A leading arthroscopic hip surgeon says former World No. 1 Andy Murray has reached "crunch point" in his battle to recover from a hip injury and added that surgery may be his only resort to save his career.

Murray pulled out of the Australian Open stating he was "not yet ready to compete" after failing to make a competitive appearance since his Wimbledon quarterfinal exit last July. In that loss to Sam Querrey, Murray struggled with his hip, limping and grimacing throughout the match.

"If you were to ask me what is going on with Murray, I'd say he's most probably got a labral tear and articular cartilage damage," Paul Jairaj, an arthroscopic surgeon at London Bridge Hospital told ESPN. "Why? Because 90 percent of the time that is the condition that stops athletes from competing. Could there be anything else, six months down the line? Unlikely."

"The whole tournament I've been a little bit sore," said Murray after the defeat to Querrey and having rested, his hopes of returning at the US Open at the end of August failed and he withdrew two days before it began. Season over. With his plans of a return in January now also ended, there's a growing likelihood of surgery.

"He's tried to get back on court through conservative means and the bottom line is he has been unable to know six months later," said Jairaj.

"If I had seen and examined him six months ago, was looking at his scans and assuming he has evidence of the injuries I mentioned, I would have treated him conservatively.

"This impingement usually occurs due to extra bone that is just below the ball [cam], or less commonly extra bone that forms around the socket (pincer) as well a lack of pelvic control which may come on after a period of time due to fatigue.

"I would say conservative treatment first most probably with a steroid injection and a physiotherapy programme, aiming to get back to competitive play after three months or so, and then we draw a line and reconsider our position. However if the damage is severe then surgery may be his only resort."

In his 12 years of hip arthroscopic surgery experience, Jairaj hasn't seen anyone with severe damage who can get back to major sport without surgery. The fact that other tennis players have never gotten back to the same level after surgery, he suggests is the reason why Murray's team are holding back.

Lleyton Hewitt never returned to the height of his power after undergoing hip surgery. Getty Images

That tale of caution comes in the form of another former World No. 1 Lleyton Hewitt, who had arthroscopic hip surgeries in 2008 and 2010 after labral tears, a surgery which Jairaj specialises in and one which Murray may need. Hewitt never got back to the heights he had hit previously and enjoyed only limited success thereafter.

Jairaj has dealt with elite athletes and does over 100 arthroscopic surgeries a year, recently performing a FAI / labral tear surgery on an athlete who had recovered and managed not only to recover within six months, but also competed at a global tournament.

Drawing on his own experience of dealing with hip injuries Jairaj stated that in rehab they would look to build greater strength to achieve better pelvic control which reduces the impingement, but this is only possible if the damage to the joint is minimal (inflammation or a very small tear).

Jairaj said: "The problem is when a tennis player returns to the court and gets themselves into hip-flexing and rotating positions, the irritation and inflammation -- which the steroids mask initially -- can then return because the labral tear and articular cartilage has no ability to heal by itself. What is also interesting is that the patient will find ways of compensating by putting stresses elsewhere; the back or other hip for example."

If Murray proceeds with the surgery he is contemplating, he needs to take a number of key issues into account according to Jairaj.

"If he's got labral tear and cartilage damage, this is crunch point for him now in his career. The aspects that will determine his outcome and the questions he should be asking are:

the size of the labral tear and its condition as this determines the seal that it forms around the ball the size of the articular cartilage damage he's got. That for me is the key prognostic factor, and how his capsule and iliofemoral ligament (one of the biggest ligaments in the body) are going to be managed [in surgery] as cutting these structures has the potential to cause scarring. Most, not all surgeons cut this structure and could be an additional factor as to why many athletes have not returned to the same level of play."

Arthroscopic hip surgeon Paul Jairaj says sometimes the actual damage is not known until a camera is put into the joint. Education Images/UIG via Getty Images

Interestingly, Jairaj adds that despite the latest imaging technology, the actual damage is not known until a camera is put into the joint. He recalls that there have been some "very significant surprises" from viewing a scan to then seeing it through the camera.

Outside of Murray's team, few if any, will know what is going on inside his hip, but whether or not he has articular damage or not, he will be told the same thing.

"There is a five percent chance this surgery won't work and ultimately in years to come you may need a joint replacement -- that is what will be quoted at Murray," he adds.

The failed comeback after months of rehab for Murray seems to indicate serious damage has been done. While there might be hesitation to have the surgery, Jairaj states that the athletes that have had surgery, have returned to their sport.

"The reason why there is such a reluctance to go down the route of surgery is potential outcomes in hip arthroscopic surgery -- one of the hardest surgery you can do orthopedically. The bottom line is if you look at the guys who have gone through this surgery, I don't think any of them have got back to the same level and that will be why he is saying it is a last option.

"Best case scenario, is that he has the surgery and makes a full recovery after six to nine, or even 12 months. Worst case? He's got massive articular cartilage loss, the repair doesn't take and he doesn't return to competitive play."

Jairaj added: "The elite athletes that I have had, even those with significant damage, we've got them back to do their sport again. I haven't had anyone that hasn't got back."