This Supercrucifer is a cross between standard broccoli and a wild relative from Sicily.
The special ingredient is a compound called glucoraphanin, which our body turns into another, called sulforaphane, which appears to protect the joints.
The volunteers will eat 3.5 ounces of the super broccoli a day for two weeks before having surgery on their badly arthritic knees.
Lead researcher Dr. Rose Davidson and her team will then look at the tissue that has been removed to see what impact, if any, the broccoli has had.
Dr. Davidson doesn't expect to see any big changes after two weeks but hopes it will be enough time to offer some evidence that "super" broccoli could benefit humans.
Her team will simply be looking for proof that sulforaphane has traveled to where it is needed in the joint and that it is causing beneficial changes at the cellular level.
Another 20 knee replacement patients who have not been on the broccoli diet will be used as a control group.
Professor Alan Silman, of Arthritis Research UK, which is funding Dr. Davidson's work, told the BBC: "Until now research has failed to show that food or diet can play any part in reducing the progression of osteoarthritis, so if these findings can be replicated in humans, it would be quite a breakthrough."
The results of the animal trials were published in the journal Arthritis & Rheumatism (our favorite bedtime reading material).
The special broccoli, known as Beneforte, was developed from publicly funded research at the UK's Institute of Food Research and the John Innes Centre.
We would have called it Broccoman!
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