From the lab, the first cartilage-mimicking gel that’s strong enough for knees

The thin, slippery layer of cartilage between the bones in the knee is magical stuff: strong enough to withstand a person’s weight, but soft and supple enough to cushion the joint against impact, over decades of repeat use. That combination of soft-yet-strong has been hard to reproduce in the lab. But now, researchers say they’ve created an experimental gel that’s the first to match the strength and durability of the real thing.