Remove knee joint lining

Hospitals publish their machine-readable files (MRFs) the way they choose. A single procedure code can appear with very different prices depending on what's being charged:

• Global price — facility + implant + anesthesia + surgeon. This is what you'd actually be billed.
• Professional fee only — surgeon's portion. Often $500–$2,500 for a major procedure that costs $20K+ globally.
• Facility fee only — operating room and recovery, no implant or surgeon.
• Per-unit / per-minute charges — e.g. anesthesia time billed at $0.68/min appearing under a CPT code.
• Rate multipliers — values like 0.85 meaning "85% of Medicare" rather than dollars.

We filter the most obvious artifacts (under $50, or 25× above the median), but rows in the $500–$2K range for a major procedure are typically professional-only and we can't always tell. Use the median and high-end as the realistic range; treat very low rows as partial-cost line items, not full bills.