HCPCS Code L1710: Legg Perthes orthosis billing guide

Key takeaways

HCPCS Code L1710 is a Legg perthes orthosis, Newington type, custom fabricated. That is the complete official CMS descriptor.

Custom fabricated is part of the descriptor, so the record must justify why a prefabricated hip abduction orthosis would not meet the need.

L1710 is a permanent national DMEPOS code on the CMS Master List, requiring a written order and proof of delivery before claim submission.

The KX modifier is required when documentation on file supports medical necessity. GY applies when Medicare statutorily excludes the item.

Practice management software like Pabau keeps the written order, fitting notes and delivery proof on one patient record.

HCPCS Code L1710 covers a Legg perthes orthosis, (Newington type), custom fabricated. That wording is the complete CMS descriptor, and nothing in it mentions a thigh lacer or a fitting allowance. Orthotic suppliers bill L1710 when they build and deliver this bilateral hip abduction device for a child with Legg-Calvé-Perthes disease.

This guide covers the descriptor, Medicare reimbursement, documentation requirements, modifier usage, and the full L1700-L1755 Legg Perthes range. It also pairs L1710 with the ICD-10-CM diagnosis codes that support medical necessity on these claims.

HCPCS Code L1710: Official description and key details

L1710 is a permanent national HCPCS Level II code in the DMEPOS category, which covers durable medical equipment, prosthetics, orthotics and supplies.

CMS publishes the descriptor as Legg perthes orthosis, (Newington type), custom fabricated, with no additional wording. The code also appears on the CMS Master List of items potentially subject to conditions of payment.

The Newington orthosis is a bilateral hip abduction device used to manage Legg-Calvé-Perthes disease. That childhood hip condition involves avascular necrosis of the femoral head, and containment orthoses hold the femoral head seated in the acetabulum while it remodels. The descriptor names the design and the fabrication method, and nothing more.

What custom fabricated means for L1710

Custom fabricated means the orthosis is built from raw materials for one named patient. It is shaped over a model or a set of measurements taken from that patient.

It is a different fabrication level from a prefabricated device, which is made in advance and then fitted. Every code in the L1700-L1755 range is custom fabricated, so fabrication level never separates one code in this family from another.

That has a practical effect on your claim file. The clinical record has to show why a prefabricated hip abduction orthosis would not have met this patient’s need. A diagnosis alone does not carry that argument. Ask the prescriber to document the anatomy, the containment required, and the reason a stock device was ruled out.

Note also what the descriptor leaves out. It says nothing about fitting or adjustments, unlike nearby prefabricated codes such as L1690, whose descriptor states “includes fitting and adjustment”. So do not assume later adjustment work is bundled into L1710 by the descriptor.

Check how your Medicare Administrative Contractor (MAC) treats adjustment and repair of a custom fabricated orthosis before you bill it.

Medicare reimbursement rates and fee schedule

Medicare reimbursement for HCPCS Code L1710 is governed by the CMS DMEPOS fee schedule, which is updated annually. Rates are expressed as national limitation amounts and may vary by MAC jurisdiction and geographic adjustment factors.

Verify the current-year rate in the CMS DMEPOS fee schedule files, or in your DME MAC’s own pricing lookup, before you submit. Figures published by third-party aggregators may not reflect the current data.

Because L1710 reimbursement involves geographic pricing adjustments, a supplier in one MAC jurisdiction may receive a different payment than a supplier in another. The national limitation amount sets the ceiling. Your MAC may pay at or below that figure, depending on locality modifiers and competitive bidding status.

Medicaid matters more here than it does for most DMEPOS codes. Legg-Calvé-Perthes disease presents in childhood. So a large share of L1710 claims go to a state Medicaid program rather than to Medicare. Pull your state’s orthotic and prosthetic fee schedule, and check its prior authorization rules before you fabricate.

Medical necessity and documentation requirements for L1710

L1710 appears on the CMS DMEPOS Master List of items potentially subject to conditions of payment. That classification means a supplier has to meet specific pre-delivery requirements before submitting a claim. Non-compliance does not just cause a denial. It can also trigger a post-payment recoupment audit.

Required documentation to support an L1710 claim includes:

• Written order: A detailed written order from the treating physician, obtained before delivery of the orthosis. This must include the diagnosis, description of the item, and the physician’s signature.
• Proof of delivery: Documented evidence that the device was received by the beneficiary, including date of delivery and beneficiary or caregiver signature.
• Medical necessity documentation: Clinical notes supporting the diagnosis of Legg-Calvé-Perthes disease or a related condition. Include imaging findings and the physician’s assessment of the need for a containment orthosis.
• Custom fabrication rationale: The prescriber’s reasoning for a custom fabricated device rather than a prefabricated one. It should tie back to the patient’s documented anatomy and containment needs.
• Fabrication and fitting records: The model or measurements the orthosis was built from, plus the fitting date. Record any later adjustments, each with its own date.
• Eligibility verification: Confirm Medicare Part B or Medicaid coverage, and check any secondary payer coordination before delivery.

Verify eligibility before the fitting appointment, not after it. Pediatric DMEPOS coverage limits and prior authorization rules vary by payer. A custom fabricated orthosis is built for one named patient, so it cannot be redirected if coverage falls through.

Medical necessity is determined by the treating physician, not the supplier. Do not assume that a confirmed diagnosis of Legg-Calvé-Perthes disease automatically establishes medical necessity for L1710. The clinical record must specifically support the need for this type of orthosis and document the expected therapeutic benefit.

Modifier requirements when billing L1710

Modifier selection for HCPCS Code L1710 directly affects claim processing outcomes. MAC guidance identifies several modifiers that apply to custom fabricated orthotic codes in this range. Incorrect modifier assignment is a leading cause of L1710 denial, and it is the easiest of the common errors to prevent before submission.

The KX modifier matters most on L1710 claims billed to Medicare. Appending KX attests that the documentation in the patient’s file meets every applicable coverage criterion. Submitting without KX when that documentation exists produces an avoidable denial. Submitting KX when the documentation is incomplete is a misrepresentation.

Review your MAC’s local coverage determination (LCD) or policy article for jurisdiction-specific modifier rules. Requirements differ between Jurisdiction C, run by CGS Medicare, and the other MAC regions. Tracking which modifier drove each orthotic denial is what surfaces a pattern before it spreads across a quarter of claims.

Billing guidelines and claim submission for L1710

A clean L1710 claim follows a defined sequence from the physician order through to submission. Most DMEPOS denials on this code trace back to a step taken out of order rather than to the coding choice itself.

1. Obtain a detailed written order: Secure the physician’s order before fitting or delivering the orthosis. The order must include diagnosis, item description, and physician signature. Orders received after delivery cannot be backdated.
2. Verify medical necessity: Review the clinical record to confirm Legg-Calvé-Perthes disease documentation, imaging reports, and the physician’s rationale for a custom fabricated Newington-type orthosis.
3. Fabricate, fit and deliver the orthosis: Record the model or measurements used, document each adjustment, and record the delivery date. Keep those notes in the claim file, because the descriptor carries no fitting allowance you can point to instead.
4. Collect proof of delivery: Obtain a signed delivery receipt from the beneficiary or their caregiver. Date must match the actual delivery date.
5. Prepare the claim file: Compile the written order, clinical notes, delivery receipt, and modifier selection rationale before claim submission.
6. Submit the claim with correct modifiers: Append KX if documentation supports medical necessity. Add NU, RR, or UE as applicable based on equipment status. Submit via your MAC’s electronic claim portal.
7. Retain documentation for audit: Keep all supporting documentation on file for a minimum of seven years. L1710’s presence on the CMS Master List makes it a candidate for post-payment review.

Read that sequence as a set of dates rather than a set of tasks. The chart below shows where each record has to fall, and the single point in the run that cannot be corrected afterwards.

Every data element has to be present and accurate before an L1710 claim leaves your system. That means the correct ICD-10-CM diagnosis code, the HCPCS code, the applicable modifiers, and the beneficiary’s details. An incomplete claim delays payment and invites a request for additional documentation.

Related HCPCS codes in the Legg Perthes L1700-L1755 range

HCPCS Code L1710 sits in a five-code family covering the Legg Perthes orthoses. All five are custom fabricated, so the code you choose turns entirely on the device design the physician prescribed. Billing L1700 for a Toronto-type device when a Newington orthosis was supplied is a coding error regardless of diagnosis.

Two points about this range save time in an audit. Each of the five is a complete base code, so none of them is an addition code that has to ride alongside another. And there is no thigh lacer variant anywhere in L1700-L1755, despite descriptors circulating online that add that wording to L1710.

Thigh lacer language does exist in HCPCS, just not in this family. L4040 and L4045 cover replacement of a molded and a non-molded thigh lacer for a custom fabricated orthosis. Those are repair codes for lower-limb orthoses, and neither one describes a Legg Perthes device.

Confirm current code status and any National Correct Coding Initiative (NCCI) edits in the AAPC HCPCS code lookup or the CMS HCPCS overview.

ICD-10 diagnosis codes that support L1710 claims

The table below lists the ICD-10-CM codes most commonly paired with L1710 claims. Pairing L1710 with a code that does not reflect the documented diagnosis is a billing error, and a systematic mismatch can amount to fraud. Select the diagnosis code that most precisely matches the physician’s documented clinical findings.

ICD-10 specificity matters for DMEPOS claims. The unspecified laterality codes M91.10 and M91.20 are acceptable when the record does not say which hip is affected. Payers still prefer the most specific code available.

When bilateral involvement is documented, code each affected side separately. Then confirm whether your payer accepts bilateral orthosis billing on one claim line or requires two. Our ICD-10-CM code reference holds the individual guides for the diagnosis codes behind these claims.

Common L1710 billing errors and how to avoid them

The denials on this code cluster around a handful of repeatable mistakes. Each one is preventable at the intake or fitting stage rather than at appeal.

• Quoting a descriptor that is not the CMS descriptor: Several online references pad L1710 with wording CMS never published. Work from the CMS HCPCS file, and describe the device in your notes rather than paraphrasing a third-party listing.
• Coding the design the practice usually supplies: Match the code to the device actually prescribed and delivered, not to the range’s most familiar entry.
• Leaving custom fabrication unjustified: A Legg-Calvé-Perthes diagnosis on its own does not explain why a prefabricated orthosis was ruled out. Get that reasoning into the order or the clinical note.
• Dating the written order after the fitting: The order has to precede delivery. A late order is the single hardest L1710 problem to fix after the fact.
• Billing Medicare for a pediatric patient covered by Medicaid: Verify the payer before fabrication, since most patients for this device are children.

How Pabau keeps an L1710 claim file audit-ready

Most orthotic suppliers assemble an L1710 claim file by hand. The order sits in one inbox and the imaging report in the patient’s chart. The fitting notes are on a paper form, and the delivery receipt is in a folder. Nobody sees the whole file until a payer asks for it. That is the worst possible moment to discover the order is dated after the fitting.

Pabau, our practice management platform, keeps those pieces on one patient record instead. The written order, the clinical note justifying custom fabrication, the fitting history and the signed delivery confirmation all attach to one timeline. Every date is there to check in seconds. Our claims software for suppliers then carries the code, modifiers and diagnosis through to the claim itself.

The outcome is a file you can hand to a reviewer without rebuilding it first. Your billing team catches a missing signature or an out-of-sequence date before submission. Fewer L1710 claims come back for additional documentation, and more of them pay on the first pass.

Manage DMEPOS billing with fewer errors

Pabau helps orthotic suppliers and DMEPOS practices track documentation requirements, manage written orders, and submit claims with the correct modifier combinations, all from one platform.

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Conclusion

HCPCS Code L1710 has a short descriptor and a long list of conditions attached to it. Legg perthes orthosis, (Newington type), custom fabricated is the whole of what CMS says.

Every argument for payment therefore has to come from your documentation rather than the code wording. Get the written order dated before delivery, justify the custom fabrication, and confirm which payer covers the child in front of you.

Pabau builds those checkpoints into the workflow, so an incomplete L1710 claim stops before it reaches the payer. Book a demo to see how Pabau supports DMEPOS billing from the written order through to payment posting.

Continue your research

Need guidance on DMEPOS denial patterns? Denial management in healthcare covers strategies for identifying and resolving common claim rejection reasons across payer types.

Looking to understand the broader billing compliance picture? Medical billing compliance requirements outlines the regulatory framework DMEPOS suppliers must follow to avoid audit exposure.

Want to streamline your claim submission process? Revenue cycle management explains the end-to-end financial workflow from order intake through payment posting for healthcare suppliers.

Wondering what makes a claim pay on the first pass? What is a clean claim sets out the data elements a payer checks before it accepts a submission.

Building the paperwork behind each claim? Superbill documentation walks through the fields that carry codes, modifiers and diagnoses onto a submitted claim.

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