LAURA Macdonald was not aware of the damage being done at the time. The alto saxophonist was taking a workshop with the young musicians who attend the popular jazz classes at the Tolbooth in Stirling and she was so swept up in the sound and enthusiasm of the session that it was only when she got home that she felt the pain in her stomach.

At first she thought it was a simple stomach upset. So she took herself off to bed but over the next day or two it became clear that something was amiss. Taking deep breaths left her in agony and when she touched her side she found a lump.

“I thought I had a hernia because that’s apparently quite common among brass players,” she says. “In fact, the doctors thought that was the problem, too, at one point, but it turned out that I’d torn part of the muscle right at the top left-hand side of my ribcage and I was ordered to take a complete rest for ten weeks.”

Ten weeks’ inactivity stretched to three and a half months. This resulted in a lot of cancelled gigs, including a concert at Aberdeen Jazz Festival that she had to call off at three days’ notice, and put the instrumental teaching for South Lanarkshire Council, about which Macdonald is so passionate, on hold.

“Even taking my two children to school became a problem because I couldn’t get in and out of the car and I couldn’t walk very far without getting out of breath,” she says. “I obviously couldn’t play the saxophone, so the first couple of weeks were pretty depressing and when I tried to find other musicians who had suffered the same injury, it seemed that nobody had had the same experience.

"Then somebody put me in touch with another saxophonist, a London session player called Graham Blevins. Exactly the same thing had happened to him on the first day of a world tour with Kylie Minogue. He didn’t know what he’d done to cause the damage either, and that’s the weird thing: you don’t know what steps to take to avoid doing it again.”

Involuntary time off, apart from letting her catch up with a whole lot of boxed sets on Netflix, gave Macdonald space to take care of the admin that freelance musicians generally look for excuses to put off. It also gave her time to consider her own career as well as the careers of two of her close musical associates who have been doing rather well lately.

Saxophonist Donny McCaslin and drummer Antonio Sanchez were once members of Macdonald’s sextet in the years following her studies at Berklee School of Music, where they all met. The former’s profile rose dramatically when his group became David Bowie’s final collaborators on his Dark Star album and the latter’s career has shifted a few gears with his success as the composer of the soundtrack to the film Birdman.

“Antonio was already doing some amazing stuff when he was in my band. He was off touring with Pat Metheny even then, although obviously working with me will have worked wonders for his compositional talent,” says Macdonald with tongue in cheek. “Donny, though, really has gone through a spectacular train of events. It’s fantastic to see both of them doing so well. I’m not surprised because they’re both wonderful musicians. It just means that if we ever put that edition of my band together again it’ll cost a fortune to book us and that’s before we get into finding space in these guys’ diaries.”

On the concerts she’s played since getting the medical all-clear Macdonald has concentrated on the music she grew up with, the Great American Songbook, rather than presenting her own compositions. As a 16-year-old learning the saxophone she was drawn to these timeless classics by composers such as Jerome Kern, George Gershwin, Cole Porter and Harold Arlen and in her early gigs in cocktail bars and with the late pianist and great Glasgow jazz character Sandy Taylor those were the tunes she needed to know.

“I suppose I got into writing my own material quite late and it also takes quite a long time to find your own composer’s voice,” she says. “I realised that the Great American Songbook, standards, call them what you will, offer endless possibilities for reinvention. My dad was a jazz singer and those are the songs he sang and the songs that he and my mother listened to, and they must have seeped into my bones.

"Certainly when I was a teenager, going through books of these songs helped to make me fluent on the saxophone. That’s where I got my grounding and I love going back and exploring them. It doesn’t have to be about taking them somewhere new, you can just play them and they’ll inspire your own creativity.”

There’s another aspect – maybe an obvious one – about the Great American Songbook that appeals to her. They’re songs. With words. This is something that Macdonald continually reminds her students about. Some of the greatest ballad players in jazz – the Glasgow-born saxophonist with one of the most distinctive sounds in all of jazz, Bobby Wellins, was a prime example – have often chosen to play certain songs because of their lyrics as much as for their melodies.

“I think that’s why I’m drawn so much to Cole Porter’s True Love,” says Macdonald, who released an album of ballads, Duets, with American pianist David Berkman a few years ago. “It’s a beautiful tune but the lyrics are so emotional and if you keep them in mind as you play, they guide you through the melody, tell you how to approach the phrasing that will bring out the song’s meaning. That’s also true of upbeat songs, of course, not just sad or poignant ones, and that’s the thing I emphasise to my students because in the Real Book, the book of standards that musicians work from, the notes don’t tell you what emotions to use, so you have to learn the words, too. ”

As she gets back on the road, having worked her way back with gigs at Edinburgh and Islay jazz festivals, Macdonald is fronting a quartet that might not require the big bucks that putting her illustrious sextet with McCaslin and Sanchez back together would take but is responding to her leadership with inspiration and stimulating interaction. Guitarist Kevin Mackenzie, bassist Mario Caribe and drummer Stu Brown are all bandleaders in their own right and Macdonald is loving working with them.

“I don’t mind admitting that the choice of material we play is completely selfish,” she says. “We’re playing the tunes I love and the guys are completely up for that. Someone came up to us after the gig we played at Islay Jazz Festival and said, Wow, these are all old tunes but you made them come alive in the moment, and that’ll do me. It helps that we know we’re playing beautiful music. That’s a great starting point for spreading a feeling of happiness and satisfaction.”

The Laura Macdonald Quartet plays Jazz at St James in Leith on Saturday, October 20 and Jazz at the Merchants House of Glasgow on Sunday, October 21.