“I ruptured my anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament, lateral collateral ligament, patella tendon and had a chondral defect, which is a crater in the bone. Everything that held the top half of my leg to the bottom half just snapped in two and I was pretty much held together by the skin alone.”

Shaun Barker runs through the medical shopping list of injuries that destroyed his right knee three years ago in such a casual manner that it is easy to ignore the severity of what he is describing. You may assume he would struggle to walk again, let alone run, and certainly not play football – but here he is, after three years of gruelling rehab, with no hint of a limp, ready to resume his football career.

As with many career-threatening injuries, the circumstances were utterly innocuous. Barker was captaining Derby against local rivals Nottingham Forest in March 2012, when he collided with the goalkeeper Frankie Fielding while going for a routine near-post clearance. Fielding’s momentum ploughed through Barker’s leg, and just about everything that possibly could go wrong in a knee, did. The most striking thing about being in the stadium that night was that Barker lay completely still from the moment he hit the turf, and so innocuous was the incident that nobody seemed sure what happened, the assumption being that he had clashed heads with someone. Watching from the stands, Barker’s wife initially thought he’d suffered a heart attack.

“I felt a snap and heard a big crack, and felt my leg go the opposite way,” he says. “I knew I had a major injury and it was serious, so I thought the stiller I was and calmer I was, the better it would be … The physios came on and said my kneecap was sticking out and they had to put it back there and then. They put my whole leg back into place right there on the pitch.”

This was Barker’s second knee injury in a year (although the previous one, that had kept him out for seven months, had no bearing on this one) and the initial prognosis was for a year out with a dislocated kneecap, but once the swelling around his knee died down the full extent of the injury became clear and it was obvious that 12 months was ludicrously optimistic. The Derby physio Neil Sullivan said it “couldn’t have been much worse”.

“They’ve seen similar injuries, but it tends to be from rugby or American football, those sort of impact injuries,” Barker says. “It was the first time Andy Williams, who’s one of the top surgeons in the country, had seen it in football … So many people come up and tell me that they’ve done the same injury, and it’s really hard to tell them: ‘No, you really haven’t.’ A lot of footballers have done their ACL, and it’s a bad injury, but that’s nine months out. I did that, but I also did every other ligament in my joint.”

Others have attempted the ‘tough love’ approach. “People are really blunt. Friends feel like they can say anything to you. A couple of times people have said: ‘Let’s be honest, you’re never going to play football again.’” But talking to Barker, from the matter-of-fact, straightforward way he says that he will play first-team football again, you believe that is exactly what he will do. And if he doesn’t, it will not be for lack of determination.

Marcus Tudgay, right, calls for assistance after Barker’s injury. Photograph: Andrew Matthews/PA Archive/Press Association Ima

Barker had four operations, consulted and had rehab sessions with specialists in Germany and America as well as at home, and slowly, slowly, slowly built up strength in his knee over an excruciating period of time. “For the first two years I couldn’t walk to the shops without my knee flaring up and having swelling in it. I couldn’t stand up for more than 10 minutes. So many things that you take for granted, I realised I struggled with. I’d have to ice it after every single thing I did.” It took two years before he could even jog, another six months before he could train, and a further four before he could take part in a game, which he did for Derby under-21s in February.

For more than one reason Joe Simpson springs to mind, the climber and author of Touching The Void who suffered a similarly devastating knee injury at the top of Siula Grande in Peru and had to crawl, inch by inch, back to the foot of the mountain. Although Barker’s life was obviously never in threat as Simpson’s was, the mental side of both situations seems as tough – if not tougher – than the physical; the scale of both tasks almost unimaginable.

“Your brain remembers such trauma that you’ve got to tell yourself that it’s getting better,” Barker says. “You’ve got reinforce the fact there’s nothing wrong in your knee any more, and it’s just your brain protecting you because of what happened before. I need to teach my brain to do all these normal functions again. I’ve really enjoyed the process of learning how I’m getting better.”

Barker’s positive nature was a big factor in being able to mentally process his recovery, and his level head and an upbeat nature are consistent themes when his team-mates talk about him. “I’m a really positive person and really happy,” he says. “I want to do everything in life. I want to rule the world if I can! I think a lot of players struggle with the emotional turmoil of football, but I’ve been fairly consistent … Even though I should be really miserable I won’t allow myself to be, because I’ve got to keep the positivity to get myself fit again.”

The other problem with a recovery of this length is boredom. The grind of repetition that comes with rehab could be tricky to deal with, but Barker has kept himself busy, to say the least. “When I did the injury I knew there was a realistic possibility I wasn’t going to play again. I expected the best but prepared for the worst, and with that I looked at what would make me happy once I’d finished football and what would keep me entertained for the last three years.”

He started by blogging his recovery, complete with videos of various exercises; he is involved in a couple of fashion brands (SONS and With The Gods – the latter designs T-shirts that are sold in club shops); and this year set up his own charity. The Shaun Barker Foundation is designed to offer help in three areas around Derby: arts and culture, sports in the community, and social care, the latter being particularly close to his heart as his parents fostered around 180 children before retiring.

Music is a big thing too, as he frequently expresses his exasperation at the “soulless” sounds that generally come from the speakers in the dressing room, preferring the likes of Mogwai, Nick Cave and the Cure. He has music days and gigs of various sorts planned, working with the Quad, a cinema and arts space in Derby where we meet. During the interview, the centre’s chief executive wanders over to say hello, as does the leader of a local orchestra. It is clear he is a familiar face in these circles; not, perhaps, the direction into which many footballers might channel their time.

The x-ray of Barker’s knee, as taken from his phone. Photograph: David Sillitoe/Guardian

This suspicious interest in slightly more diverse music and culture led to his iPod being purloined and taped up by his Derby team-mates, and a fake Twitter account called “I am the worst iPod ever” set up. Banter, it seems, is alive and well. “I’ve been in football for 16 years and I’ve never had a conversation with someone about how great Explosions In The Sky are, or how great Leonard Cohen is. I’m unrelatable with stuff like that.”

Even with these added distractions, he is determined to make it back to first-team football. He played in six under-21 games at the end of the season (two at Sheffield United where Nigel Clough, the Derby manager at the time of his injury, took a keen interest) and started to feel and look close to his best, which makes Derby’s decision to let him go at the end of the season seem a little surprising. It appeared that he was part of the furniture at the club, despite not being part of the first team, and Derby even extended his contract by a year while he was out, so in some respects releasing him just as he was getting back to fitness seemed strange.

“I think they were almost resigned to the fact that I wasn’t going to play for them again, and my relevance to the club after Nigel left deteriorated,” he says. “I can accept that … I can understand from their point of view that if they don’t think I’m good enough then of course they’ve got to release me. There’s no sentiment there. I don’t take anything personally … There’s been tough times in that last 18 months in terms of personal stuff with the club, but I’ve always conducted myself in the right way.”

The phrase “first-team football” is repeated throughout the conversation, a goal that he says he will not give up on because it would be disrespectful to those who have helped his recovery. “I’ve worked too hard to not enjoy the remainder of my career, wherever it may be.”

Barker accepts that, at 32 and having been out of the game for three years, it will be tough to find anyone to take a risk on him (although his agent is speaking to clubs), but if any type of player was going to come back from such an injury, it would be Barker. If he was a nippy striker then you would not be so optimistic, but he was never especially quick anyway and relied more on positional sense, a tough challenge and ability in the air. Should someone take him on trial this summer, he is confident that he would impress them sufficiently.

“I’m not worried at all,” he says. “I’ve never worried about not being in the game. Some players become managers or coaches, but it’s not something I’ve been particularly bothered about. I’m looking forward to moving away from the football life, and get into the other things I’ve set up. But I’m just not ready yet.”