CurrentPremera BluecrossPolicy 7.01.549

Knee Arthroscopy in Adults

Criteria and documentation requirements for when elective knee arthroscopy procedures for adults (age 19+) are reviewed as medically necessary, including site-of-service guidance and procedure-specific indications (meniscal tear, ACL/PCL repair, debridement, osteochondral defects, chondromalacia, synovial disorders).

Policy Summary

PayerPremera Bluecross

PolicyKnee Arthroscopy in Adults

Policy CodePolicy 7.01.549

Change TypeCriteria revisionscoding updates

Effective DateDec. 1, 2025

Next Review DateN/A

Key ActionObtain and document diagnostic imaging within 12 months and evidence of failed conservative therapy for the required duration before requesting authorization.

SourceLink

POLICY UPDATE CHANGES

Removed rheumatoid arthritis as a condition for which arthroscopic debridement, drainage, or lavage is considered medically necessary and removed criteria for arthroscopic excision of popliteal cyst.

Corrected policy criteria for intra-articular joint pathology to require ALL of the following criteria rather than ONE.

Note added to ACL tear section to reference Bioengineered Skin and Soft Tissue Substitutes policy for BEAR implant.

Removed CPT code 29870 and replaced a related intra-articular hyaluronan injections policy with 2.01.534; minor formatting corrections made throughout the policy.

19+policy applies to adults aged

8 weeksconservative care trial required for meniscal/other indications

2 weeks

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

conservative care trial required for ACL repair

12 monthsimaging must be within prior

does not applyMedicare Advantage applicability

Coverage Criteria for Knee Arthroscopy in Adults (19+)

Meniscal tear

Covered when ALL of the following are met:

Meniscal tear criteria: Clinical documentation confirms ONE of: positive McMurray OR positive Apley OR joint line tenderness with palpation OR diagnostic imaging (MRI, CT, etc.) within 12 months demonstrates a torn or displaced meniscus (e.g., bucket handle, radial, posterior horn) OR meniscal tear coincident with ACL injury discovered during arthroscopy; AND Repair is indicated by ONE of: functional impairment (e.g., knee locking, giving way, or decreased range of motion) OR a medically necessary ACL repair/reconstruction has been approved OR symptoms have not responded to 8 weeks of conservative care (e.g., PT, activity modification, oral analgesics); AND If age 50 or older, imaging within 12 months prior to surgery shows absence of severe knee osteoarthritis (e.g., large osteophytes, marked joint-space narrowing, severe sclerosis, Outerbridge grade 4).

Anterior cruciate ligament (ACL) tear

Covered when ALL of the following are met:

ACL tear criteria: Clinical documentation confirms ONE of: positive anterior drawer OR positive pivot shift OR positive Lachman OR diagnostic imaging (MRI, CT, etc.) within 12 months demonstrates an ACL tear; AND Repair is indicated by ONE of: symptoms have not responded to 2 weeks of conservative care (e.g., PT, activity modification, oral analgesics) OR ACL tear occurred in conjunction with meniscal tear or other multi-ligamentous knee injuries (e.g., MCL, PCL, lateral collateral, posterolateral corner) OR individual is involved in a physically demanding occupation OR individual participates in cutting/jumping/pivoting activities (e.g., skiing, basketball, football).2 weeks where specified

Posterior cruciate ligament (PCL) tear

Covered when ALL of the following are met:

PCL tear criteria: Evidence of torn PCL with ONE of: positive posterior drawer OR positive reversed pivot shift OR positive posterior sag OR diagnostic imaging (MRI, CT, etc.) within 12 months demonstrates a PCL tear; AND PCL tear occurred in combination with ONE of: injury to the posterolateral corner, medial collateral ligament tear, ACL tear, or associated avulsion fracture (e.g., Segond fracture).12 months imaging window

Arthroscopic debridement, drainage, or lavage

Covered when ONE of the following is present:

Debridement/drainage/lavage indications: Septic joint or osteomyelitis; OR septic prosthetic joint; OR postoperative arthrofibrosis (e.g., after ACL repair or total knee arthroplasty) as indicated by BOTH loss of range of motion AND symptoms that have not responded to 8 weeks of conservative care.8 weeks for arthrofibrosis

Intra-articular joint pathology

Covered when ALL of the following are present:

Intra-articular pathology: Mechanical symptoms (including locked knee, catching, or giving way) AND either imaging (radiographs or MRI) demonstrates a loose or foreign body (including hardware) OR chronic knee pain, effusion, or instability with ALL of: etiology unknown AND imaging nondiagnostic AND symptoms have not responded to 8 weeks of conservative care (e.g., PT, activity modification, oral analgesics).8 weeks for chronic nondiagnostic cases

Osteochondral defect

Covered when ALL of the following are met:

Osteochondral defect: History/exam demonstrates a displaced osteochondral lesion or presence of a loose body AND diagnostic imaging (MRI, CT, or plain x-rays) within 12 months prior to surgery shows an osteochondral defect.12 months imaging window

Chondromalacia patellae (patellar compression syndrome)

Covered when ONE of the following is present:

Chondromalacia criteria: Positive patella glide test OR positive patella tilt test; OR articular cartilage lesion with ALL of: symptoms attributed to chondral injury AND diagnostic imaging (MRI, CT, or plain x-rays) within 12 months demonstrates a cartilage defect AND symptoms have not responded to 8 weeks of conservative care (e.g., PT, activity modification, oral analgesics).8 weeks for imaging-confirmed lesions

Medical necessity criteria for knee arthroscopy and specific procedures

Covered when specified combinations of exam, imaging, and conservative therapy criteria are met:

General prerequisite: Supporting documentation must include confirming exam findings or diagnostic imaging within 12 months prior to surgery and, where required by indication, evidence of failed conservative therapy for the specified duration.

Imaging reports should be copies of radiologist reports performed within 12 months.

Conservative therapy trial: Failed trial of nonoperative conservative therapy when specified: 2 weeks for certain indications (e.g., some ACL presentations) OR 8 weeks for meniscal and other intra-articular indications and for chronic nondiagnostic presentations; conservative therapy examples include structured physical therapy, activity modification, oral analgesics.2 weeks or 8 weeks as specified

Failure to document these trials may trigger denial.

PCL-specific requirement: For PCL tear, documentation must include confirming exam (positive posterior drawer, reversed pivot shift, or posterior sag) OR diagnostic imaging within 12 months, AND evidence the PCL tear occurred with concomitant injury (e.g., posterolateral corner, MCL, ACL, avulsion fracture).

Evidence-based coverage considerations

Evidence summary relevant to arthroscopy for osteoarthritis and degenerative meniscal disease:

Arthroscopic debridement/lavage for knee OA: Randomized controlled trials (e.g., Moseley et al., Kirkley et al.) and Cochrane/systematic reviews found no benefit of arthroscopic debridement or lavage over placebo or optimized nonoperative therapy for knee osteoarthritis; joint lavage/debridement does not result in consistent pain or function benefit.

References include Moseley 2002, Kirkley 2008, Cochrane reviews.

Arthroscopy for degenerative meniscal tear in middle-aged/older patients: Trials (e.g., Katz et al.) and meta-analyses (Thorlund et al.) show no significant long-term functional advantage of arthroscopic partial meniscectomy over structured physical therapy for meniscal tears with concomitant mild-to-moderate OA; small transient pain benefit may be present at 3–6 months but not at 1–2 years.

Katz et al. 2013; Thorlund et al. 2015.

Harms and risks: Arthroscopic procedures are associated with harms including symptomatic deep venous thrombosis, pulmonary embolism, infection, and rare death; pooled harms reported (e.g., 4.13 symptomatic DVT events per 1000 procedures in meta-analysis).

Situations supporting arthroscopic intervention

Clinical situations described as appropriate for arthroscopic or surgical intervention:

Juvenile osteochondritis dissecans (JOCD): Unstable JOCD lesions or stable lesions that fail an initial course of nonoperative therapy should be considered for surgical treatment; MRI is used to assess lesion stability.

Clinical and imaging criteria guide operative decision-making.

Meniscal tears: Symptomatic meniscal tears not amenable to repair may undergo partial meniscectomy; meniscal repair is preferred in younger individuals with reparable tear patterns and requires post-operative rehabilitation and protected weight bearing.

Patient age, tear pattern, and reparability inform choice of repair vs meniscectomy.

Symptomatic synovial or cystic lesions: Symptomatic popliteal (Baker) cysts, meniscal cysts, proximal tibiofibular joint cysts, and cruciate ligament ganglion cysts producing pain or limited motion may be managed with arthroscopic excision, decompression, or excision as appropriate.

Indication depends on symptomatology and etiology.

Guideline and CMS coverage positions

Guideline and coverage positions relevant to arthroscopic procedures and intra-articular injections:

AAOS Recommendation on needle lavage: Do not suggest needle lavage for patients with symptomatic osteoarthritis of the knee (AAOS Recommendation 11; Strength: Moderate).

AAOS Recommendation on arthroscopy for OA: Do not perform arthroscopy with lavage and/or debridement in patients with a primary diagnosis of symptomatic osteoarthritis of the knee (AAOS Recommendation 12; Strength: Strong).

AAOS stance on partial meniscectomy with OA: Evidence is inconclusive to recommend for or against arthroscopic partial meniscectomy in patients with osteoarthritis and torn meniscus (AAOS Recommendation 13).

NICE NG226 (2022): Do not offer intra-articular hyaluronan injections for OA; consider intra-articular corticosteroid injections for short-term relief (2–10 weeks) when other pharmacologic treatments are ineffective or unsuitable.

Knee arthroscopic partial meniscectomy for degenerative meniscal tear(s) (for example, horizontal cleavage tear on imaging) with no associated mechanical symptoms (such as locking, giving way, or decreased range of motion) is considered not medically necessary. This exclusion reflects the policy intent and the clarifying language that imaging in older individuals must demonstrate an absence of severe osteoarthritis when surgery is considered.

There is a documented lack of scientific evidence supporting arthroscopic surgery for meniscal tears in middle-aged individuals (aged 50+). Randomized trials and systematic reviews find little or no durable benefit of arthroscopic partial meniscectomy over structured nonoperative care, with any small pain improvement limited to the short term and absent at one to two years.

Arthroscopic lavage and debridement for undifferentiated degenerative osteoarthritis is not supported by high-quality evidence. Placebo-controlled and randomized trials (e.g., Moseley and Kirkley) and subsequent systematic reviews and Cochrane analyses conclude that lavage/debridement provides no consistent benefit over optimized nonoperative therapy or placebo.

CMS has determined that certain arthroscopic procedures are not reasonable or necessary for treatment of the osteoarthritic knee, specifically: arthroscopic lavage used alone; arthroscopic debridement for osteoarthritic patients presenting with knee pain only; and arthroscopic debridement and lavage for patients with severe osteoarthritis.

This medical policy is a guide for coverage determinations but does not apply to Medicare Advantage. Providers and members should consult the applicable member benefit booklet or customer service for specific plan coverage.

Elective surgical procedures, including knee arthroscopy, will be reviewed for medical necessity and site-of-service. When site-of-service criteria are not met (for example, inappropriate use of a hospital outpatient setting when an Ambulatory Surgery Center is the appropriate site), the procedure may be considered not medically necessary for purposes of coverage review.

Arthroscopic debridement or lavage performed solely for treatment of degenerative knee osteoarthritis without a discrete mechanical lesion is not supported by randomized trials and systematic reviews and therefore is considered unsupported as a routine indication for arthroscopy.

The American Academy of Orthopaedic Surgeons issues a strong recommendation against performing arthroscopy with lavage and/or debridement in patients whose primary diagnosis is symptomatic osteoarthritis of the knee.

Rheumatoid arthritis has been removed from the list of conditions for which arthroscopic debridement, drainage, or lavage is considered medically necessary in the most recent policy update.

Procedure and Coding References

Covered CPT Codes (arthroscopy group 1)CPTCovered

29871	Arthroscopy, knee, surgical; for infection, lavage and drainage.
29873	Arthroscopy, knee, surgical; with lateral release.
29874	Arthroscopy, knee, surgical; for removal of loose body or foreign body, (e.g., osteochondritis dissecans fragmentation, chondral fragmentation).
29875	Arthroscopy, knee, surgical; synovectomy, limited (e.g., plica or shelf resection).
29876	Arthroscopy, knee, surgical; synovectomy, major, 2 or more compartments (e.g., medial or lateral).
29877	Arthroscopy, knee, surgical; debridement/shaving of articular cartilage (chondroplasty).
29879	Arthroscopy, knee, surgical; abrasion arthroplasty (includes chondroplasty where necessary) or multiple drilling or microfracture.
29880	Arthroscopy, knee, surgical; with meniscectomy (medial AND lateral, including any meniscal shaving) including debridement/shaving of articular cartilage (chondroplasty), same or separate compartment(s), when performed.
29881	Arthroscopy, knee, surgical; with meniscectomy (medial OR lateral, including any meniscal shaving) including debridement/shaving of articular cartilage (chondroplasty), same or separate compartment(s), when performed.
29882	Arthroscopy, knee, surgical; with meniscus repair (medial OR lateral).

1–10 of 12

1/2

Covered CPT Codes (ACL/PCL reconstruction)CPTCovered

29888	Arthroscopically aided anterior cruciate ligament repair/augmentation or reconstruction.
29889	Arthroscopically aided posterior cruciate ligament repair/augmentation or reconstruction.

Coding references / updatesCPT

29870

Arthroscopy, knee, diagnostic; removed from policy (coding update 04/01/26).

Coding updatesCPT

29870

Removed from coding list (previously included CPT code).

inv-25: ASA classification / clinical risk thresholds

ASA classificationExamples include American Society of Anesthesiologists (ASA) classification III or higher as an anesthesia-related increased risk for complications.

Pulmonary risk thresholdFEV1 < 50% (chronic COPD) or poorly controlled asthma with FEV1 < 80% despite treatment; moderate-to-severe obstructive sleep apnea noted as risk.

Liver risk (MELD)Advanced liver disease with MELD score > 8 is listed as increased perioperative risk.

Body mass index (BMI)Morbid obesity defined as BMI ≥ 50 is listed as an increased risk factor.

Other clinical risksEnd-stage renal disease on dialysis, bleeding disorder requiring replacement products, pregnancy, anticipated need for transfusion, or recent major cardiac/cerebrovascular events are additional risk thresholds to consider.

Provider Actions, Documentation & Prior Authorization

Denial Risk

Medical necessity and site‑of‑service review

Elective knee arthroscopy procedures will be reviewed for medical necessity and site-of-service. Procedures performed at a site that does not meet the policy's medically necessary site‑of‑service criteria (for example, inappropriate use of hospital outpatient department when an ambulatory surgical center [ASC] is the preferred site) may be denied. Providers must confirm the chosen site meets the Site of Service criteria in this policy or related ASC site‑of‑service guidance.

Site‑of‑service review applies to ambulatory surgical center (preferred), off‑campus outpatient hospital/medical center, on‑campus outpatient hospital/medical center, and inpatient hospital/medical center.
Exceptions for hospital outpatient use include no geographically accessible ASC within 30 miles with necessary equipment or physician privileges, patient age ≤18, concomitant procedures requiring hospital setting, or increased clinical risk (e.g., ASA III+, recent MI, uncompensated heart failure).

Prior Authorization

Prior authorization required

Background and Rationale

Knee pain has many causes including ligament injuries and meniscal tears. Knee arthroscopy is a minimally invasive surgical technique that permits direct visualization of intra-articular structures and allows repair or removal of damaged tissue via small incisions and specialized instrumentation.

Definitions and Clinical Terms

inv-51: Mechanical symptoms

DefinitionMechanical symptoms include locked knee, catching, or giving way and may indicate intra-articular pathology that supports consideration of arthroscopy.

Clinical relevancePresence of mechanical symptoms is a required element in the policy's intra-articular joint pathology criteria when imaging shows a loose or foreign body.

Documentation guidanceClinical history and exam should describe the specific mechanical symptom(s) (e.g., locking, catching, giving way) to support medical necessity.

inv-52: Severe osteoarthritis

Radiographic severity examplesSevere osteoarthritis referenced in the policy includes imaging findings such as Kellgren-Lawrence grade 3 or 4 or Outerbridge grade 4.

Age-related condition

Policy Revision History

2026-04-01coding_updateLatest

Coding update removed CPT code 29870 and replaced related policy reference with 2.01.534 (Intra‑Articular Hyaluronan Injections for Osteoarthritis); minor formatting corrections made.

2025-12-01annual_review

Annual review approved November 11, 2025: clarified meniscal tear imaging requirement for individuals aged 50+; removed rheumatoid arthritis as a condition supporting arthroscopic debridement/drainage/lavage and removed criteria for arthroscopic excision of popliteal cyst.

2025-11-07policy_update

Policy Summary

PayerPremera Bluecross

PolicyKnee Arthroscopy in Adults

Policy CodePolicy 7.01.549

Change TypeCriteria revisionscoding updates

Effective DateDec. 1, 2025

Next Review DateN/A

Key ActionObtain and document diagnostic imaging within 12 months and evidence of failed conservative therapy for the required duration before requesting authorization.

SourceLink

On This Page

12 months imaging window

Both exam/imaging and concomitant injury required.

Debridement/lavage contextual indications: Septic joint/osteomyelitis, septic prosthetic joint, or postoperative arthrofibrosis after ACL repair or TKA with loss of ROM and failure of 8 weeks conservative care.8 weeks for arthrofibrosis

One of these conditions required for debridement/lavage to be considered medically necessary.

Imaging and documentation expectations: Clinical documentation should describe lesion characteristics (size, location, stability), mechanical symptoms, prior conservative care and response, and include imaging reports (MRI, x-ray) performed and read within 12 months prior to surgery.12 months imaging window

Essential for cartilage and osteochondral procedures.

Thorlund et al. harms data.

Intra-articular plica: Symptomatic synovial plica that fails conservative therapy (physiotherapy, activity modification, injections) may be treated with arthroscopic excision of the entire plica.

Conservative care should be attempted first.

CMS NCD 150.9: CMS considers arthroscopic lavage alone, arthroscopic debridement for osteoarthritic patients presenting with knee pain only, and arthroscopic debridement and lavage for severe OA (Outerbridge grades III–IV) as not reasonable or necessary (not covered).

inv-26: Imaging window for PCL

Imaging time windowDiagnostic imaging (MRI, CT, or plain x-rays) demonstrating a PCL tear must be performed and reported within 12 months prior to surgery.

Supporting exam alternativeA confirming physical exam (positive posterior drawer, reversed pivot shift, or posterior sag) may substitute when documented along with imaging/clinical context.

Concomitant injury documentationDocumentation should note associated injuries (e.g., posterolateral corner, MCL, ACL) when present, as required by PCL criteria.

inv-27: Conservative therapy duration

Short trial requirement (selected indications)A failed trial of nonoperative conservative therapy for 2 weeks (e.g., physical therapy, activity modification, oral analgesics) is required for certain indications such as some ACL-related scenarios.

Standard conservative durationA trial of conservative therapy for 8 weeks (e.g., PT, activity modification, oral analgesics) is required for many intra-articular pathologies and for meniscal indications when specified.

Postoperative arthrofibrosisPostoperative arthrofibrosis after ACL repair or total knee arthroplasty requires loss of range of motion and failure to respond to 8 weeks of conservative care before arthroscopy is considered.

Chronic nondiagnostic casesChronic knee pain, effusion, or instability with nondiagnostic imaging requires 8 weeks of nonoperative conservative therapy before arthroscopy is considered.

Prior authorization is required for the knee arthroscopy CPT codes listed in the policy coding section. Requests must include the supporting clinical documentation described in the policy to justify medical necessity.

See Coding section for applicable CPT codes (e.g., 29871, 29873‑29876, 29877, 29879‑29884, 29888‑29889) and any recent coding updates.
CPT 29870 was previously noted in history and later removed; verify current accepted codes in the Coding section before submission.

Prior Authorization

Prior authorization rationale for arthroscopy

Procedures such as arthroscopic lavage/debridement for osteoarthritis or degenerative meniscal disease must be clearly justified. Documentation should demonstrate specific indications (e.g., displaced loose body, mechanical symptoms, infection) and failure of appropriate conservative care when required. Routine lavage/debridement for osteoarthritic pain without these findings is at high risk for denial.

Arthroscopic lavage or debridement for osteoarthritis alone has not demonstrated benefit over optimized nonoperative therapy and may be non‑covered per CMS and the evidence summaries.
When arthroscopy is requested for degenerative meniscal disease or osteoarthritis, include imaging and documentation of mechanical symptoms or a discrete lesion justifying surgery, plus documented trials of conservative care where specified.

Documentation Required

Required supporting documentation

Supporting documentation must be submitted with authorization requests. Include diagnostic imaging reports done within 12 months prior to surgery and clear clinical exam findings or history that meet the policy criteria for the requested procedure.

Copy of radiologist's report for MRI/CT/x‑ray performed within 12 months demonstrating the diagnosis (e.g., torn/displaced meniscus, osteochondral defect, loose body).
Clinical exam findings: positive McMurray/Apley/joint‑line tenderness for meniscal tear; positive Lachman/pivot shift/anterior drawer for ACL tear; positive posterior drawer/reversed pivot shift for PCL tear; documented mechanical symptoms for intra‑articular pathology.
For patients ≥50 years old undergoing meniscal surgery, imaging within 12 months must show absence of severe osteoarthritis (e.g., Kellgren‑Lawrence grade 3–4 or Outerbridge grade 4).

Step Therapy

Conservative therapy and step‑care expectations

Nonoperative conservative therapy is expected prior to surgery for many indications. Document trials of appropriate conservative measures and duration of therapy per the policy criteria; lack of documented conservative care may lead to denial.

Meniscal tear: 8 weeks of conservative care (e.g., structured physical therapy, activity modification, oral analgesics) unless repair is otherwise indicated or ACL repair is approved.
ACL tear: failed trial of nonoperative care for 2 weeks unless associated injuries or high‑demand activity justify earlier surgery.
Intra‑articular joint pathology, osteochondral defect, chondromalacia, and synovial disorders: generally require 8 weeks of conservative therapy when specified.
Consider adjuncts per guidelines (e.g., NICE supports short‑term intra‑articular corticosteroid injections for OA when appropriate).

Note

Verify member benefits

Verify member benefits and coverage limitations prior to scheduling. This medical policy is a guide and does not override specific member contract terms; coverage may vary and Medicare Advantage rules differ.

Always consult the member benefit booklet or contact customer service to determine plan‑specific coverage and any limits.
This policy does not apply to Medicare Advantage; CMS non‑coverage determinations (e.g., arthroscopic lavage alone for OA) may affect coverage for Medicare members.

For individuals age 50 and older, meniscal surgery requires imaging within 12 months showing absence of severe osteoarthritis (i.e., not KL grade 3–4 or Outerbridge grade 4).

Kellgren-Lawrence referenceKellgren-Lawrence grading ranges from Grade 1 (doubtful) to Grade 4 (large osteophytes, marked joint space narrowing, severe sclerosis and deformity).

inv-53: Microfracture

Procedure descriptionMicrofracture is a surgical technique to repair damaged articular cartilage by creating small holes in the subchondral bone to allow marrow-derived stem cells to stimulate cartilage repair.

Typical indication/efficacyMicrofracture is most effective for small focal defects (often cited as <2 cm) and in younger individuals; used to treat articular cartilage lesions via arthroscopic technique.

Relation to chondroplastyMicrofracture (abrasion arthroplasty or multiple drilling) is listed among arthroscopic cartilage repair options alongside chondroplasty and other cartilage procedures.

inv-54: Lachman test

Test purposeThe Lachman test is a clinical maneuver used to diagnose anterior cruciate ligament (ACL) injuries by assessing anterior tibial displacement with the knee flexed 20–30 degrees.

How performedWith the patient supine and knee flexed 20–30 degrees, the femur is stabilized and the examiner pulls the tibia forward; a positive test shows increased anterior translation without a firm endpoint compared to the unaffected side.

Policy contextA positive Lachman is one of the acceptable confirming exam findings for ACL tear documentation in the policy's coverage criteria.

inv-55: Kellgren-Lawrence Grading Scale

Scale overviewKellgren-Lawrence grading is a radiographic scale for osteoarthritis from Grade 1 (doubtful narrowing and possible osteophytic lipping) to Grade 4 (large osteophytes, marked joint space narrowing, severe sclerosis and deformity).

Grade examplesGrade 1: doubtful narrowing; Grade 2: definite osteophytes and narrowing; Grade 3: moderate multiple osteophytes, definite narrowing and some sclerosis; Grade 4: large osteophytes and severe changes.

Use in policyPolicy uses KL grades 3–4 to define 'severe osteoarthritis' for surgical eligibility considerations in older adults.

inv-56: Kellgren-Lawrence grading scale

DefinitionKellgren-Lawrence grading is a radiographic system for osteoarthritis ranging from Grade 1 (doubtful) to Grade 4 (severe narrowing, large osteophytes, sclerosis and deformity).

Clinical applicationReferenced in policy to determine presence or absence of severe OA when evaluating meniscal surgery in patients aged 50 or older.

Corresponding policy requirementImaging within 12 months must show absence of KL grade 3 or 4 to meet meniscal surgery criteria for those ≥50.

inv-57: Modified Outerbridge Classification

PurposeThe Modified Outerbridge Classification grades articular cartilage breakdown (chondromalacia) and correlates MRI descriptions to arthroscopic grades ranging from focal hyperintensity/softening to full-thickness cartilage loss with exposed subchondral bone.

Clinical useUsed to characterize cartilage lesions and to inform treatment choices such as chondroplasty or microfracture based on defect severity.

Policy relevanceOuterbridge grade 4 is cited as an imaging criterion indicating severe cartilage loss that may preclude certain arthroscopic procedures in older adults.

inv-58: Knee arthroscopy

Procedure definitionKnee arthroscopy is a surgical procedure performed through small incisions using an arthroscope to visualize, repair, or remove damaged intra-articular knee tissue.

Common indicationsIndications include diagnostic arthroscopy, meniscectomy, loose body removal, chondroplasty, microfracture, irrigation and debridement, and ligament reconstruction.

Typical instruments/approachAn arthroscope transmits images to a monitor while small surgical instruments are introduced through separate incisions to treat pathology.

inv-59: Microfracture

Technique summaryMicrofracture is a cartilage repair technique that creates small holes in the subchondral bone to stimulate marrow-derived repair for focal cartilage defects.

Indication detailsMost effective for focal defects often <2 cm in diameter and typically in younger individuals; performed arthroscopically as an adjunct to chondroplasty techniques.

Related CPT descriptionListed in policy alongside abrasion arthroplasty/multiple drilling/microfracture as arthroscopic cartilage repair options (e.g., CPT 29879).

inv-60: Arthroscopic debridement/lavage

Procedure descriptionArthroscopic debridement with lavage involves arthroscopic washout and removal of degenerative tissue from the knee joint.

Evidence-based cautionRandomized trials and systematic reviews (e.g., Moseley, Kirkley, Cochrane) found no consistent long-term benefit of lavage/debridement for osteoarthritis compared with placebo or optimized nonoperative therapy.

Policy implicationBecause evidence does not support routine benefit for degenerative OA, debridement/lavage performed solely for degenerative OA without discrete mechanical indications is considered unsupported by the policy.

inv-61: Needle lavage

DefinitionNeedle lavage is a percutaneous washout of the knee joint using needle aspiration and irrigation rather than formal arthroscopic lavage.

Guideline recommendationAAOS Recommendation 11 states needle lavage is not suggested for patients with symptomatic knee osteoarthritis (moderate strength).

Contrast with arthroscopyNeedle lavage is distinct from arthroscopic lavage/debridement; both lack evidence of benefit for primary symptomatic OA per guideline and trials cited in the policy.

Effective November 7, 2025 (following provider notification): added Site of Service Ambulatory Service Center (ASC) Select Surgical Procedures related policy and ASC criteria; related policy list updates made.

2025-04-01interim_review

Interim review approved March 10, 2025: added note in ACL section referencing Bioengineered Skin and Soft Tissue Substitutes policy for BEAR implant; related policy linkage later updated.

2023-03-01interim_review

Interim review approved February 14, 2023: corrected intra‑articular joint pathology criteria to require ALL of the listed criteria (rather than ONE) and made minor edits for standardization.

2016-05-19coding_update

Coding update added CPT code 29889 (policy history shows prior addition of ACL/PCL‑related codes and other clarifications in 2016).