Mike Cox plans to lift his son, Thaddeus Cox, who will be 20 months old Thursday, and twirl him around like your normal proud dad.

It’s a moment that will challenge Cox, a former fullback with the Falcons who’s had three shoulder surgeries and will need shoulder replacement surgery down the road.

After five seasons in the NFL, Cox came to grips with his immortality and his health concerns before former San Francisco linebacker Chris Borland shined a light on health, safety and millions of dollars, the underbelly of the NFL, with his retirement at age 24.

What good was your NFL career if you can’t lift your infant son in the air, play catch and shoot baskets?

“I would have love to still be playing, but knowing that I’m in a constant state of pain, 24 hours a day,” said Cox, who returned to Georgia Tech to earn his degree. “It hurts. My mind is saying pridefully that I’d love to still be playing, but maybe it is for the best and that there is nothing majorly wrong.”

Cox played for the Kansas City Chiefs from 2008-10 and for the Falcons in 2011 and 2012. He played in 56 NFL games and made 29 starts.

He mostly was a blocker whose job was to smash into defenders and move then out of the way. His left shoulder eventually gave way.

“Toward the tail end of my career it started to impact my play,” Cox said. “If I had a defender on the outside I didn’t really have the strength to punch and recover as well.”

Shortly after the 2012 season, Cox learned that Thaddeus was on the way.

“I was going to have a little son,” Cox said. “I just thought more about being able to play with him and do fun stuff.

“Just typical father-and-son stuff. Now, I can’t really scratch the back of my head or wash my armpit properly. I’m just lucky that it’s my left one and not my throwing one so I can still play catch and shoot basketball and all of that fun stuff.”

The Falcons nearly reached the Super Bowl in his last season, but he knew trying to continue playing would be risky.

“It was definitely in the back of my mind,” Cox said of the long-term health concerns.

The football world stopped and took notice last week when Borland walked away from the game and possibly millions of dollars.

He cited that the money wasn’t worth the potential long-term health risks. In the previous week, four other players, all 30 and under, decided to retire.

Celebrated San Francisco linebacker Patrick Willis (30), Oakland running back Maurice Jones-Drew (29), Pittsburgh defensive end Jason Worilds (27) and Tennessee quarterback Jake Locker (26) all retired.

Willis said he could no longer play with the pain in his feet.

During his farewell news conference he said, “I pay attention to guys when they’re finished playing. It’s my health first and everything else just kind of makes sense around it.”

Willis, a seven-time Pro Bowler, was set to collect $20 million in base salaries over the final three years of his contract.

Worilds played five seasons and earned about $13 million. He was in position to make about $15 million and was sought by many teams, including the Falcons. However, he elected to pursue other interests, including his work with Jehovah’s Witnesses, according to the Pittsburgh Post-Gazette.

Jones-Drew played nine seasons and wasn’t productive anymore. Locker pointed to a lack of passion for the game.

Borland’s retirement caught the attention of Jeff Miller, the NFL’s senior vice president of health and safety policy.

“We respect Chris Borland’s decision and wish him all the best,” Miller said in a statement. “Playing any sport is a personal decision. By any measure, football has never been safer, and we continue to make progress with rule changes, safer tackling techniques at all levels of football, and better equipment, protocols and medical care for players. Concussions in NFL games were down 25 percent last year, continuing a three-year downward trend.”

Falcons outside linebacker O’Brien Schofield decided to continue playing on a bad knee that caused him to flunk the New York Giants’ physical in 2014 and cost him a two-year, $8 million contract. He signed a one-year, $1.7 million deal with the Falcons earlier this month after a second season with Seattle.

He never thought of retiring.

“Well, to each his own,” Schofield said. “Some guys’ injuries are probably more serious, life-threatening and long-term than others. Some have come to that conclusion and are comfortable with that decision.”

Schofield suffered a torn ACL on the first day of Senior Bowl practice in 2010. He believes that in a subsequent surgery, too much meniscus cartilage was removed.

“It started wearing down to the point where I could probably form arthritis, or there is probably some in there right now,” Schofield said. “It was tough to go through that because I felt I put my body of work out on the field just like anybody else. This is my job, and I was working to get a pay day.”

He had the pay day, but the Giants didn’t like his knee.

“Unfortunately, I was not able to sign that big deal with New York,” Schofield said. “But everything worked out and I was able to go back and play with my brothers in Seattle and I had a chance to compete for a second Super Bowl.”

He was a part of the rotation in Seattle, and the Falcons will have a special practice plan for Schofield.

“They are going to do a pretty good job managing my knee so that I can … not put too much on me through practice and training camp,” Schofield said. “Whatever workload that I can take on, I’m going to take on.”

Schofield, 27, a well-spoken young man from suburban Chicago, played with Borland at Wisconsin in 2009 and 2010.

“I still have a lot of football left in my tank,” Schofield said. “There are a lot of guys in this league that are playing with some type of injury, some type of setback. But that’s part of this game with the toughness factor.

“Can a guy be available? Can you play through injury? Can you play through the hurt and the pain? That’s what football has been all about since you were a kid. It’s nothing new.”

At the school’s Pro Day on Wednesday, Georgia coach Mark Richt was out on the field rooting on his 19 players. He stood past the 40-yard and shouted words of encouragement as they zoomed by.

He wants what’s best for his players.

“It’s just a matter of personal choice,” Richt said. “We had a pro scout, actually a director of recruiting, come in and talk to our guys. He said the NFL is the one of the greatest temporary jobs that you’ll ever have. It’s a temporary job.”

The scout emphasized education and told the players that they should prepare for the end of their temporary jobs in the offseason.

“There is going to be a rest of your life,” Richt said. “Even if you play eight or nine years, which is a long time, you’re only 30 years old. You still have a long way to go in life. You’ve got to have a plan for that.”

Cox has a plan.

He’s set to get his degree in business administration with a concentration in marketing May 2.

“I have been interviewing for medical-device sales,” Cox said. “So, it could be interesting. I’ve had an interview for joint-replacement devices which will be interesting because I’ll need a shoulder replacement myself, and that’s what I’ll be doing.

“It would be a good pitch to sell what I have inside of myself. I’ve always wanted to do something in the medical field with Dad being a doctor.”

By then, Cox hopes that Thaddeus is too heavy to lift and twirl around.