RENOWNED sports surgeon Professor Gordon Mackay can still remember the day he realised he wasn’t going to make it at Ibrox as a player. Graeme Souness and Walter Smith were taking training at which Mackay was rubbing shoulders with legends like Ally McCoist and Mel Sterland.

After training, Smith collared Mackay. “Doc, is it true that you’re actually a doctor?” he asked. “Er, yes it is,” said Mackay. “So are you any good at being a doctor?” said Smith. “I like to think so,” replied Mackay. “You might want to think about taking it up full-time then...” quipped Smith.

“I can take a hint,” laughs Mackay. “Besides, as well as lacking talent, I’d already had injury problems with my knees, so I took Walter’s advice. My time at Ibrox had shown me how many careers get devastated by ligament injuries, so I decided that investigating how we could treat those more effectively would be a good way to use my time. Which brings us to where we are today.”

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“Where we are today” is at the world’s foremost conference of sports surgeons – ESSKA, or the European Society of Sports Traumatology, Knee Surgery and Arthroscopy – which is being held in Glasgow for the first time. Proudly wearing his kilt, the 53-year-old Scot is a star attraction as he lectures to 4,000 delegates from around the world on his game-changing invention, the Internal Brace.

Ironically, given that Mackay hoped to forge a career at Ibrox, his invention of the Internal Brace – the biggest advance in sports medicine for decades – was partly inspired by Celtic defender John Kennedy’s traumatic career-ending injury in March 2004. That was one of the sporting tragedies which encouraged Mackay – then the surgeon for Rangers, Celtic and the Scottish Rugby Union – to invent a technique which heals major ligament injuries in half the time of a traditional surgery and without the later-life arthritis that accompanies traditional reconstructions.

The basic theory is to insert screws into the bone either side of the injury, across which is stretched a polymer lattice, which works like a tiny bungee cord. The damaged ligament can then grow back through the polymer.

“I was working with Celtic when John Kennedy suffered a horrific injury on his Scotland debut when Romania’s Ionel Ganea went through the back of John and severed all his knee ligaments,” remembers Mackay. “He was out for three years and never really recovered. He had five operations but was eventually forced to retire at 26 because the technology wasn’t there to save his career. Now it is.”

Mackay’s invention was used by German specialist Professor Karl-Heinz Frosch to rebuild European kitesurf champion Mario Rodwald’s knee after he sustained an injury even worse than Kennedy’s when he ruptured all his knee ligaments and was told he might never walk again. Instead, thanks to the Internal Brace, he was competing six months later. The technique is now widespread in the NFL, NBA and MLB, as well as among top skiers and Olympians. The Brazil football team’s medical team insist on it for all ligament injuries.

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Mackay’s work with the Scottish Institute of Sport, plus being the surgeon for Glasgow’s Commonwealth Games and Gleneagles’ Ryder Cup, has helped him extend many elite sportsmen and won’s careers. After Mackay repaired British bobsleigh pilot John Jackson’s ruptured Achilles tendon in half the time of a traditional reconstruction, allowing him to compete at the Winter Olympics, Dr Rod Jaques of the English Institute of Sport said: “I’ve been working in the field for 23 years and have never seen improvements like this. I’m astounded – the milestones he’s hit so rapidly are phenomenal.”

Ibrox’s loss has clearly been sports medicine’s gain.