Actress Angelica Panganiban is currently battling  avascular necrosis.

She revealed this in her most recent vlog, sharing how it took her by surprise.

She said, "Nakaramdam ako ng awa sa sarili ko na, 'Bakit ako, bakit sa akin nangyari ito?'

But what is it exactly?

According to the Mayo Clinic website, Avascular necrosis is the death of bone tissue due to a lack of blood supply. Also called osteonecrosis, it can lead to tiny breaks in the bone and cause the bone to collapse. 

Anyone can be affected. But the condition is most common in people between the ages of 30 and 50.

Avascular necrosis is also associated with long-term use of high-dose steroid medications and too much alcohol.

The 37-year-old mother shared how it all started with her feeling a bit of pain around the hip area during her pregnancy with daughter Amila Sabine Homan.

"Six months into pregnancy, meron na akong mga nararamdamang sakit sa may hips," she recalled.

"Hindi ko actually ma-pinpoint noon kung sa hips, sa leg, sa likod or sa puwitan.” 

She added, "Nagtanong-tanong ako sa mga doktor and friends ko na naging mommy na rin, and lahat naman sila sinasabi na it’s part of pregnancy.”

"So nung nanganak ako, wala rin talaga akong time na pansinin kung ano ba talaga yung mga masakit sa katawan ko."

Angelica thought the pain would eventually go away.

It didn’t.

The pain actually doubled following a recent trip -- to the point where she could hardly walk. 

Initially, she tried therapy. It actually worked for a while but the pain returned with a vengeance. It became more persistent.

It was then that Angelica and fiancé Gregg Homan, decided to visit a bone specialist.

They were told what it is exactly that is ailing her. 

"Namatay na yung mga bones ko sa balakang. Kaya pala hirap na ako maglakad," Angelica said.

She is now undergoing treatment.