But McCaw has allayed any fears about his fitness, and will pack down as planned at Jade Stadium alongside back-row colleagues Jerry Collins and Rodney So'oialo.
"Richie is fine. He has progressed all week, and he is in great nick," said Henry. "He was always going to be okay."
Canterbury ace McCaw, who has won 27 caps and skippered the All Blacks against Wales last year, is rated a major threat to the Lions' Test series hopes.
Teams for New Zealand versus British & Irish Lions, first Test, Jade Stadium, Christchurch, Saturday, 0810 (BST):
New Zealand: L MacDonald (Canterbury); D Howlett (Auckland), T Umaga (Wellington, capt), A Mauger (Canterbury), S Sivivatu (Waikato); D Carter (Canterbury), J Marshall (Canterbury); T Woodcock (Auckland), K Mealamu (Auckland), C Hayman (Auckland), C Jack (Canterbury), A Williams (Auckland), J Collins (Wellington), R McCaw (Canterbury), R So'oialo (Wellington).
Replacements: D Witcombe (Auckland), G Somerville (Canterbury), J Gibbes (Waikato), S Lauaki (Waikato), B Kelleher (Waikato), R Gear (Canterbury), M Muliaina (Auckland).
Lions: J Robinson (Sale Sharks and England); J Lewsey (Wasps and England), B O'Driscoll (Leinster and Ireland, capt), J Wilkinson (Newcastle and England), G Thomas (Toulouse and Wales); S Jones (Clermont Auvergne and Wales), D Peel (Llanelli Scarlets and Wales); G Jenkins (Cardiff Blues and Wales), S Byrne (Leinster and Ireland), J White (Leicester and England), P O'Connell (Munster and Ireland), B Kay (Leicester and England), R Hill (Saracens and England), N Back (Leicester and England), M Corry (Leicester and England).
Replacements: S Thompson (Northampton and England), G Rowntree (Leicester and England), D Grewcock (Bath and England), R Jones (Neath-Swansea Ospreys and Wales), M Dawson (Wasps and England), W Greenwood (Harlequins and England), S Horgan (Leinster and Ireland).