Surgeons Use Nose Cartilage To Repair Damaged Knee Joints

Swiss surgeons are using nose cartilage to operate on knees in Switzerland, reports a new study. The first-in-human phase I study used autologous cartilage tissue derived from nasal chondrocytes.

Two years following reconstruction, the majority of recipients experienced improvements in pain, quality of life, and knee function. They also developed repair tissue that is similar in composition to native cartilage.

About 2 million people across Europe and the USA are diagnosed every year with damage to articular cartilage because of injuries or accidents. Articular cartilage is the tissue on the end of a bone that cushions the surface of the joint and is vital for painless movement.

Since this tissue does not have its own blood supply, it has limited capacity to repair itself once damaged, leading to degenerative joint conditions like osteoarthritis. Traditional methods to prevent or delay onset of cartilage degeneration following traumatic events like microfracture surgery don’t create the healthy cartilage needed to endure the forces of everyday movement.

Nose Cartilage Safe And Feasible

Even novel medical advances using patients’ own articular cartilage cells have been unable to predictably restore cartilage structure and function in the long term. As the population ages and people live longer, there is an urgent and growing need to develop an effective therapy to repair cartilage damage.

The new treatment is safe and feasible, study co-author, Dr. Ivan Martin said, speaking to CNN.

“Moreover, results indicate that the tissue being formed at the patients’ repair site improves in composition over time, getting more and more similar to healthy cartilage,” added Martin.

The effectiveness of the procedure will need to be rigorously assessed in larger randomised trials compared to conventional treatments and with longer follow up before any firm conclusions can be drawn about its use in routine clinical practice, caution the authors.

The research team, from the University Hospital Basel, studied an alternative approach using engineered cartilage tissue grown from patients’ own cartilage cells from the nasal septum which have a unique capacity to grow and form new cartilage tissue.

The study took the concept to human subjects. 10 patients with full-thickness cartilage lesions of the knee were involved. The researchers extracted a small biopsy specimen (6mm in diameter) from the nasal septum under local anaesthetic using a minimally invasive procedure.

The harvested cells were multiplied by exposing them to growth factors for 2 weeks. The expanded cells were then seeded onto collagen membranes and cultured for 2 additional weeks, generating a 30 x 40mm cartilage graft.

The engineered graft was then cut into the right shape and used to replace damaged cartilage that was surgically removed from the recipient’s knee.

Substantial Improvements

Despite variable degrees of defect filling, MRI scans at 2 years revealed the development of new tissue with similar compositional properties of native cartilage.

Moreover, nine recipients (one was excluded because of several independent sports injuries) reported substantial improvements in the use of their knee and in the amount of pain compared to before surgery. No adverse reactions were reported, although two serious adverse events unrelated to the procedure were recorded; an independent injury in the opposite knee and new cartilage lesions at other locations in the treated knee.

Lead author Ivan Martin, Professor of tissue engineering at the University of Basel and University Hospital Basel in Switzerland, said:

“Our findings confirm the safety and feasibility of cartilage grafts engineered from nasal cells to repair damaged knee cartilage. But use of this procedure in everyday clinical practice is still a long way off as it requires rigorous assessment of efficacy in larger groups of patients and the development of manufacturing strategies to ensure cost effectiveness.

Moreover, in order to extend the potential use of this technique to older people or those with degenerative cartilage pathologies like osteoarthritis, a lot more fundamental and pre-clinical research work needs to be done.”

Dr. Nicole Rotter of Germany’s Ulm University Medical Center and Dr. Rolf Brenner of University of Ulm, writing in a commentary published with the study, said that long-term results

“will be needed to establish whether this technology has the potential to be approved by the European Medicines Agency and the US Food and Drug Administration.”

Marcus Mumme et al
Nasal chondrocyte-based engineered autologous cartilage tissue for repair of articular cartilage defects: an observational first-in-human trial The Lancet (2016). DOI: 10.1016/S0140-6736(16)31658-0

Image: Mike Baird/Flickr