Glossary · Clinical

Total shoulder arthroplasty (TSA)

Total shoulder arthroplasty (TSA) is a surgical procedure that replaces both the proximal humerus (ball) and glenoid (socket) with prosthetic components to relieve pain and restore function in a severely damaged shoulder joint. It is the third most commonly replaced joint in the U.S., after the hip and knee.

Verified May 8, 2026 · 7 sources ↓

Drawn from CMSPalmetto GBAAAPCAAOS

Definition

Source · Editorial summary grounded in 7 cited references ↓

TSA involves resecting the humeral head and preparing the glenoid fossa, then implanting matched prosthetic components to reconstruct the glenohumeral joint. Two constructs fall under this umbrella: anatomic TSA, which replicates native joint geometry, and reverse TSA (rTSA), which transposes the ball and socket—attaching a glenosphere to the scapula and a humeral cup to the proximal humerus. Despite the biomechanical difference, both are reported with CPT 23472 under current AMA guidance.

Medicare coverage for TSA is governed by LCD L39956 and companion Billing & Coding Article A59878. Coverage requires documented failure of conservative treatment and evidence of one qualifying condition: glenohumeral osteoarthritis, post-traumatic arthritis, rheumatoid arthritis, osteonecrosis, or cuff-tear arthropathy. Medical necessity must be supported by relevant history, physical examination findings, and imaging or diagnostic test results retained in the medical record.

U.S. primary shoulder arthroplasty volume grew more than 103% between 2011 and 2017, driving heightened scrutiny from Recovery Auditors, CERT contractors, and MACs. Recent evidence supports outpatient TSA in appropriately selected patients; when admission is required, the two-midnight rule applies.

Why it matters

Coding TSA incorrectly—most often by selecting a hemiarthroplasty code when both components were replaced, or vice versa—creates a direct reimbursement error and flags the claim for audit. Because CMS and its auditing contractors (Recovery Auditor, CERT) actively review TSA claims due to high procedure volume, insufficient documentation of conservative-treatment failure or a qualifying diagnosis leads to post-payment recoupment. Distinguishing between a primary procedure (CPT 23472), a single-component revision (CPT 23473), and a both-component revision (CPT 23474) also materially changes reimbursement and must be matched exactly to operative documentation.

Common mistakes

Where people most often go wrong with this concept.

Source · Editorial brief grounded in cited references ↓

Reporting a hemiarthroplasty code when the operative note confirms both glenoid and humeral components were implanted—CPT 23472 is required whenever both components are replaced, regardless of whether the construct is anatomic or reverse.
Using CPT 23473 (single-component revision) when the surgeon revised both the humeral and glenoid components—that scenario requires CPT 23474.
Submitting the claim without ICD-10-CM codes that affirmatively support medical necessity (e.g., omitting the laterality-specific arthritis or osteonecrosis code and using only a symptom code such as shoulder pain).
Failing to document failed conservative management before surgery; LCD L39956 requires evidence that non-operative treatment was attempted and insufficient.
Missing laterality in both the operative note and the ICD-10-CM code selection, which triggers coding compliance risk and potential claim denial.
Bundling separately billable concurrent procedures that are subject to NCCI edits with CPT 23472 without verifying edit status and applying a modifier only when a valid modifier indicator applies.
Omitting the two-midnight rule analysis when the patient is admitted postoperatively, or failing to document the clinical expectation of a two-midnight stay in the admission order and progress notes.

Related codes

Codes commonly involved when this concept appears in practice.

CPT

Modifiers

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 7 cited references ↓

01Is reverse total shoulder arthroplasty billed with a different CPT code than anatomic TSA?

No. Both anatomic and reverse TSA are reported with CPT 23472, which covers replacement of both the glenoid and proximal humerus regardless of which construct is used. The operative note should still specify the construct type for clinical accuracy and audit defensibility.

02What ICD-10-CM diagnosis codes support medical necessity for TSA under Medicare LCD L39956?

Qualifying diagnoses include glenohumeral osteoarthritis (M19.011/M19.012), post-traumatic arthritis, rheumatoid arthritis (M05.7xx), osteonecrosis of the humeral head (M87.02x), and rotator cuff tear arthropathy (M75.1xx). Laterality-specific codes are required; symptom-only codes such as shoulder pain are insufficient to establish medical necessity.

03When should CPT 23473 be used instead of CPT 23472?

Use CPT 23473 when the surgeon revises only one component—either the humeral or the glenoid—of a previously placed total shoulder arthroplasty. Use CPT 23474 when both components are revised. CPT 23472 applies only to primary (first-time) total shoulder replacements.

04Can TSA be performed in an ambulatory surgery center (ASC) and billed to Medicare?

CMS added total shoulder arthroplasty to the ASC covered procedures list, but facility and payer policy details evolve. Verify current ASC payment eligibility with your MAC before scheduling, as some contractors have issued specific guidance and certain inpatient-only list questions have generated active forum discussion among coders.

05What documentation does Medicare require to support a TSA claim?

LCD L39956 requires the medical record to include relevant history, physical examination findings, imaging results, and evidence that conservative treatment was tried and failed, unless the clinical situation makes conservative care inappropriate. All records must be available to the MAC on request.

06Which modifier should be appended if the patient returns to the OR for a complication during the TSA global period?

Append modifier 78 (Unplanned Return to the Operating Room for a Related Procedure During the Postoperative Period). Only the intraoperative portion of that return visit is reimbursed, and the global period is not reset. If the return procedure is unrelated to the original TSA, use modifier 79 instead.

Sources & references

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

Mira AI Scribe

When Mira captures a TSA encounter, verify and flag the following before the note is finalized: 1. COMPONENT DOCUMENTATION — The operative note must explicitly state that both the humeral head and glenoid were resected and replaced. 'Total shoulder replacement' alone is insufficient; the note should name each component and the implant system used. This drives CPT 23472 vs. 23470 (hemi) selection. 2. CONSTRUCT TYPE — Record whether anatomic or reverse TSA was performed. Both map to CPT 23472 under current AMA guidance, but the distinction is clinically and potentially auditably relevant; capture it explicitly. 3. LATERALITY — Confirm left or right is documented in the body of the note and matches the ICD-10-CM code selected (e.g., M19.011 right glenohumeral OA vs. M19.012 left). 4. QUALIFYING DIAGNOSIS — Surface the primary structural diagnosis (OA, post-traumatic arthritis, RA, osteonecrosis, cuff-tear arthropathy) from history and imaging. Do not lead with a symptom code; the structural diagnosis establishes LCD L39956 medical necessity. 5. CONSERVATIVE TREATMENT FAILURE — Confirm the note references prior non-operative treatment (physical therapy, injections, NSAIDs) and its inadequacy. If absent, flag for surgeon addendum before claim submission. 6. REVISION FLAG — If any component is being exchanged rather than placed for the first time, escalate to CPT 23473 or 23474 and prompt the surgeon to specify whether one or both components are revised. 7. SITE OF SERVICE & ADMISSION — If the patient is admitted, prompt documentation of the two-midnight clinical expectation in the admission order.

See Mira's approach

Reverse total shoulder arthroplasty (rTSA) is a surgical procedure that inverts the normal ball-and-socket geometry of the glenohumeral joint, placing a metal ball on the glenoid and a socket on the proximal humerus, enabling the deltoid muscle to compensate for a non-functional rotator cuff. It is reported with CPT 23472 and is the standard surgical option for rotator cuff tear arthropathy and massive irreparable rotator cuff tears with pseudoparalysis.

Hemiarthroplasty Clinical

Hemiarthroplasty is a partial joint replacement in which only one articular surface is resurfaced with a prosthesis—most commonly the femoral head in the hip or the proximal humerus in the shoulder—while the native opposing surface is left intact.

Glenohumeral joint Anatomy

The glenohumeral joint is the ball-and-socket articulation between the humeral head and the glenoid fossa of the scapula—the primary joint of the shoulder complex. It is the most mobile, and consequently the least inherently stable, joint in the human body.

Local Coverage Determination (LCD) Compliance

A Local Coverage Determination (LCD) is a regional Medicare policy issued by a Medicare Administrative Contractor (MAC) that defines when a specific service, procedure, or supply is considered reasonable and medically necessary within that contractor's jurisdiction.