Evidence basis for authorization review

Evidence reviews (rationale and literature synthesis) inform authorization decisions. The internal evidence basis includes systematic reviews, comparative cohort studies, randomized trials (including the Cartiva MOTION noninferiority RCT and a long-term RCT of arthrodesis vs arthroplasty), HTA conclusions (e.g., Hayes D2 rating for Cartiva), and device-specific series. Key findings used in reviews: arthrodesis demonstrates greater pain reduction in several studies and long-term follow-up; implants (metallic hemiarthroplasty and synthetic cartilage) show improved range of motion but variable pain outcomes and higher revision/removal rates in some series. Limitations of the evidence (heterogeneity, retrospective series, limited long-term comparative follow-up, and crossover/analysis issues in noninferiority trials) are considered when determining medical necessity and the need for prior authorization.

• Use latest literature updates through August 2025 when reviewing requests.
• Weigh RCT evidence (e.g., Baumhauer et al. 2016; Stone et al. long-term RCT) and comparative cohort data (e.g., De Bot et al. 2022) heavily in authorization decisions.

Prior authorization for MTP arthroplasty

Prior authorization is likely required for first MTP joint arthroplasty (hemiarthroplasty or synthetic cartilage implant) given variable long-term comparative effectiveness and need to document prior therapies, patient selection, and coding. Requests should be reviewed for completeness and clinical justification before approval.

• Document whether the request is for metallic hemiarthroplasty (e.g., HemiCAP, BioPro, AnaToemic, HemiEDGE, LPT) or for a synthetic cartilage implant (Cartiva).
• If implant HCPCS or CPT implant codes are billed, an authorization that links the implant device to the surgical CPT line is expected (see coding callout).

Clinical selection verification

Verify that the individual meets clinical selection consistent with trial populations and guideline-informed criteria: symptomatic advanced hallux rigidus (e.g., clinical Coughlin grade 2–4 or equivalent symptoms), persistent severe disabling symptoms despite conservative care, and absence of exclusionary deformities (large osteochondral lesions >10 mm, severe hallux valgus >20°, hallux varus). Confirm the patient’s goals (desire to preserve motion) and suitability for the specific device.

• Confirm symptom severity (e.g., VAS >40/100 used in pivotal trials).
• Document absence of exclusion criteria used in trials (lesions >10 mm, hallux varus, hallux valgus >20°).

Prior authorization likely required

Prior authorization is likely required when clinical benefit is uncertain or evidence shows limited comparative long-term benefit and potential safety signals (e.g., higher device removal or conversion rates). Cases lacking adequate prior conservative therapy, missing outcome measures, or absent documentation of informed consent regarding device risks should be escalated for peer review or denied.

• Escalate cases with inadequate documentation of prior treatments or missing PROMs.
• Peer review recommended for requests in patients with risk factors for poor outcome (high activity, severe deformity).

Coding required on authorization

When requesting authorization, report both the procedure CPT code(s) and any implant HCPCS/HCPCS II codes. Include revenue codes and ICD-10 diagnosis codes as applicable. Provide device-specific HCPCS when known (e.g., L8641, L8642) and the surgical CPT describing the procedure (e.g., CPT 28291 when applicable).

• Provide CPT procedure code(s) and link to implant HCPCS (L8641, L8642, or L8699 as applicable).
• Include place of service and anticipated Type of Service (surgical) on the request.

Revision risk noted

Revision is most frequently performed for persistent pain. Reported revision/removal rates vary by device and series: metallic hemiarthroplasty series report revisions in the low-to-mid teens percent in some series; Cartiva pivotal and follow-up data reported implant removal/conversion rates around 9–15% at midterm follow-up. Document the patient-specific estimated revision risk and prior discussions.

• Include prior joint surgeries and any prior implant procedures.
• If prior implant failure or conversion is planned, provide operative and radiographic details.

Risk from inferior long-term outcomes

Long-term outcomes may be inferior for some implants compared with arthrodesis. Randomized long-term data and cohort analyses have shown greater pain reduction and higher patient satisfaction with arthrodesis at extended follow-up; arthroplasty failures can be technically difficult to salvage. Consider this risk when authorizing motion-preserving implants.

• Document rationale for choosing implant over arthrodesis given potential for inferior long-term pain outcomes.
• If patient preference drives choice, document informed consent addressing possible inferior long-term outcomes and salvage complexity.

Evidence insufficiency risk

Evidence insufficiency for some devices (e.g., Hayes D2 assessment for Cartiva) and heterogeneity of series may warrant denial or more stringent documentation requirements. Newer or less-studied implants lacking comparative long-term data are subject to additional review.

• Requests for novel or poorly studied devices should include peer-reviewed comparative evidence and device-specific long-term safety data.
• If adequate evidence is not provided, the request may be deferred or denied pending additional data.

Higher rate of adverse outcomes and device removals/conversions reported for Cartiva versus arthrodesis

Some implants (Cartiva synthetic cartilage) have demonstrated higher rates of certain adverse outcomes and device removals/conversions in follow-up studies and case series. Authorization reviewers should consider device-specific safety signals (e.g., higher rates of walking/up-stairs/squat difficulty, higher device removal rates) when evaluating requests.

• Provide device-specific complication rates and any MAUDE or postmarket surveillance reports if available.
• Document patient counseling on expected adverse event profile and percentages for device removal/conversion.

Claims using implant HCPCS or CPT codes may be subject to coding review

Claims that include implant HCPCS or CPT implant codes may be subject to coding review if submitted without the corresponding surgical CPT line items or without prior authorization linking device and procedure. Submit complete operative coding and authorization references to avoid billing denials or coding audits.

• Ensure implant HCPCS (L8641, L8642, L8699) are accompanied by an appropriate surgical CPT on the same claim.
• Include authorization number and documented surgical indication on claim submission.

Required clinical outcome documentation

Required clinical outcome documentation on authorization requests includes preoperative and (if available) prior nonoperative outcome measures: VAS pain score, FAAM (ADL and sports) and/or AOFAS-HMI, range of motion, and specific functional limitations. Include baseline values and MCID context when possible.

• Provide baseline VAS and FAAM/AOFAS scores and prior nonoperative response.
• If previous PROMs are unavailable, include detailed clinical exam findings and pain/functional descriptors.

Suggested documentation elements

Suggested documentation elements to include with the authorization request: clinical indication and Coughlin grade (or equivalent), baseline VAS and FAAM scores, duration of symptoms, imaging reports, prior conservative therapies tried, prior foot surgeries, and surgeon’s rationale for selecting implant over cheilectomy or arthrodesis.

• Attach preoperative radiographs and imaging reports.
• List prior treatments with dates and durations (orthotics, NSAIDs, injections, activity modification, cheilectomy if performed).

Documentation of prior treatments, informed consent including device removal risk (~15% by 5 years), and follow-up outcomes

Document prior treatments and conservative care failure per policy: a reasonable trial of orthotics/modified footwear, medical therapy (NSAIDs/acetaminophen or intra-articular injections), activity modification, and debridement of hyperkeratotic lesions if present. Also document informed consent that addresses device-specific risks, including the roughly reported risk of device removal/conversion (e.g., ~15% by 5 years for some implants), and planned follow-up to monitor outcomes.

• Specify durations and responses to each conservative measure.
• Obtain and include signed informed consent that discusses potential need for device removal/conversion and long-term uncertainty.

Conservative care requirement

Conservative nonoperative therapy is required prior to considering hemiarthroplasty or synthetic cartilage implants. Document failure of a reasonable trial of conservative measures as described in policy before approving implant surgery.

• Conservative care must include orthotics/modified footwear, medical therapy (NSAIDs/acetaminophen or injections), activity modification; debridement if indicated.
• Cheilectomy or arthrodesis are established surgical alternatives and should be considered and documented as discussed with the patient.

Conservative therapy recommended first

Nonoperative care (orthotics, NSAIDs, activity modification) and established operative alternatives (cheilectomy, arthrodesis) are recommended first-line options. Hemiarthroplasty or synthetic cartilage implants are alternatives for selected patients who have failed these measures and wish to preserve joint motion.

• Document why cheilectomy or arthrodesis are unsuitable or undesired for this patient when requesting an implant.
• Consider arthrodesis as preferred option when long-term pain relief is the primary surgical goal.

Comparative evidence suggests arthrodesis outcomes are at least similar and may be superior

Comparative evidence suggests arthrodesis provides at least similar and often superior pain reduction compared with arthroplasty/implant options; arthrodesis also demonstrates comparable or lower long-term revision rates in some series. When authorizing implants, assess whether the patient’s activity demands and desire to preserve motion justify choosing an implant despite comparative data favoring arthrodesis for pain outcomes.

• If an implant is authorized, document patient selection criteria aligning with studies that showed best outcomes (lightly active, minimal valgus deformity, desire to retain dorsiflexion).
• Note that arthrodesis may be favored for patients prioritizing maximal pain relief.