AJ Starsiak was stretching at his gym, preparing to do squats, when he felt an alarming pop in his back.

The 39-year-old father, who plays softball and ice hockey and spends weekends off-roading, was no stranger to minor injuries. But the anti-inflammatory drugs prescribed by his primary care physician only gave Starsiak temporary relief. Over the next few months, his hips stiffened, and he began to lose sensation and muscle mass in his leg.

Then, during a business trip, the pain caused Starsiak to reach a breaking point.

"I could not walk from one gate to the next at the airport and ended up having a breakdown, crying because I was in so much pain," Starsiak said.

After multiple doctor visits, including a trip to the emergency room, an MRI revealed the cause: a 2-centimeter cyst lodged on the front side of a nerve, tucked beneath a joint in his spine. Its location made it particularly difficult to treat.

A physician near his home in Orange County referred Starsiak to Corey Walker, MD, an assistant professor of Neurosurgery and Orthopaedics at Cedars-Sinai, who specializes in minimally invasive and complex spine cases.

Starsiak, a medical device salesman with a focus on orthopedic products, was familiar with surgical options and trusted his instincts in choosing Walker to oversee his care.

"When I met Dr. Walker, I immediately knew he was the right surgeon-someone of integrity who listened carefully and was deeply passionate about his craft," Starsiak said.

Cyst Removal Without Spinal Fusion

Walker performs endoscopic spine surgery, a minimally invasive technique that uses a small endoscope-about the width of a pen-to navigate hard-to-reach places inside the body. Compared with traditional surgery, the minimally invasive approach typically results in smaller incisions, less tissue damage and faster recovery.

In Starsiak's case, the cyst was compressing nerves against his spinal canal, interfering with their ability to send signals between his brain and leg. That pressure can lead to loss of strength, sensation and coordination.

Removing the cyst would be challenging. In order to access the nerve and underlying cyst, a surgeon typically would need to remove a spinal joint and fuse the vertebrae with rods and screws to stabilize them.

"That would have been a life-altering operation for someone his age," Walker said. "Fusion puts added stress on surrounding joints and can lead to future surgeries."

Instead, Walker took a different approach.

Using an ultra-minimally invasive endoscopic procedure, Walker accessed the cyst through an endoscope with a small camera attached. After locating the affected nerve, he and his team were able to use the endoscope to guide them in removing the cyst-without cutting muscle, removing the joint or injuring the nerve.

"We had what felt like an impossible task," Walker said. "I'm proud that Cedars-Sinai is able to treat patients who have complex cases."

For Starsiak, avoiding fusion was critical.

"I was worried a fusion would significantly hamper-if not end-my ability to play sports and lift weights," he said.

Life-Changing Relief

When Starsiak woke up from the procedure, he immediately felt relieved of the pain and pressure, as if a rock had been removed from his back.

His recovery took about eight weeks, and he focused on restoring mobility and strength in his hips, legs and back. Today, Starsiak is back to his normal routine-playing sports, off-roading and lifting weights at the squat rack.

The experience also changed his mindset.

Before the injury, Starsiak said, he measured success largely by career advancement. As a father of two, losing his mobility forced him to reconsider his priorities.

"The second you lose your health, you realize none of the other things really matter," he said. "You can't enjoy success if you're not healthy."

For Walker, that impact is what makes the work meaningful.

"As a neurosurgeon, it's incredible to hone your craft-to work with your hands and see a problem fixed by the end of surgery," he said. "But what's even more rewarding is hearing later how it's changed someone's life-that's the best part."

Read more from the Cedars-Sinai Newsroom: Defying the Odds - Father's Love Leads to Life-Changing Surgery