Open arthrotomy of the glenohumeral joint with synovectomy — incision into the shoulder joint to excise inflamed synovial tissue, with or without biopsy.

Verified May 8, 2026 · 6 sources ↓

Medicare: $605.22
Total RVUs: 18.12
Global, days: 90
Region: Shoulder

Drawn from AAPCMdclarityFindacodeCMS

Documentation requirements

What must appear in the operative or office note to support the claim.

Source · Editorial brief grounded in 6 cited references ↓

Diagnosis driving the synovectomy — specify condition (e.g., rheumatoid arthritis, PVNS, inflammatory arthritis) with supporting clinical history
Failed prior treatment documented — conservative measures, injections, or arthroscopic attempts that justify open approach
Operative note naming the surgical approach (e.g., deltopectoral, anterosuperior) — notes that say 'standard approach' are audit flags
Extent of synovial resection described — partial vs. complete synovectomy, specific compartments addressed
Biopsy documentation if tissue was sent to pathology — specimen label, laterality, and pathology order must match the operative note
Laterality clearly stated in both the operative note and the claim — LT or RT required for shoulder procedures

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 24 Unrelated E/M during global 25 Significant separate E/M 50 Bilateral procedure 51 Multiple procedures 52 Reduced services 57 Decision for surgery 58 Staged or related 59 Distinct service 62 Co-surgeons 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon AS PA/NP/CNS assistant LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 23105 describes an open surgical procedure in which the glenohumeral joint is entered through a direct incision, the synovium is inspected, and inflamed or diseased synovial tissue is excised. The goal is pain relief and restoration of motion in patients where synovial pathology — such as that seen in rheumatoid arthritis, pigmented villonodular synovitis (PVNS), or persistent inflammatory arthritis — has failed conservative or arthroscopic management. A tissue biopsy may be taken during the same session.

This is an open procedure, not arthroscopic. If synovectomy is performed arthroscopically at the shoulder, report 29823 instead. 23105 carries a 90-day global period, meaning all routine post-op care through day 90 is bundled. Unrelated E/M services in that window require modifier 24; a significant, separately identifiable E/M on the day of surgery requires modifier 25.

The procedure is performed almost exclusively by orthopedic surgeons. Site of service matters significantly here — HOPD and ASC payments differ substantially. See the Site of Service comparison table on this page for current 2026 rates.

RVU & reimbursement

Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	8.27
Practice expense RVU	8.13
Malpractice RVU	1.72
Total RVU	18.12
Medicare national rate	$605.22
Global period	90 days

Payment by site of service

Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.

Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026

Setting	Medicare rate (national)
Office (PFS non-facility) Procedure performed in physician's office	$605.22
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI A2) Ambulatory surgical center (freestanding)	$3,695.53

Common denial reasons

The recurring reasons claims for CPT 23105 get rejected.

Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓

Missing laterality modifier — LT or RT required; claims without one are routinely rejected by Medicare and most commercial payers
Bundling conflict when 23105 is billed same-day with arthroscopic shoulder codes — payers will question why both open and scope procedures were performed
Lack of medical necessity documentation — synovectomy requires evidence of failed conservative treatment; vague diagnoses like 'shoulder pain' without supporting pathology will trigger denial
Global period violations — post-op E/M visits billed without modifier 24 during the 90-day global are denied as already bundled
Upcoding to modifier 22 without adequate documentation — increased complexity claims require the operative note to quantify why work exceeded the typical case

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01What is the difference between CPT 23105 and CPT 29823?

23105 is open arthrotomy with synovectomy — a direct incision into the glenohumeral joint. 29823 is arthroscopic shoulder synovectomy. If the procedure was done through a scope, bill 29823. Billing 23105 for an arthroscopic case is a misrepresentation and an audit target.

02Does 23105 require a laterality modifier?

Yes. Always append LT or RT. The shoulder is a paired structure, and Medicare and most commercial payers will reject or suspend claims without a laterality modifier. Modifier 50 applies only if both shoulders are operated on in the same session, which is rare.

03What global period applies to 23105?

90-day global. The day before surgery, the surgery itself, and all routine post-op care through day 90 are bundled into the payment. E/M visits for unrelated problems during that window need modifier 24. A new, unrelated surgical procedure needs modifier 79.

04Can modifier 22 be used with 23105?

Yes, but document rigorously. Modifier 22 requires the operative note to specify what made the case substantially more work than typical — dense adhesions, prior surgical scarring, or unusual anatomy. A generic statement that the case was 'complex' will not support the upcode.

05Is a biopsy separately billable when performed during 23105?

No. When a synovial biopsy is taken as part of the open synovectomy, it is integral to the procedure and not separately reportable. Billing a biopsy code alongside 23105 for tissue taken during the same arthrotomy will be bundled by NCCI edits.

06When would modifier 58 apply to 23105?

If 23105 was planned as a staged follow-on to a prior shoulder procedure performed by the same surgeon — for example, a staged synovectomy after an initial diagnostic arthrotomy — modifier 58 signals a staged or related service during the prior procedure's global period.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira's AI scribe captures the surgical approach by name, the extent of synovial resection (partial vs. complete), compartments entered, biopsy status, and laterality directly from the surgeon's dictation. This prevents the two most common audit flags for 23105: operative notes that omit approach terminology and missing laterality documentation that triggers automatic claim rejection.

See how Mira captures CPT 23105 documentation