The Blues [currently have 11 first team players either sidelined or at various stages of rehabilitation](https://www.eadt.co.uk/sport/24987020.ipswich-town-injuries-latest-ahead-crystal-palace-trip/) in Aro Murc (shoulder), Christian Walton (groin), Cameron Burgess (calf), Axel Tuanzebe (hamstring), Kalvin Phillips (calf), Wes Burns (knee), Chiedozie Ogbene (knee), Julio Enciso (knee), Omari Hutchinson (knee), Samie Szmodics (ankle) and Conor Chaplin (knee).
Indeed, the majority of players in Town's squad have missed matches through injury at some stage this season, with Cieran Slicker (hand), Ben Johnson (thigh), Jacob Greaves (hamstring), Sam Morsy (abdominal), Jens Cajuste (knee), Jack Taylor (thigh), Massimo Luongo (ankle), Nathan Broadhead (hamstring) and George Hirst (knee) having all previously been in the treatment room.
"There's never one reason," said McKenna, when quizzed on the issue.
"There's always going to be a multitude of them and not all of them we'll reflect upon or share publicly. But of course we'll do that internally.
"There are a lot of different factors. Always in football you have a run of injuries and luck plays a part in that.
"We've had one, stroke two of those runs in the last two-and-a-half years. I remember in my first full season, in League One, we had a period in the autumn time where we had seven, eight, nine, 10 injuries and we didn't work any differently to the six months previous or the two years after that.
"Wes Burns and Chieo Ogbene, cruciate and Achilles, are injuries that no-one's got a crystal ball for. If anyone did have a crystal ball for those then they wouldn't happen because they're the most serious injuries in football.
"Sam Szmodics - a tackle. Omari Hutchinson - a tackle. Conor Chaplin - innocuous injury in his knee from blocking a shot. Axel has an unlucky one (freak domestic accident injuring thumb). We've had quite a lot of unlucky injuries like that.
"We haven't had a very high proportion of muscle injuries, to be honest. They're the ones that you always reflect on a little bit more and think if there's anything that can be adapted.
"We've, of course, adapted the training schedule as the season's gone on, as we always do, to work at an appropriate level.
"I also think the reality is we're competing in the most physical league in the world, we've got very few players who have competed at this level ever, or for a lot of games in recent times, and if you come into a season with that as the make-up of your group, and the group works very hard and competes every weeks as they do, then you're probably going to pick up more injuries than you have playing at levels players have competed at previously.
"Of course it's made it more of a challenge. We'll reflect on things that we can change and can improve, which I'm sure there are a few, but there are also a lot of factors that we're not in control of.
"It's about making the best of the situation which many times this season the group has done. We're going to have to do it again between now and the end of the season as well."
Town, five points adrift of safety in the Premier League relegation zone, head to Crystal Palace on Saturday. There are 11 games to play.