Midfielder Jason Kennedy has been taking tests in London this week as Carlisle United continue work to get to the bottom of his injury nightmare.

The former Rochdale and Bradford man, 31, has been struggling with a persistent lower back problem for the majority of this season.

Fellow midfielders Kelvin Etuhu and John O'Sullivan are Keith Curle's other two main long-term injury concerns.

Asked for an update on the fitness of the trio, the Blues boss said: "They're all responding very well to their rehabilitation programme, apart from Jason.

"He's down in London to have some tests. [Physio] Neil Dalton went down to London on Thursday to get some more information and to get a better understanding of what tests and what procedures Jason is undertaking.

"He's got a full week [in London]. He's getting the attention from the daily testings to find out what the problems are."

"I think you would be better off talking to Dolly [Dalton] about the exact problem," Curle added. "But Jason hasn't been able to get the mobility that he needs, and he's having discomfort, stresses and strains around the pelvic area.

"They need to be diagnosed exactly as they're what is stopping him from moving so freely.

"He can perform in games for 20-25 minutes, then you have to shut him down for two days for everything to settle down.

"We haven't been able to build the intensity levels up because, the more we do with him, the more rest he needs. There's obviously an issue there that needs to get sorted.

"I think I'm right in saying we have tried different procedures, ranging from acupuncture to injections to operations to remove the stresses and strains.

"From my point of view, he can't run around in the way he needs to run around."