United players have a curfew restricting their activities on the two days before a game, so Ronaldo was not there to collect the trophy ahead of tomorrow's crucial Champions League semi-final against Barcelona at Old Trafford. He was shown on screen accepting his award from manager Sir Alex Ferguson at the club's training ground.
"It's one of the biggest games of the whole season on Tuesday and no one could have expected him to be able to come," said PFA chief executive Gordon Taylor.
"Cristiano and Sir Alex have been as good as gold and we appreciate their help."
Arsenal's Henry collected the award in 2003 and 2004, and Ronaldo, with 41 goals for club and country so far this term, becomes only the second player to have won it two years in succession.
Ronaldo, who also won last year’s PFA Young Player of the Year award, paid tribute to his team-mates, and said that to be honoured again was an encouragement to work harder.
"I feel very happy,” he said. “When you work all season to play good, to do something for the team, to do your contribution for the team and then at the end of the season the PFA give you this award, it is a great moment, it is an honour, a pleasure.
"It is a great motivation to carry on like that, to work more and get better.
"I feel very good but it is not just my award, my team-mates have helped me a lot this season. They give me good passes to score goals - and I score - but it is a good moment for me.
"I am sure I am better player than four or five years ago. Than last year? I have improved a little bit better still.
"This is my ambition to learn more and play better and I think I am in the right place. I want to carry on and this for me is a good moment to stay at the club and play at the best level."
Cesc Fabregas may have lost out to Ronaldo for the main award, but he beat the Portuguese to the consolation prize, the PFA Young Player of the Year. He also pipped fellow countryman Fernando Torres, Micah Richards, Gabriel Agbonlahor and Ashley Young.
Fabregas is the Premiership’s leading assist maker with 18, and has himself scored 13 in all competitions.
"I'm very proud. It's a very prestigious trophy," he said on receiving the junior prize. "Football is a collective game and you prefer to win trophies with team-mates but it's always nice to have this type of award."
Fabregas is the first Arsenal player to be awarded the junior prize since Nicolas Anelka was named Young Player of the Year in 1999.