CPT Code 29870 (formerly 71020): Knee Arthroscopy with Synovectomy & Debridement

Correction: The code referenced (71020) is a legacy/invalid code. The current CPT code for this procedure is 29870.

CPT 29870: Arthroscopy, Knee, Diagnostic, with Synovectomy

Official Descriptor (AMA CPT 2024):

Arthroscopy, knee, diagnostic, with synovectomy (separate procedure)

Included Components (When Performed)

• Diagnostic arthroscopy (systematic joint inspection)
• Synovectomy (partial or complete removal of inflamed synovium)
• Debridement (loose bodies, cartilage flaps, fibrous tissue)
• Chondroplasty (mechanical smoothing of chondral lesions)
• Osteoplasty (bone contouring)
• Meniscectomy (partial, if separate from primary meniscal repair code)
• Excision of loose bodies

Critical Coding Rules

1. Bundling: 29870 includes diagnostic arthroscopy. Do not bill 29870 + 29871 (diagnostic only) together.
2. Synovectomy Requirement: Must document medical necessity for synovectomy (inflammatory arthritis, PVNS, synovial chondromatosis, hemophilia) — not routine "clean-up."
3. Meniscectomy: If meniscal repair (29880-29883) performed, partial meniscectomy in same compartment is bundled. Different compartment may be reported with -59/XS modifier.
4. Chondroplasty/Osteoplasty: Included in 29870 when performed with synovectomy. Not separately reportable.
5. Loose Body Excision: Included. If extensive (separate incision, significant time), may justify 29874 with modifier.

Common Indications

• Rheumatoid arthritis / inflammatory synovitis
• Pigmented villonodular synovitis (PVNS)
• Synovial chondromatosis
• Hemophilic arthropathy
• Post-traumatic synovitis refractory to conservative care

Documentation Requirements

• Pre-op diagnosis supporting synovectomy
• Operative report: compartments visualized, synovial pathology described, extent of synovectomy, additional procedures
• Photos/video clips supporting medical necessity

Reimbursement Context (2024 Medicare National Average)

• Facility (ASC/Hospital Outpatient): ~$1,200-1,500 (APC 5113)
• Professional (Surgeon): ~$600-800 (RVU ~10-12)
• Varies by geography, site-of-service, payer contracts

Always verify current CPT descriptors, NCCI edits, and payer policies before coding. The code 71020 is obsolete and should not be used.