What Causes Knee Pain?

Richard Cunningham, MD is an expert knee surgeon who offers innovative treatments for patients with knee pain. There are several common causes of knee pain including:

  • Knee arthritis: Knee osteoarthritis, or wear and tear arthritis, causes pain and swelling
  • Tendonitis: Tendons surrounding the knee are prone to painful inflammation.
  • Ligament Tears: These painful injuries are often due to sudden deceleration or twisting and pivoting on the knee causing a ligament to tear.
  • Meniscus Tears: the meniscus is the rubbery shock absorber cartilage between the bones that helps to protect the articular cartilage.
  • Articular Cartilage Damage: Articular cartilage is the coating cartilage on the ends of our bones in our knee joints, allowing smooth gliding between the ends of the bones. It can be damaged from an acute injury or due to wear and tear resulting in knee arthritis.

What is Articular Cartilage Damage in the Knee?

Articular cartilage damage of the knee is very common. This type of cartilage injury is found in over 60% of knee pain patients. Articular cartilage damage is graded on a 1-4 scale. The grading scale is:

  • Grade 1 – cartilage displays areas of softening
  • Grade 2 – thinning of the cartilage, but not down to the underlying bone
  • Grade 3 – Cracking and fraying of the cartilage down to bone
  • Grade 4 – Complete loss of cartilage exposed areas of bone

Knee doctor Richard Cunningham, MD can evaluate a patient with knee pain and provide an accurate diagnosis of articular cartilage damage. With a complete evaluation and diagnosis, Dr. Cunningham can provide a treatment plan for patients with knee pain caused by articular cartilage damage.

How to Regrow Cartilage in the Knee

On its own, cartilage of the knee cannot regenerate. However, Richard Cunningham, MD employs a number of different specialized techniques to treat and even restore articular cartilage to areas where cartilage has been damaged or lost. These procedures include:

  • Chondroplasty – as articular cartilage wears, the surface become very rough. A chondroplasty is done arthroscopically and in this procedure, the rough cartilage is smoothed and any torn cartilage edges removed.
  • Microfracture and Bone Marrow Stimulation – This technique has been around for many years and its current indications are limited. However, in some cartilage injuries, this technique is useful. For hard to reach and small areas of cartilage loss in the knee, the exposed bone is penetrated with a small pick or pin in order to fill the cartilage defect with bone marrow elements that then develop into a fibrocartilage patch. This patch is a mixture of cartilage, bone, and fibrous tissue and not pure cartilage. It is much like patching a pot hole in the road.
  • Osteochondral Allograft Implantation – In this technique, an area of worn cartilage and some of the underlying bone is removed as a core and then replaced with a core of normal cartilage and attached bone taken from a donor knee. The technique is much like changing the putting hole on a golf green where a core of cartilage and bone is implanted into an area where there is no cartilage.
  • Autologous Chondrocyte Implantation (ACI) – ACI is a two-part surgical treatment for areas of cartilage loss in a knee. In the first stage, an arthroscope in placed in a knee and a small biopsy of normal cartilage is taken from the affected knee. The sample is sent to a lab where the cartilage cells are isolated and then multiplied in culture. In stage two, the cartilage defect is prepared and the cartilage cells are implanted into the defect, where they grow and mature over time into a new cartilage layer. This innovative procedure is providing promising results to patients in regaining true articular cartilage in the knee.

Dr. Cunningham is a surgically trained specialist in the third generation ACI innovation known as Matrix-induced Autologous Chondrocyte Implantation (MACI). MACI is an even safer and less invasive iteration of the original ACI procedure developed over 20 years ago. Dr. Cunningham can evaluate patient eligibility for this MACI treatment which helps to restore articular cartilage and eliminate knee pain.

What is the MACI Knee Treatment?

A MACI knee treatment utilizes a patient’s own (autologous) articular cartilage cells, multiplies the cartilage cells in the lab, and implants the new cartilage cells onto a collagen membrane which is then implanted into an articular cartilage defect. The treatment is a two step process described here:

  1. After a comprehensive evaluation of the articular cartilage in the patient’s knee, utilizing diagnostic imaging, a first step arthroscopy is performed and a biopsy of a few pieces of healthy knee cartilage are removed. These cartilage fragments are taken from a non-load bearing section of the knee. The tissue is sent to the lab, and the patient waits one month for the cells to be grown and ready for reimplantation into the knee.
  2. In the lab, the cartilage cells are reproduced and physically expanded. Once ready, the expanded cells are placed onto Type II collagen matrix membrane and returned to Dr. Cunningham for the second step of the procedure.
  3. The patient is taken back for the second stage of surgery, and the membrane is fitted to the shape and size of the cartilage defect. It is then surgically implanted into one or more cartilage lesions in the knee.
  4. The treated cartilage cells separate from the membrane, join with cartilage proteins present on the native tissue, bond to the exposed bone and grow a new layer of cartilage where there once was no cartilage. This creates a strong viable repair tissue which matures into a new layer of cartilage.
  5. Rehabilitation begins with Dr. Cunningham’s prescribed progression of physical therapy. Patients find they are able to return to an active, pain free lifestyle.

ride the road to recovery

Dr. Cunningham utilizes innovative treatment techniques to get patient’s back on the road quicker.

What are the Benefits of MACI Knee Treatment?

Regrowing articular cartilage has been “the Holy Grail” of orthopedics and this cutting edge technique is bringing this goal into reality. The MACI technique is a viable treatment option for patients with isolated articular cartilage damage. It is not an option for those with generalized cartilage wear throughout their knee. Patients often experience long-lasting pain relief after a MACI procedure and can resume their active lifestyle, thus improving one’s quality of life.

If you are suffering from articular cartilage damage, contact knee doctor Richard Cunningham, MD to see if you are a candidate for MACI. Dr. Cunningham treats patients throughout Colorado including Vail, Frisco, Breckenridge, Denver, Colorado Springs, Aspen, and Grand Junction, CO.


Rediscover your inner athlete

Dr. Cunningham specializes in the treatment of knee, shoulder, and sports injuries.