Cheerful seniors stretching their legs while talking about why cartilage is slow to heal

Why Is Cartilage Slow To Heal?

We don’t often think about the state and health of our cartilage. That is, until it’s a problem for us. Then, a very common question gets asked: Why is cartilage slow to heal? And specifically, why is cartilage slow to heal compared to other parts of the body? 

Often, cartilage healing time is longer than the healing time for tendons, bones, or even ligaments. But why is that the case? And how long does it take for cartilage to heal, exactly? 

To understand cartilage healing time, we will need to delve a bit further into the wound healing process. This can be a tricky subject, so we’ll break this complex science into a step-by-step approach.

If you’re currently going through recovery and the frustration of not being totally mobile again questioning cartilage healing times, we’re here to walk you through the process and offer advice on how to support your healing.

Before we can directly answer the question “why is cartilage slow to heal?” we need to understand what cartilage actually is

Understanding cartilage

It’s easy to understand why cartilage is slow to heal once you learn a little more about cartilage itself. So let’s examine the details about cartilage. Where is it found in the body? What is its function? And how is it made?

Where is cartilage in the body?

You’ll find cartilage in almost any location of the body where two bones meet. It’s also at the ends of all your bones that form joints. 

Why do we have cartilage?

All bones need some cushioning. We want them to connect to each other, but we don’t want them to rub against each other – because that would wear them down and be very uncomfortable.

Bones are strong and rigid. Cartilage is strong but flexible connective tissue. 

Cartilage covers the ends of bones, creating a low-friction environment and cushion at the joint surface. Cartilage allows the body to soften the impact of heavy movements such as running or jumping. When cartilage in our joints is healthy, it protects the joint against weight-bearing stresses.

So cartilage needs to be strong and flexible to carry out these functions successfully. For that reason, it’s made from a special protein with those exact characteristics.

What is cartilage made of?

Like many parts of the body, cartilage is made from collagen protein.

Collagen protein is the most abundantly found protein in the human body. From ligaments to bones, organs to blood vessels, collagen helps strengthen and build resistance.

So it’s no surprise that collagen is the main building block of cartilage. Specialized cartilage cells produce a matrix of collagen, along with other proteins. These biomaterials help cartilage attract water and give it its shape and specific properties.

A continual supply of collagen is needed to keep cartilage ready to do its job.

Why is cartilage slow to heal? 

Cartilage is built tough to reduce the risk of injury, but it can be said that this tough makeup also results in slower cartilage healing times. In other words, slow recovery times are a tradeoff of being so strong to begin with.

Let’s take a look at some other reasons why cartilage is slow to heal. 

Why is cartilage slow to heal?

One of the main reasons why collagen is so slow to heal is that it is avascular. This means cartilage doesn’t have a traditional blood supply.

To specialize in doing its job properly, cartilage doesn’t contain nerves or blood vessels.

Blood vessels don’t have the same tensile strength properties as the rest of the cartilage collagen that would surround it. Put simply, the blood vessels would break. Because of this, there isn’t a traditional blood supply in cartilage. 

How can cartilage function without a blood supply?

Each part of the body requires some connection to the blood supply, because the circulatory system transports resources around the body for cells to use. So how does cartilage survive when it’s avascular?

Well, cartilage does have a blood supply of sorts. It just isn’t typical, or as efficient, when compared to the rest of the body. Blood isn’t brought to cartilage via blood vessels. Rather, fluids diffuse through the cell matrix of cartilage slowly, bringing with them the resources that cartilage needs.

Let’s explain how this works, because it’s central to answering the question: Why is cartilage slow to heal?

Nutrition to cartilage is maintained by fluid from the joints nearby. That lubricates the tissue. The lubrication process takes place by a type of flushing mechanism, when load is applied and then removed from the tissue repeatedly. 

Imagine spilling water on a cushion – it will spread out slowly across the stuffing. Repeatedly sit on the cushion and you will increase the speed at which the water travels through it. Imagine this water as fluid, carrying nutrients throughout the cushion. This is the same way liquids travel through your joints.

This system isn’t as effective as a strong blood vessel network, but as we’ve displayed; a traditional blood vessel network isn’t strong enough to function inside cartilage; so this method gets the job done.

What does it feel like to injure cartilage?

Interestingly, it doesn’t feel like anything at all! Cartilage is aneural, which means that it doesn’t have a nerve supply. 

Nerve cells are delicate, and their presence in cartilage (an impact zone for bone movement) wouldn’t be advantageous to the human body. Although nerve cells are microscopic, the body considers it more useful to pad out cartilage with collagen, proteins, water, and nothing else.

How do you know you’ve injured cartilage if it has no nerve supply?

You don’t feel cartilage being worn down from the cartilage itself. Rather, you only notice a lack of cartilage after it has worn down to the point where it can’t cushion the impact of bones on each other effectively anymore. That’s when you feel it. 

You learn about a cartilage injury not from nerves in the cartilage itself (because there aren’t any), but from nerves in the surrounding area from other cells. 

You can definitely consider cartilage is one of those things that you don’t know what you’ve got until it’s gone. That's yet another reason why cartilage is slow to heal – you may not realize you’ve damaged it until the damage is extensive.

By the time you’re reaching for the knee joint pain relief, you’ve already done a number on your cartilage and surrounding tissues. 

So, how DOES your cartilage heal? And what about it being avascular makes healing take such a long time? Let’s take a look at wound healing in the body. 

How does wound healing work?

Knowing why cartilage is slow to heal also involves us examining how the body normally handles wounds.

The wound healing process is a joint effort from many bodily systems. Wounds are a cause of concern not just because of the physical damage to the body, but because they present an opportunity for infections to occur.

It’s for that reason that the body acts quickly when a wound occurs, producing a scab and preventing as much blood loss as possible. Underneath the scab, before the damaged collagen tissue can be reconnected again, the immune system has to check for infections. It’s at this time that swelling occurs at the site of the wound, in an attempt to contain it.

Once the damaged or infected tissue has been cleared away, reconstruction can begin. The collagen fibers are woven back together and then reinforced layer by layer until all that is left is a scar at the site of the wound.

Although a scar doesn’t have the same strength as before the injury, it’s an incredible feat that the body can regain so much of the tensile strength that it once had before the wound happened.

If you’re worried about a wound not healing, then the reason may be an infection at the wound site that’s preventing healing from taking place. Alternatively, you may be suffering from a collagen deficiency and your body simply doesn’t have the nutritional resources that it needs to put itself back together.

There are a variety of slow healing wounds causes, so it’s important that you seek professional medical help tailored specifically to your situation if you have concerns about a wound you may have not healing how it should.

But compared to this general model in other parts of the body, why is cartilage so slow to heal?

Understanding how cartilage heals

It’s time to put all the pieces together to answer the question: “Why is cartilage slow to heal?”

So why is cartilage slow to heal? Cartilage healing time is slower because of a slower blood supply. It simply takes longer for the circulatory network to supply cartilage with the collagen resources it needs to reconstruct the damage, when compared to other parts of the body.

Exactly how long does it take for cartilage to heal? Let’s examine the healing time of cartilage compared to ligaments, bones, and more. 

How long does it take for cartilage to heal?

To help demonstrate how and why cartilage is slow to heal, here’s a handy reference table:

Typical tissue healing time frames

Tissue types:

Range of time for healing:

Muscle

2-4 weeks

Tendon

4-6 weeks

Bone

6-8 weeks

Ligaments

10-12 weeks

Cartilage

~12 weeks

Nerve

3-4 mm/day

 

It should be noted that healing time frames should only be taken as a general guide. The cause, size, and situation of each injury is unique. So too are the patients that suffer from them. 

Age, general health, and pre-existing conditions are all significant factors in calculating a wound recovery estimate, and all these factors can be influencing why cartilage is slow to heal for you or a loved one.

For the most accurate responses, it is best to speak with a medical professional who knows your individual case.

That being said, no matter why your cartilage is taking such a long time to heal, there are ways you can speed that healing up. 

Tips to speed up cartilage healing times

Now you understand why cartilage healing is so slow, but how can you support cartilage recovery?

One of the best things you can do for cartilage injuries is gentle exercise.

A lack of movement or weight-bearing can cause cartilage to thin, making it more susceptible to injury. Therefore, even fairly soon after an injury, gentle exercises may help the joint surfaces to heal. Over time, the load and stress on the joints can increase as the healing gets stronger.

Not doing exercises may be a reason why cartilage is slow to heal in your situation. Speak to a medical professional to learn about the specific range of movement related to your injury.

Also key to recovery is giving your body appropriate amounts of rest and nutrition.

Here are some general wound healing tips:

  • Rest well and perform limited movements to not aggravate an injury

  • Maintain a good diet (instead of eating less while resting - you may need to eat more)

  • Keep hydrated

  • Don’t add pressure on wounds unnecessarily

  • Keep the wound site clean, but without using harsh chemicals

  • Keep up a good level of collagen in your diet, or through supplementation

Not paying attention to each of the elements on this list could be why cartilage is slow to heal for you or a loved one, so it’s worth ensuring that you’re following all the recommended guidelines.

Take collagen supplements to promote cartilage healing

Now we know the key role collagen protein plays in cartilage composition, as well as so many other locations in the human body, there’s extra motivation to make sure our body has plentiful access to it. 

Remember, one reason why cartilage is slow to heal may be a collagen deficiency. 

There are a variety of collagen peptides benefits, not least that it’s incredibly practical and accessible. A liquid shot of collagen protein is a great way to start each day knowing that you’re loading your body up on the resources it needs to assist in wound recovery.

ProT Gold is medical grade collagen that is trusted by doctors across the country for its healing potential. The nano-hydrolyzed formula is easily digested, so it can swiftly be put to work wherever the body needs it the most. Try it for yourself and see how it may help you to reduce your recovery time.