Open arthrotomy of the acromioclavicular or sternoclavicular joint, performed for synovectomy, biopsy, or removal of loose bodies.

Verified May 8, 2026 · 6 sources ↓

Medicare: $443.56
Total RVUs: 13.28
Global, days: 90
Region: Shoulder

Drawn from CMSAAPCAAOS

Documentation requirements

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

Source · Editorial brief grounded in 6 cited references ↓

Specify which joint was entered: acromioclavicular or sternoclavicular — the code covers both but the operative note must name the joint.
Document the indication for arthrotomy (e.g., synovitis, loose body, suspected septic joint, biopsy of synovium).
Describe the surgical approach and capsular entry, not just 'standard approach' — audit teams flag generic language.
Record all findings within the joint (synovial hypertrophy, loose bodies, cartilage status) and all procedures performed during arthrotomy.
If modifier 22 is appended, document specifically what made the work substantially greater than typical — scarring, prior hardware, anatomic distortion.
Laterality must be documented and must match the LT or RT modifier on the claim.

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 51 Multiple procedures 57 Decision for surgery 58 Staged or related 59 Distinct service 62 Co-surgeons 76 Repeat, same physician 77 Repeat, another physician 78 Unplanned return — related 79 Unrelated during global LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 23101 describes an open surgical incision into either the acromioclavicular (AC) or sternoclavicular (SC) joint for purposes such as synovectomy, joint inspection, biopsy, or removal of loose or foreign bodies. It is not a resection arthroplasty — that's a separate code family. The procedure requires direct exposure of the joint capsule, arthrotomy, and closure, distinguishing it from purely arthroscopic or injection-based approaches.

The 90-day global period means all routine post-op care, wound checks, and related E/M visits through day 90 are bundled into the surgical fee. Any unrelated visit in that window needs modifier 24; a significant, separately identifiable same-day E/M needs modifier 25. If a decision for surgery was made at the same encounter, append modifier 57 to the E/M — required for 90-day global procedures.

Noting the AAOS Global Service Data guidance: code 29824 (arthroscopic distal clavicle excision) bundles 23101 as an included service. If both are performed on the same shoulder at the same encounter, 23101 cannot be billed separately — it's considered integral to 29824. Confirm current NCCI edits before billing these together under any circumstance.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	5.58
Practice expense RVU	6.5
Malpractice RVU	1.2
Total RVU	13.28
Medicare national rate	$443.56
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	$443.56
HOPD (APC 5113) Hospital outpatient department	$3,342.87
ASC (PI A2) Ambulatory surgical center (freestanding)	$1,644.87

Common denial reasons

The recurring reasons claims for CPT 23101 get rejected.

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

Bundling into 29824 (arthroscopic distal clavicle excision) when both procedures are billed for the same shoulder on the same date.
Missing or mismatched laterality — claim has LT but operative note documents right shoulder, or modifier absent entirely.
Insufficient medical necessity documentation: no diagnosis supporting open arthrotomy rather than a less invasive approach.
Modifier 25 missing when a significant E/M is billed on the same date as the surgical procedure.
Global period violations — post-op E/M billed without modifier 24 during the 90-day global window.

Frequently asked questions

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

01Can 23101 be billed with 29824 on the same date?

No. AAOS Global Service Data lists 23101 as included in 29824. Billing both for the same shoulder on the same date will trigger a bundling edit. If genuinely distinct, substantial documentation is required and payer policy should be confirmed before appending modifier 59.

02Which modifier indicates laterality — and is it required?

Use LT for left shoulder and RT for right shoulder. Medicare requires laterality modifiers on paired structures. Missing or incorrect laterality is a common clean-claim failure point.

03Does 23101 cover both AC and SC joint procedures?

Yes — the code covers open arthrotomy of either the acromioclavicular or the sternoclavicular joint. The operative note must specify which joint was entered; the claim code is the same for both.

04What modifier applies if a same-day E/M resulted in the decision to perform this surgery?

Append modifier 57 to the E/M code. Because 23101 carries a 90-day global period, any E/M where the decision for surgery was made — typically the day of or day before — requires modifier 57 to be separately payable.

05Is an assistant surgeon payable for 23101?

CMS assigns a payment restriction indicator to this code. Check the PFS indicator for 23101 — if it is '0', supporting documentation establishing medical necessity must be submitted for assistant-at-surgery payment to apply.

06How does the 90-day global period affect billing for post-op complications?

A return to the OR for a related complication within 90 days uses modifier 78 on the subsequent procedure — no new global period starts. An unrelated procedure in the same window uses modifier 79 and starts a new 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 joint name (AC vs. SC), surgical indication, approach description, intraoperative findings, and all procedures performed during arthrotomy directly from dictation. This prevents the most common audit flag — operative notes that fail to specify the joint entered or describe findings in generic terms — and ensures the laterality in the note matches what's billed.

See how Mira captures CPT 23101 documentation