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Official Description

Arthroscopy, shoulder, surgical; synovectomy, complete

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

Arthroscopy of the shoulder is a minimally invasive surgical procedure that allows for the examination and treatment of various shoulder joint conditions. The specific procedure described by CPT® Code 29821 involves a complete synovectomy, which is the surgical removal of the synovial membrane lining the shoulder joint. This procedure is typically indicated for patients with significant synovial disease, such as synovitis or other inflammatory conditions affecting the shoulder. During the procedure, the patient is positioned either in a lateral decubitus position, where they lie on their side with the affected arm suspended, or in a beach chair position, which allows for optimal access to the shoulder joint. The use of skin traction helps to stabilize the arm and improve visibility during the surgery. The procedure begins with the creation of anterior and posterior portal incisions, through which an infusion pump is used to introduce sterile saline solution into the joint, expanding the joint space for better visualization. Following a diagnostic arthroscopy, the surgeon explores the joint for any synovial defects or disease. If necessary, additional portal incisions are made to facilitate the introduction of surgical instruments. The synovial membrane is then carefully resected using specialized tools, and any bleeding is managed through techniques such as radiofrequency or electrocautery. Once the complete synovectomy is performed, the fluid is drained from the joint, the incisions are closed, and a dressing is applied to promote healing.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The procedure described by CPT® Code 29821 is indicated for patients experiencing significant synovial disease or conditions affecting the shoulder joint. The following are specific indications for performing a complete synovectomy:

  • Synovitis - Inflammation of the synovial membrane, which can cause pain and swelling in the shoulder joint.
  • Rheumatoid Arthritis - A chronic inflammatory disorder that can lead to synovial membrane thickening and joint damage.
  • Joint Effusion - Accumulation of excess fluid in the joint space, often associated with inflammatory conditions.
  • Synovial Cysts - Fluid-filled sacs that can develop in the synovial membrane, causing discomfort and limiting joint movement.

2. Procedure

The complete synovectomy procedure involves several key steps, each critical to the successful outcome of the surgery. The following outlines the procedural steps as described:

  • Step 1: Patient Positioning - The patient is positioned in either a lateral decubitus position or a beach chair position to provide optimal access to the shoulder joint. In the lateral decubitus position, the affected arm is suspended to facilitate the procedure.
  • Step 2: Portal Incision - Anterior and posterior portal incisions are made over the shoulder joint to allow access for the arthroscopic instruments. These incisions are strategically placed to minimize tissue damage and enhance visibility.
  • Step 3: Joint Distension - An infusion pump is utilized to introduce sterile saline solution into the shoulder joint, expanding the joint space. This distension is crucial for providing a clear view of the joint structures during the procedure.
  • Step 4: Diagnostic Arthroscopy - A diagnostic arthroscopy is performed to explore the shoulder joint and assess the extent of synovial disease or defects. This step allows the surgeon to visualize the synovial membrane and any associated abnormalities.
  • Step 5: Additional Portals - If necessary, additional portal incisions are made to facilitate the introduction of surgical tools, ensuring adequate access to the surgical site for effective synovial membrane removal.
  • Step 6: Synovial Resection - The synovial membrane is resected using a resector, which is a specialized instrument designed for this purpose. Care is taken to remove all damaged synovium while preserving surrounding structures.
  • Step 7: Hemostasis - Any bleeding that occurs during the procedure is controlled using techniques such as radiofrequency or electrocautery, ensuring a clear surgical field and minimizing complications.
  • Step 8: Closure and Dressing - After the complete synovectomy is performed, the saline solution is drained from the shoulder joint. The incisions are then closed, and a dressing is applied to protect the surgical site and promote healing.

3. Post-Procedure

Post-procedure care following a complete synovectomy includes monitoring for any signs of complications, such as infection or excessive swelling. Patients are typically advised to rest the shoulder and may be prescribed pain management strategies. Physical therapy may be recommended to restore range of motion and strength in the shoulder joint as part of the recovery process. Follow-up appointments are essential to assess healing and ensure that the shoulder is recovering appropriately.

Short Descr SHO ARTHRS SRG COMPL SYNVCT
Medium Descr SURGICAL ARTHROSCOPY SHOULDER COMPL SYNOVECTOMY
Long Descr Arthroscopy, shoulder, surgical; synovectomy, complete
Status Code Active Code
Global Days 090 - Major Surgery
PC/TC Indicator (26, TC) 0 - Physician Service Code
Multiple Procedures (51) 3 - Special payment adjustment rules for multiple endoscopic procedures apply.
Bilateral Surgery (50) 1 - 150% payment adjustment for bilateral procedures applies.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 2 - Payment restriction for assistants at surgery does not apply to this procedure...
Co-Surgeons (62) 1 - Co-surgeons could be paid, though supporting documentation is required...
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Endoscopic Base Code 29805  Arthroscopy, shoulder, diagnostic, with or without synovial biopsy (separate procedure)
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Hospital Part B services paid through a comprehensive APC
ASC Payment Indicator Surgical procedure on ASC list in CY 2007; payment based on OPPS relative payment weight.
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) P8A - Endoscopy - arthroscopy
MUE 1
CCS Clinical Classification 162 - Other OR therapeutic procedures on joints

This is a primary code that can be used with these additional add-on codes.

29826 Addon Code MPFS Status: Active Code APC N ASC N1 CPT Assistant Article Arthroscopy, shoulder, surgical; decompression of subacromial space with partial acromioplasty, with coracoacromial ligament (ie, arch) release, when performed (List separately in addition to code for primary procedure)
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
RT Right side (used to identify procedures performed on the right side of the body)
AS Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery
LT Left side (used to identify procedures performed on the left side of the body)
51 Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d).
22 Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m service.
50 Bilateral procedure: unless otherwise identified in the listings, bilateral procedures that are performed at the same session, should be identified by adding modifier 50 to the appropriate 5 digit code. note: this modifier should not be appended to designated "add-on" codes (see appendix d).
58 Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78.
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
78 Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.)
79 Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.)
80 Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s).
82 Assistant surgeon (when qualified resident surgeon not available): the unavailability of a qualified resident surgeon is a prerequisite for use of modifier 82 appended to the usual procedure code number(s).
GC This service has been performed in part by a resident under the direction of a teaching physician
SG Ambulatory surgical center (asc) facility service
XE Separate encounter, a service that is distinct because it occurred during a separate encounter
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
Date
Action
Notes
2021-01-01 Changed Short and medium descriptions changed.
Pre-1990 Added Code added.
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