Calcium helps with bone repair, but they'll tell him what he ought to be doing.
He can expect a pretty long convalescence in any case. A riding buddy of mine, a physician, fell off his bike right in front of his hospital about three years ago and hit his hip on the curb, snapping the femur off right at the neck. It took him at least a year to get back near where he was, but he's done a couple of dozen centuries since, and plans to ride from Reno to Yosemite Nat'l Park (about 220 miles) in one shot in June, on the longest day of the year.