Caption:HOUSTON, TX - DECEMBER 01: Former U.S. President George H.W. Bush waves during the game between the New England Patriots and the Houston Texans at Reliant Stadium on December 1, 2013 in Houston, Texas. (Photo by Bob Levey/Getty Images)
Dr. Sanjay Gupta on President GW Bush's neck fracture
04:18 - Source: CNN
CNN  — 

George H.W. Bush appears to be doing well after his hospitalization at Maine Medical Center earlier this month.

The 91-year-old former president tweeted Thursday, “Who knew jumping out of planes was safer than getting out of bed? Thanks to all for your kind get-well messages.”

RELATED: Former President George H.W. Bush released from the hospital

Bush spent his 90th birthday on June 12, 2014, jumping out of a helicopter near his summer home in Kennebunkport, Maine.

He was hospitalized July 15 after breaking his C2 vertebrae while at his Maine summer home. He was never disoriented and the injury did not result in any neurological problems, his spokesman, Jim McGrath, said after the incident.

Former U.S. President George H.W. Bush and Mike Elliott, US Army Sergeant 1st Class (ret), land on the lawn at St. Anne's Episcopal Church after jumping out of a helicopter on June 12, 2014 in Kennebunkport, Maine.

William D’Angelo, a neurosurgeon who was treating Bush, estimated that it would generally take someone of his age about three to four months to recover from the injury.

Two days after the incident, presidential candidate Jeb Bush said he knew his father would be OK.

“Dad gets in hospital fairly often,” the former Florida governor said at a town hall event in Carson City, Nevada, on July 17. “But when he starts telling semi-dirty jokes to the nurses, we know he’s on the rebound.”

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