Better Joint Preservation with Modified Autologous Chondrocyte Implantation

Published in Orthopaedic Surgery - Winter 2017

Advancements in joint preservation can make it a viable alternative to arthroplasty for many patients, offering long-term solutions for younger adults and high-demand athletes. Bashir Zikria, director of the Johns Hopkins Sports Medicine Arthroscopy Lab, views the restoration of articular cartilage as the keystone of joint preservation.

“Before you do any procedure on the cartilage in the knee, you have to make sure the alignment is correct, the knee is stable and the protective mechanisms are in place,” Zikria says. After observing surgeons in Europe and the Middle East performing osteotomies, Zikria began incorporating that procedure into his practice, along with autologous chondrocyte implantation (ACI), osteochondral autografts and allografts, complex ligament surgeries, and meniscal transplantation, treating the knee holistically to better protect the cartilage.

“A knee joint’s final endpoint is often a replacement,” says Zikria. “You need to do everything you can before you get to that point.” He finds that ACI is an excellent option for young adults whose knees are often properly aligned. For patients who are 30 to 40 years old, an alignment procedure and meniscal transplantation may be needed, in addition to the ACI.

Zikria’s interest in innovative approaches to joint preservation developed from his own clinical experience. After surgically repairing his patients’ knees, he began finding that five years later, a certain population of patients developed arthritis. “I thought, I’ve got to do something better than this,” he says. “So I started thinking about better ways to preserve the cartilage.”

A typical ACI procedure involves MRI or CT arthrography to assess the lesion, and then two surgeries. First, surgery is performed to harvest normal articular cartilage, which is cultured in the laboratory. Eight weeks later, a second surgery involves placing a biomembrane patch over the lesion and injecting chondrocytes beneath it. At a cost of approximately $40,000, it is an expensive treatment.

Through his collaboration with radiologist Shadpour Demehri, Zikria is studying whether cells harvested through a small-punch biopsy of articular cartilage during CT arthrography will multiply adequately in vitro to allow enough volume for reimplantation into the affected area of the joint.

The first to try this modified ACI technique, Zikria and Demehri have successfully treated nine patients, reducing the treatment from two surgeries to one, shortening rehabilitative time and decreasing cost.

The two clinician-researchers are also in the process of creating a Biological Articular Cartilage Restoration Program at Johns Hopkins that they will co-direct. It will be a multidisciplinary, interventional program that will treat patients with joint degeneration using the latest evidence-backed techniques.

“The true breakthroughs come when you recognize the flaw in a technique and ask how we can do this better,” says Zikria. “We’re always working to improve.”