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Eye-Opening Treatment for Knee Arthritis

Study evaluates stem cell treatment used in eye surgery

Patient receives single injection of ReNu

By Deb Song

Orthopedic physicians at Rush are studying whether a remarkable treatment that’s been used in eye surgery for the past decade also can help alleviate osteoarthritis in the knees. Rush is the only medical center in Illinois and one of seven centers in the U.S. offering the new therapy.

The doctors are analyzing the effectiveness of a new form of biologic stem cell therapy that combines components of amniotic membrane tissue and amniotic fluid. Amniotic membrane is the inner layer of the placenta, and amniotic fluid is the fluid surrounding a fetus in the uterus. Both are a natural byproduct of childbirth, and the tissues and cells used in this treatment are harvested in the course of healthy, elective cesarean sections.

Amniotic fluid includes hyaluronic acid, which is commonly known as rooster comb or “gel injections” that are currently available. In addition to this, there is a cellular component that acts as an anti-inflammatory.

“Amniotic membrane has been shown to potentially increase tissue healing and decrease inflammation,” says Adam Yanke, MD, an orthopedic surgeon at Rush and the principal investigator of the study. “We also know from past studies that it is safe and that patients’ bodies do not reject the donor stem cells.”

“Shoulder and knee osteoarthritis is one of the most common reasons patients see an orthopedic surgeon,” says Brian Cole, MD, an orthopedic surgeon at Rush and co-investigator of the study. “Because of the risk of post-surgical pain and complications involved, finding a treatment alternative to surgery is a high priority for us.”

The most common form of arthritis, osteoarthritis is a currently incurable disease marked by deterioration in the tissues and bone of the joints, which causes pain and stiffness.

Osteoarthritis of the knee affects 10 percent of women and 13 percent of men age 60 or older. It is particularly common in individuals who play intense physical sports, such as football, and knee injury is a strong indicator for future development of osteoarthritis.

The study will compare the safety and effectiveness of a single injection with the stem cell treatment, called ReNu, compared to a treatment currently in use, hyaluronic acid, or a placebo injection. Patients with mild to moderate joint space narrowing in the knee may be included. However, patients that have been told they have “bone on bone” arthritis are likely not candidates.

The injection will be administered during a regular clinic visit. After treatment, patients will be followed up to 12 months to evaluate improvements using common pain and function subscales.

After the study is fully enrolled, Yanke, Cole and colleagues at Rush will offer the treatment option for patients who will be followed in a database monitoring outcomes of amniotic injections as part of routine treatment of osteoarthritis. These efforts will be used to prove the efficacy of this treatment option.

“This treatment is an exciting example of a biological therapy,” Yanke says. (Biologic therapies include the use of engineered tissue and cells to treat medical problems.) “Medicine in general and orthopedic treatments in particular are heading in this direction, and I’m glad that we can contribute to this progress by participating in this study. We are honored that we can be part of studies that will shape the future treatments we have to offer patients.”

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