2025 CPT code 27334

Arthrotomy, knee, with synovectomy, anterior OR posterior

Modifiers may be applicable. Refer to guidelines and individual payer rules.

Medical necessity should be supported by documentation of persistent knee pain, swelling, and/or limited range of motion due to synovitis refractory to conservative treatment. Specific diagnosis causing the synovitis (e.g., rheumatoid arthritis, PVNS, meniscal tear) should be documented. The chosen surgical approach (anterior or posterior) should be justified based on the location of affected synovium.

In simple words: This procedure involves making an incision in your knee joint to remove inflamed or damaged tissue called the synovium, which is causing pain and difficulty moving your knee. This is done either from the front or back of your knee.

This code describes a surgical procedure where an incision is made into the knee joint (arthrotomy) to remove the synovium (synovectomy) from either the front (anterior) or back (posterior) of the knee.It is used to treat conditions causing pain and impaired movement due to inflammation or damage to the synovium. The procedure includes making the incision, removing the affected synovial tissue, flushing the joint with sterile saline, controlling bleeding, and closing the incision in layers.

Example 1: A patient with rheumatoid arthritis experiencing persistent knee pain and swelling despite medical management undergoes anterior synovectomy via arthrotomy., A patient with a torn meniscus has localized posterior synovitis and undergoes posterior synovectomy during knee arthroscopy (code separately with appropriate arthroscopy code). In this scenario, modifier 51 would be applied to the 27334 code because this procedure was performed in conjunction with another surgical procedure., A patient with pigmented villonodular synovitis (PVNS) affecting the anterior knee joint undergoes an extensive anterior synovectomy via arthrotomy to remove the abnormal synovial tissue.

Operative report detailing the approach (anterior or posterior), extent of synovectomy, any associated procedures, findings, and complications. Pre- and postoperative diagnoses, supporting clinical documentation justifying medical necessity (e.g., imaging studies, failed conservative treatments).

** Code 27335 is used for BOTH anterior AND posterior synovectomy during the same surgical session. If significant additional procedures are performed (e.g., meniscus repair, ligament reconstruction), those should be coded separately. If a cast or splint is applied, the application of the first cast, splint, or traction is included and should not be reported separately.

  • Global Days : Refer to payer guidelines for global days.
  • Specialties:Orthopedic Surgery, Sports Medicine
  • Place of Service:Ambulatory Surgical Center, Hospital - Inpatient, Hospital - Outpatient
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