• Posted March 11, 2025

Nose Cartilage Can Help Repair Knee Injuries, Researchers Say

An awkward fall while running, skiing or playing sports can cause knee injuries that sideline players and increase their risk of future arthritis.

But most of the time, there’s nothing wrong with their noses, and that might prove the key to repairing their knees and getting them back on their feet, a new study suggests.

Replacement cartilage engineered from the nasal septum -- the cartilage wall that separates the left and right airways in your nose -- can be used to repair even the most complex knee injuries, researchers report in the journal Science Translational Medicine.

“Nasal septum cartilage cells have particular characteristics that are ideally suited to cartilage regeneration,” senior researcher Ivan Martin said in a news release. He's head of biomedicine with the University of Basel in Switzerland.

For example, it has been shown that these cells can counteract inflammation in joints, researchers said.

Torn cartilage in the knee can create long-term problems for active people, because this tissue does not heal itself. Cartilage forms a buffer between bones, and a loss of cartilage will eventually lead to arthritis.

The new knee repair process involves extracting cells from a tiny piece of a patient’s nasal septum, and then growing the cells in a lab on a scaffold made of soft fibers, researchers explained in background notes.

The newly grown cartilage is then cut into the required shape and implanted into the knee joint.

For their new clinical trial, researchers recruited 98 patients at clinics in four different countries.

The trial compared two different approaches involving cartilage grafts grown for only two days prior to surgery versus grafts allowed to mature for two weeks.

Participants were tracked for two years, regularly reporting their well-being and how well their repaired knee was working.

Results showed clear improvements in both groups, but those who received the more mature grafts fared better, researchers said. 

They continued to improve even in the second year following the procedure, overtaking the group with grafts grown in a couple of days.

MRI scans showed that the more mature cartilage grafts resulted in better tissue composition at the site of the implant, even benefitting nearby natural cartilage.

“It is noteworthy that patients with larger injuries benefit from cartilage grafts with longer prior maturation periods,” investigator Andrea Barbero, a research group leader with the University of Basel, said in a news release.

This also applies to cases where previous cartilage treatments with other techniques have been unsuccessful, Barbero noted.

Researchers next plan to test this procedure’s effectiveness for treating wear-and-tear arthritis caused by the degeneration of knee cartilage.

The procedure could prove an alternative to knee replacement surgery if results pan out, researchers concluded.

More information

The Cleveland Clinic has more about torn cartilage in the knee.

SOURCE: University of Basel, news release, March 5, 2025