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Official Description

Arthroscopy, knee, surgical; for infection, lavage and drainage

© Copyright 2025 American Medical Association. All rights reserved.

Common Language Description

A surgical arthroscopy of the knee, designated by CPT® Code 29871, is a minimally invasive procedure aimed at addressing infections within the knee joint, commonly known as septic arthritis, as well as severe cases of arthritis. This procedure involves the use of an arthroscope, a specialized instrument equipped with a camera and light, which allows for direct visualization of the internal structures of the knee. The procedure begins with the creation of small incisions, referred to as portal incisions, on the medial and lateral sides of the knee joint. Through one of these incisions, the arthroscope is introduced, enabling the surgeon to examine the joint for any signs of disease, injury, or infection. A second portal is utilized for the insertion of a cannula, through which a saline solution is introduced to flush the joint. This lavage process helps to cleanse the joint of any infectious material or debris. Additionally, antibiotics or other therapeutic solutions may be instilled into the joint to combat infection. After the joint has been adequately treated, the solutions are drained, and the instruments are removed. The procedure concludes with the closure of the portal incisions, or alternatively, a drain may be placed to facilitate further drainage if necessary. This comprehensive approach ensures effective management of knee joint infections and contributes to the overall recovery of the patient.

© Copyright 2025 Coding Ahead. All rights reserved.

1. Indications

The procedure described by CPT® Code 29871 is indicated for specific conditions affecting the knee joint, particularly those that involve infection or severe inflammatory processes. The following are the primary indications for performing this arthroscopic procedure:

  • Infection - The procedure is performed to treat infections within the knee joint, commonly referred to as septic arthritis, which can lead to significant pain and joint dysfunction.
  • Severe Arthritis - It is also indicated for cases of severe arthritis where infection may be a concern, necessitating intervention to alleviate symptoms and prevent further joint damage.

2. Procedure

The surgical procedure for CPT® Code 29871 involves several critical steps to ensure effective treatment of the knee joint infection. The following outlines the procedural steps:

  • Step 1: Portal Incision Creation - The procedure begins with the surgeon making small incisions, known as portal incisions, on both the medial and lateral aspects of the knee joint. These incisions are strategically placed to provide access to the joint while minimizing tissue damage.
  • Step 2: Introduction of the Arthroscope - An arthroscope, which is a thin tube equipped with a camera and light source, is then inserted through one of the portal incisions. This allows the surgeon to visualize the internal structures of the knee joint on a monitor, facilitating a thorough examination.
  • Step 3: Insertion of the Cannula - A cannula is introduced through the second portal incision. This instrument serves as a conduit for the introduction of fluids into the joint space.
  • Step 4: Lavage of the Joint - The joint is flushed with a saline solution through the cannula. This lavage process is essential for removing infectious material, debris, and any inflammatory substances present in the joint.
  • Step 5: Treatment of Infection - Following the lavage, the surgeon may instill antibiotics or other therapeutic solutions directly into the joint to address the infection and promote healing.
  • Step 6: Drainage of Solutions - After the treatment, the solutions used during the procedure are drained from the joint to ensure that any residual infectious material is removed.
  • Step 7: Removal of Instruments - Upon completion of the procedure, the arthroscope, cannula, and any other instruments utilized are carefully removed from the joint.
  • Step 8: Closure of Incisions - Finally, the portal incisions are either closed with sutures or a drain may be placed through one or more of the portals to facilitate further drainage if necessary.

3. Post-Procedure

After the completion of the arthroscopy for infection, patients can expect specific post-procedure care and considerations. It is essential to monitor the surgical site for any signs of infection or complications. Patients may be advised to rest and limit weight-bearing activities on the affected knee to promote healing. Pain management strategies, including prescribed medications, may be implemented to alleviate discomfort. Follow-up appointments are typically scheduled to assess the recovery process and ensure that the infection has been adequately addressed. If a drain has been placed, instructions will be provided for its care and eventual removal. Overall, adherence to post-procedure guidelines is crucial for optimal recovery and to prevent recurrence of infection.

Short Descr KNEE ARTHROSCOPY/DRAINAGE
Medium Descr ARTHROSCOPY KNEE INFECTION LAVAGE & DRAINAGE
Long Descr Arthroscopy, knee, surgical; for infection, lavage and drainage
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) 1 - Statutory payment restriction for assistants at surgery applies to this procedure...
Co-Surgeons (62) 0 - Co-surgeons not permitted for this procedure.
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Endoscopic Base Code 29870  Arthroscopy, knee, 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 149 - Arthroscopy

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

G0289 Add-on Code Medicare Coverage: Carrier Priced MPFS Status: Active Code APC N Arthroscopy, knee, surgical, for removal of loose body, foreign body, debridement/shaving of articular cartilage (chondroplasty) at the time of other surgical knee arthroscopy in a different compartment of the same knee
LT Left side (used to identify procedures performed on the left side of the body)
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
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).
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).
54 Surgical care only: when 1 physician or other qualified health care professional performs a surgical procedure and another provides preoperative and/or postoperative management, surgical services may be identified by adding modifier 54 to the usual procedure number.
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.
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.
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.
77 Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 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).
AG Primary physician
CR Catastrophe/disaster related
GC This service has been performed in part by a resident under the direction of a teaching physician
GW Service not related to the hospice patient's terminal condition
GZ Item or service expected to be denied as not reasonable and necessary
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
2019-01-01 Note AMA Guidelines changed.
2015-01-01 Note AMA Guidelines changed.
Pre-1990 Added Code added.
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