What is this cracking?
While many refer to it as cracking your joints, this is more formally known as crepitus. A cracking or popping that occurs with movement in a joint due to the presence of air in joint tissues.
What makes a joint?
Joints are made up of many different components, but at the most basic, a joint is the mobile area between two adjacent bones. Joints consist of the following:
- Tendons: joining the muscles to bones to provide strength, stability, and support precise motions while supporting a load
- Synovial fluid: bathes the space and tissues to reduce friction and lubricate the joints. This area can become inflamed or swollen depending on how many pro-inflammatory agents build up in the space.
- Articular cartilage: a smooth, frictionless tissue covering the ends of the adjacent bones to allow them to glide past one another seamlessly.
- Bursa: these small sacs are filled with fluid and provide a cushion between tendons, muscles, and the bones
- Muscles: these provide the motions of flexion and extension, but may be involved in a wider range depending on which joint is being discussed.
What are the symptoms?
Depending on the causes, the symptoms could be associated with swelling around the joints.
What are the causes?
More often than not, crepitus is generally considered to be harmless. However, there are times when it could be signaling a more severe condition.
- Arthritis. Conditions such as osteoarthritis cause the joint spaces to degenerate. This includes the cartilage which reduces the ability of the adjacent bones to glide past one another, creating friction, inflammation, and pain.
- Patellofemoral pain syndrome. This condition is characterized by pain around the knee cap (patella), and is commonly referred to as Runner's Knee as it represents over 16.5% of all running-related injuries. One study from 2018 demonstrated that women experiencing crepitus in the knees are four times more likely to experience patellofemoral pain syndrome.
- Trapped air. More often than not, the popping sound in joints is simply due to the rapid motion collapsing air bubbles that have accumulated in the joint space.
- Ligament/meniscus/tendon tear. It's possible to have experienced a tear in the tissues around a joint, and as they pass over bony joint structures, they can create sounds such as cracking or popping.
With all of these potential reasons, it's important to investigate the sound to rule out any conditions that require more aggressive intervention by your primary care provider.
Could it be harmful if I've got cracking all the time (i.e. cracking fingers)?
This is a myth that has been busted. Via x-rays, researchers demonstrated that there is no connection between cracking your knuckles and the gradual degeneration of the joint space. Good news for the children who were chided by loving family members for fear of damaging their fingers over time and ending up with arthritis.
What exercises should I use to prevent cracking?
It's important to focus on increasing the strength of your hip abductors and external rotators which prevent the knee from shifting towards the midline of the body while running and reduce crepitus. Muscles responsible for abduction of the hip include the tensor fasciae latae, the gluteus medius and minimus.
Muscles responsible for external rotation include the gluteus family (maximus, medius, and minimus), the gemellus superior/inferior, the quadratus femoris, and the obturator externus and internus.
These muscles can be strengthened by exercises such as side-lying leg lift, clamshell, fire-hydrants, prone extensions, and raised knee walking amongst others.
If there is pain associated with the sound, how can I manage it?
Devil's Claw: Harpagophytum procumbens, otherwise known as Devil's Claw, is a plant species native to south Africa. The harpagosides, the active constituent of the plant acts as an anti-inflammatory and can be taken internally. Products such as Joint Pain Relief tablets can provide this benefit, but the European Medicines Agency notes that it could take 2-3 months to notice significant benefits as the harpagosides accumulate in the tissues of the body with patients noticing decreased pain and increased joint mobility.
As you began to build muscle and add load to the bones, you may notice a decrease in the joint pain and could potentially reduce the dose of harpagosides. It's important to work alongside your primary care provider to minimize your risk of injury.
Turmeric: The active compound of turmeric is known as curcumin and makes up a large portion of the anti-inflammatory benefits of turmeric. These curcuminoids act on a pro-inflammatory signal known as NF- κB and reduce inflammation. Researchers saw a reduction in pain as indicated by a visual analogue scale, a decreased WOMAC score, and a reduced need for painkillers. Another interesting trial in 2019 demonstrated that curcumin was as effective as diclofenac for controlling pain associated with rheumatoid arthritis, a common non-steroidal anti-inflammatory (NSAIDs) which is slightly superior to other NSAIDs. While turmeric can easily be added to one's diet, you may not achieve the levels shown to be effective in the research. It's worth discussing which product may be best for you.
References:
https://bmjopensem.bmj.com/content/2/1/e000086
https://www.ema.europa.eu/documents/herbal-report/final-assessment-report-harpagophytum-procumbens-dc/harpagophytum-zeyheri-decne-radix_en.pdf
https://www.nature.com/articles/s41598-018-22664-4.pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1129752/pdf/westjmed00297-0049.pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5003001/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5664031/
https://www.ncbi.nlm.nih.gov/pubmed/29890402
https://www.ncbi.nlm.nih.gov/pubmed/30975196