* U.S. crude rises more than 6 percent
* Energy top gainer among S&P sectors
* Health insurers up; govt proposes hiking Medicare payments
* Indexes up: Dow 1.37 pct, S&P 1.28 pct, Nasdaq 1.36 pct (Updates to afternoon)
By Noel Randewich
Feb 22 (Reuters) - Wall Street surged on Monday, helped by a robust rally in oil prices that lifted recently-crushed energy stocks, including Chevron and Schlumberger.
As it has for months, Wall Street followed the lead of global oil prices in a trend that has left the S&P 500 down 5 percent so far in 2016, following a partial recovery last week.
Monday's stock gains were broad, with all 10 major S&P sectors higher, but investors shell-shocked by this year's market turbulence remained wary.
"I don't think we're through the mess," said Kurt Brunner, portfolio manager at Swarthmore Group in Philadelphia. "You still have concerns about China and where growth goes there, and that's why you're still going to have this volatility."
U.S. crude prices settled up more than 6 percent, while prices of industrial metals such as copper and zinc rose as investors worried about potential shortages.
At 2:33 p.m., the Dow Jones industrial average was up 1.37 percent at 16,616.04 points and the S&P 500 had gained 1.28 percent to 1,942.33. The Nasdaq Composite added 1.36 percent to 4,565.73.
The S&P energy sector rose 2.2 percent, boosted by Chevron's 3-percent increase. The materials sector rose 1.8 percent. Alcoa and Freeport-McMoRan were the biggest influences, both surging 12 percent.
Recent turmoil in global markets and macroeconomic uncertainty has left investors split over whether the U.S. Federal Reserve will raise interest rates this year.
Among S&P 500 companies, there have been 75 negative EPS pre-announcements for the first quarter, compared to 16 positive pre-announcements, according to Thomson Reuters I/B/E/S.
UnitedHealth, Anthem, Humana, Aetna and other insurers were up after the U.S. government proposed raising payments to health insurers who offer Medicare Advantage health benefits to elderly and disabled Americans.
UnitedHealth was up 3.06 percent, providing a major boost to the Dow.
Shares of Aerospace component suppliers Honeywell International Inc fell 1.8 percent and United Technologies Corp, a Dow component, rallied 5.7 percent after CNBC reported the two have held merger talks.
Advancing issues outnumbered decliners on the NYSE by 2,421 to 610. On the Nasdaq, 2,046 issues rose and 712 fell.
The S&P 500 index showed 18 new 52-week highs and one new low, while the Nasdaq recorded 35 new highs and 27 new lows. (Additional reporting by Abhiram Nandakumar in Bengaluru; Editing by Nick Zieminski)