bone on bone

‘Bone on bone’ knee osteoarthritis

Knee cartilage starts to wear away as we get older. Symptoms of knee pain and swelling develop as the cushioning of the cartilage begins to fail. So what happens when you have no cartilage in knee, and what can you do about it? We discuss treatment options for ‘bone on bone’ knee cartilage damage in this blog.

Causes of no cartilage in knee

The most common cause of knee cartilage damage is osteoarthritis. Knee cartilage loss can be due to an injury to the knee, such as a ligament tear, patellar dislocation, or meniscal tear. In addition, loss of knee cartilage can be triggered by lifestyle factors such as weight gain, diabetes, and high cholesterol. Also, inflammatory arthritis conditions such as rheumatoid arthritis can lead to further knee cartilage damage. Overall, osteoarthritis of the knee is not as simple as ‘wear and tear’. Without proper diagnosis and treatment, osteoarthritis can quickly degenerate the joints even further until bone on bone knee damage is seen.

Symptoms of knee cartilage damage

Generally, symptoms of worsening loss of knee cartilage include pain with activity, swelling of the joint, and reduced knee joint function. Often, previously simple tasks such as walking, housework, and standing from sitting become more difficult due to pain, swelling, and restriction.


But all is not lost. A variety of treatments are used to treat cartilage loss in knee. Generally, treatments range from simple weight loss and exercise measures to more invasive treatments such as injections or surgery. Overall, we recommend simple treatments first for cartilage loss in knee.

Weight loss

In general, weight gain leads to worsening symptoms and progression of osteoarthritis. Firstly, increasing weight places more significant pressure on the knee joints leading to greater knee cartilage damage. It is well known that obese people develop osteoarthritis at an earlier age and have worse pain than healthy people. Secondly, increased fat cells in the body stimulate insulin production leading to chronic inflammation. This type of inflammation leads to more significant cartilage degradation and worsening cartilage loss in knee.

Overall, losing weight reduces pressure on the joints and reduces body inflammation improving symptoms. Studies suggest that a 10% reduction in weight leads to a 50% reduction in knee pain from cartilage loss – a vast improvement.

Exercise therapy 

Exercise in the form of strength training and aerobic conditioning improves symptoms from loss of cartilage in knee. Symptom improvement occurs from lowering chronic inflammation in the body combined with weight loss and improvement of muscle strength. In addition, strengthening the muscles around the knee helps offload the knee and reduce pressure on the joint. Studies suggest that a combination of gym, pilates, yoga, and Tai Chi is the most effective for improving pain and function.

Generally, exercise works the best for the following:

  • younger patients, although older patients still benefit.
  • Knee arthritis. There are over 50 high-level studies showing exercise works in knee arthritis.
  • An exercise program that follows the American College of Sports Medicine guidelines. So, a combination of aerobic, resistance training, and balance exercises with the progression of strength training. Generally, the stronger you get, the better. Also, a supervised program with a personal trainer works best.

Can I run with knee arthritis?

There are no simple answers. An exercise program aims to improve symptoms and general exercise tolerance, including running. We always say to people that running should be your goal if you enjoy it. However, some people might need to reduce their running depending on pain. If you have true ‘bone on bone’ knee cartilage damage, you should find a lower impact form of exercise.

The good news in this study: running at your own pace does not worsen cartilage loss in knee on X-ray and may improve your pain.


An offloading brace can be effective when cartilage loss in knee s confined to one area of the knee only. These offloading braces push the knee away from the side of no cartilage, reducing pressure and inflammation in that part of the knee. Generally, braces are OK at reducing pain and improving function in the knee. However, some people find them uncomfortable.

NSAIDs for cartilage loss in knee

Over-the-counter medications such as ibuprofen reduce pain associated with no cartilage. However, the effect is negligible. Your doctor will be able to prescribe more effective medication to alleviate pain associated with bone on bone cartilage damage. But, you need to be aware of possible side effects such as gastritis, reduced kidney function, and increased blood pressure. One alternative to tablets is topical NSAID creams or ointments, which have shown to be effective in relieving the pain of hand and knee osteoarthritis.

Cortisone injection for no cartilage in knee 

Cortisone is a powerful anti-inflammatory drug that reduces inflammation and pain.

In general, studies suggest short-term and mild improvement of knee pain for up to 8 weeks. However, recent studies show that cortisone is no different from placebo for knee arthritis at six months. Also, there is concern about repeated cortisone injections causing more knee cartilage damage. Overall, we use cortisone injections less for longstanding cartilage loss in the knee and reserve these injections only for a severely swollen knee.

Knee gel injection for cartilage loss in knee 

A gel injection, also known as viscosupplementation, is the injection of a naturally-occurring substance called hyaluronic acid into the knee joint.

How these gel injections work is unknown, but we think they lubricate the joint or control inflammation by natural means. Some examples of commonly used gel injections include Gel-One, or Synvisc 1. Previously, repeated injections every week were required. There is a high molecular weight, a longer-acting gel that only needs to be injected once. Overall, these injections can last 6-12 months.

Recent studies suggest that the high molecular weight non-animal product hyaluronic acid such as Durolane works best for arthritis of the knee and hip. Also, if the first injection works, repeat injections are likely to work up to about five repeat injections.

Gel injections work better if the knee is quiet with no knee fluid. So, your doctor may empty the knee joint with fluid before injecting the gel. This is one of the most effective and immediate treatments to alleviate pain associated with bone on bone knee cartilage damage.

PRP injection knee for bone on bone, no cartilage in knee

Platelet-rich plasma injections

Platelet-rich plasma, also known as PRP, is a concentrated source of platelets. We obtain PRP from your whole blood. Then, the blood is spun in a centrifuge, separating the plasma from the white and red cells. This plasma contains concentrated platelets, which have many growth factors. Overall, we believe that PRP works by allowing the growth factors to settle chronic inflammatory cells leading to lower pain.

Recent studies suggest that PRP or platelet-rich plasma improves knee pain from the loss of cartilage in knee for over 12 months compared to gel injections, cortisone, and other substances.

Currently, 23 randomised trials show that PRP is better for no cartilage knee than other injections such as cortisone and hyaluronic acid. Also, we think that a type of PRP called leucocyte-poor PRP (compared to leucocyte-rich) has a good effect with less risk of a flare.

Often, 2-3 injections are needed about two weeks apart.

Combining PRP with hyaluronic acid 

Recent evidence suggests that combining PRP with hyaluronic acid in the loss of cartilage in knee might be better than PRP alone. This positive effect is seen at 3, 6, and 12 months. Also, we think that adding hyaluronic acid reduces the risk of a flare after a PRP injection.

When combining treatment for knee cartilage damage, we recommend one high molecular weight hyaluronic acid and 2 PRP injections.

Surgery for ‘bone on bone’ cartilage loss in knee: what are the options? 

Surgical options for bone on bone cartilage loss in knee are limited.

Firstly, keyhole surgery for knee cartilage loss is ineffective and could accelerate knee damage.

High tibial knee osteotomy can reduce pressure on the knee joint if there is a malalignment problem. However, evidence for effectiveness is not strong, and risks are real.

Finally, knee replacement surgery effectively reduces pain and improves function compared to physical therapy. Still, the sting in the tail is that 16% of people have problems after this surgery – some of these are serious. The bottom line is that surgery should only be done once your pain and activity levels become unacceptable.

Knee cartilage repair without surgery: Is it possible? 

So overall, there is no current non-surgical treatment that will repair or regenerate cartilage in the knee. Even surgery for cartilage replacement is problematic. Injections such as PRP, hyaluronic acid, and stem cells have not demonstrated cartilage regeneration in arthritis. Procedures injecting stem cells into knee joints have not shown better results than any other injection, including a placebo.

Other commonly asked questions about cartilage damage in knee:

Will my knee arthritis get worse? 

Not necessarily. The chances of having a knee replacement are only 30% in your lifetime. Generally, the best way to prevent the progression of knee cartilage damage is to keep a healthy lifestyle: exercise, lose weight and stop smoking. If you gain weight, your chances increase from 30% to 35%.

Does arthroscopic surgery help knee arthritis? 

No. Some studies suggest it may worsen cartilage loss in knee.

When to have knee surgery for arthritis? 

Generally, every person is different. But we suggest considering a knee replacement if you need to reduce your step count to 7000 or less per day due to pain. However, the good news is that most people (85%) get back to their chosen sport five months after a knee replacement. These activities include walking, skiing, and even running.

Final word from Dayton Orthopedic Surgery about no cartilage in knee

Loss of cartilage in the knee is expected as we get older. Weight loss and exercise are the best medicines to reduce pain and improve activity. Only use injections sparingly to help with lifestyle factors with a preference for knee gel and PRP. Avoid any expensive treatments like stem cells that promise regeneration. Finally, consider a knee replacement if all other treatments fail and your ability to exercise drops.