YOUR HEALTH: Fixing Sister’s knees

LA JOLLA, California – It's hard to keep up with 79-year-old Sister Margaret Castro these days.

Last year, knee pain made trips to her upstairs office excruciating.

"I would get to a third and then I'd have to hang on to the wall and I'd walk holding on to the wall to get to the door. and I never said anything to anybody."

Sister Margaret worked in leper colonies in India with Mother Teresa for 15 years as a girl.   She's tough, but her knee pain got to be too much.

She called Scripps orthopedic surgeon David Fabi who told her about the robotic surgery system.

A robotic-assisted system called Navio is helping doctors with total knee replacements in the operating room.   The technique was approved by the FDA in 2015

"It essentially allows us to customize the knee replacement to that patient's specific needs, the specific anatomy," said Dr. Fabi.

There's no pre-surgical MRI or CT scan.

Dr. Fabi has the Navio in the operating room.  Using sensors on the knee, it produces a 3-D image that helps him precisely align the knee replacement.

"We were hitting about, at best, 90 percent target rate. What the robotic technology and computer technology provides is that now we are able to achieve 98, 99 percent accuracy."

NEW TECHNOLOGY:   Dr. Fabi says doctors trace out the knee during the operation and the software formulates a 3D virtual model. This enables the surgeons to fit the implants to their anatomy and designate specific parameters.   "The pressures are equal throughout the knee," said DR. Fabi, "so that it moves more like a normal knee. This technology provides that information that we never had before."

Sister Margaret says she was out of the hospital in two days and back at work in three.

"When I come just to work every day, I don`t pay attention to my knee. I just go about my work, and I forget all about my knees, you know, and that's fantastic, you know!"

She says her knee is as good as it's ever been.

A nun's prayers answered.

If this story has impacted your life or prompted you or someone you know to seek or change treatments, please let us know by contacting Jim Mertens at or Marjorie Bekaert Thomas at