my
question:  "Is it good or bad to crack one's JOINTS" (not specifically
knuckles).  Neck, back,etc.  In other words, when stretching and my
joints crack is the okay, or to be avoided?  I always theard that
cracking was bad, but now with my stretch routine cracking is common. 
That's what I meant to ask.  Sorry for the confusion.

Clarification of Answer by shivreddy-ga on 27 Jan 2003 09:41 PST

The sound of cracking in the joints is caused primarily due to the
release of air pressure. Some rumours have it that this could cause
arthritis, but this is simply not true.

You might want to take a look at this reliable source:
"FACT: It's okay to crack your knuckles—or any other joint for that
matter. The cracking sound you hear is nothing more than fluid in your
joints shifting and gas escaping. Don't worry: It won't cause
Arm Joints (From the Rodale book, The Men's Health Guide to Peak

I hope this helps!

Warm Regards,
Shiv Reddy
dopamine-ga rated this answer:4 out of 5 stars

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