Does synovial biopsy provide diagnostic value in undifferentiated inflammatory arthritis?

Currently, a synovial biopsy cannot reliably distinguish undifferentiated inflammatory arthritis. Work on this topic is ongoing, and there is reason to hope that biopsy findings may someday provide useful information regarding the pathology and treatment of various types of arthritis.

Donlin et al., ...

Curious what the 53% who rarely send for synovial biopsy are looking for or how they are utilizing them outside of a research setting?