When Dr. Rachel Frank explains cartilage transplantation to her patients, she tells them the purpose is to improve their quality of life by reducing pain in the damaged area and improving function.

By that token, the surgery Avalanche captain Gabriel Landeskog underwent Wednesday is “incredibly successful in the vast majority of patients,” said Frank, an orthopedic surgeon and Colorado Rapids team physician who specializes in cartilage and joint restoration.

The $42 million question in the Avalanche’s case is whether Landeskog’s surgery can be effective with a more ambitious end goal.

“For an elite athlete or professional athlete, the definition of success is certainly going to include those things,” Frank said, “but also includes the ability to get back to playing that sport at that (elite) level.”

Landeskog is among the most elite competitors in his sport when healthy. But the Avs wing has been combating an injury to the cartilage in his right patella since 2020 when his knee was cut by a skate blade. After three prior procedures, most recently an arthroscopic surgery in October 2022, he resorted to a cartilage transplant Wednesday that will sideline him for at least the 2023-24 regular season.

The October surgery was supposed to precipitate a 12-week rehab process. Instead, Landeskog never felt comfortable intensifying his skating. He missed the full season.

“This is the (option) we feel is the best way forward and the best solution for me to come back and play hockey again,” Landeskog said Tuesday.

The Post spoke with three doctors with orthopedic expertise to understand what Landeskog’s surgery entails and what it might mean for his future on the ice. The leading consensus: A cartilage transplant is the best route forward after an athlete has exhausted other options, but the modernity of the procedure and lack of data suggesting effectiveness for athletes returning to heightened physical demand makes it difficult to determine the eventual impact on Landeskog’s game.

“The jury’s still out long-term in terms of professional athletes,” said Dr. Daniel Kharrazi, a Los Angeles-based orthopedist who used to work with the Lakers. “… The option is do you retire? Or do you do something to try and get back to how you were?”

“We’ve seen this done before in patients and athletes at all levels, including the high school, the collegiate and the professional athlete,” Frank said. She trained under Dr. Brian Cole, who performed Landeskog’s surgery in Chicago, according to the team’s news release. “But at the elite level, it’s a bit less predictable because, quite frankly, it’s not as common.”

Landeskog has found solace in one contemporary going through the same process. Chicago Bulls guard Lonzo Ball underwent a left knee cartilage transplant in March. Landeskog contacted Ball while researching the surgery, Landeskog told reporters. 

“I’m sure that’s a guy I’ll be checking in with once in a while,” Landeskog said. “It’s nice to relate to somebody and for somebody to know what I’m talking about.”

There are two general ways to execute the transplant, which aims to restore a sort of hole where cartilage has essentially eroded, causing pain in the joints. One approach is to use donor cartilage from a cadaver; another is to first complete a biopsy of the patient’s own healthy cartilage and harvest it to then transplant it into the damaged area. Either way, the surgery — which exists thanks to advancements in the last two decades — requires sculpting the new cartilage to a film or membrane the shape of the defect where it needs to fit.

The irregular shape of the patella makes it among the most difficult areas to execute the surgery, doctors say.

“It’s not just round; it’s not just flat,” said Dr. Matthew Matava, a St. Louis Blues team physician who specializes in sports medicine and cartilage restoration at Washington University. In his experience, some insurance companies have been hesitant to approve cartilage grafts for the patella for that reason.

Matava said he generally puts the knee in a brace and locks it in a straight, extended position after the surgery. On Thursday morning, Landeskog posted a photo on Instagram saying the procedure went well and showing his right leg positioned in a brace the same way. The reason is to avoid compression or shear stress on the kneecap.

“The patella rides against the end of your femur bone. … It’s not going against normal, smooth surfaces,” Matava said. “The way (hockey players) push off and are gliding on the ice — even though they’re not jumping or running like a basketball player would — there’s a lot of shear back and forth as they bend their knee and explode and push off the skate.”

Kharrazi explained that minor damage can expand and worsen behind the patella. The doctors who spoke with The Post don’t know the precise details of Landeskog’s injury and can only speak generally about the nature of the injury, but this was likely the case for Landeskog. The captain continued playing in recent seasons after the initial skate blade incident. He even returned from a March 2022 procedure by the start of the playoffs a month later, helping the Avalanche win the Stanley Cup with a remarkable 22 points in 20 games on the injured knee.

“Almost like paint that chips off a wall or off a car, that (damaged) area gets bigger,” Kharrazi said.

During the rehab process, the new cartilage is growing into the impacted region. In order to be successful, the transplanted cartilage has to form a biological bond with the patella. As Matava described it, “the cells are sort of growing into the bone, and the bone is growing into the cells.”

The average recovery time is approximately a year, Frank said, although some patients take longer and some feel better more quickly. With Landeskog young (30), healthy and fit, he’s theoretically positioned for a faster, smoother rehab.

But again, the standard of recovery for a regular individual or lower-level athlete is different from the standard Landeskog is hoping to reach.

“We’re doing this to get you back to your life,” Frank tells patients. “To get you back to going up and down the stairs, playing with your kids or enjoying being outside with your family.”

Getting back to high-level competition is the “cherry on top,” she says.

It’ll be impossible to know whether the surgery was a true success or failure for another 9 to 12 months, when significant signs of progress should show. Landeskog said he hasn’t even ruled out playing in the 2024 playoffs yet. But this rehab process requires an intense level of commitment.

“There’s coming back at all, and there’s coming back at a high, NHL level where he’s the player he was of a world-class nature,” Matava said. Landeskog is plunging into the unknown, but Matava believes “he has everything going for him to get this to work.”

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