L5816 Endoskeletal Polycentric Knee — Reimbursement | OpenPayer

Summary & Overview

HCPCS L5816: Endoskeletal Knee-Shin Addition, Polycentric Knee with Mechanical Lock

HCPCS Level II code L5816 designates an addition to an endoskeletal knee-shin prosthetic system: a polycentric knee with a mechanical stance phase lock. The code applies to prosthetic components used to provide enhanced stability during stance for lower-limb amputees and is relevant to prosthetists, orthotists, rehabilitation clinicians, and payers overseeing durable medical equipment coverage. Nationally, proper coding for advanced knee-shin components affects device selection, clinical outcomes, and coverage determinations for beneficiaries requiring stable gait mechanics.

Key payers addressed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise reference to the code function and clinical context, payer coverage considerations, common modifiers, and typical settings where this component is fitted. The publication also outlines benchmarking and policy-relevant points readers should review when evaluating claims for prosthetic knee-shin additions, and it highlights clinical implications for mobility and safety tied to mechanical stance-phase locking in polycentric designs.

Intended for a national audience, this summary provides clear orientation to the code, its clinical purpose, and the coverage landscape so that coding specialists and clinical teams can locate detailed billing guidance, compare payer practices, and align documentation with device function and patient needs.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicareL5816HCPCS Level IIprostheticsknee-shin systempolycentric kneemechanical stance lockdurable medical equipmentprosthetic coding

Billing Code Overview

HCPCS Level II code L5816 describes an addition to an endoskeletal knee-shin prosthetic system featuring a polycentric knee with a mechanical stance phase lock. This component is used as part of a lower-limb prosthesis intended to provide joint stability during the stance phase of gait while allowing polycentric motion during swing and other phases.

Service type: Prosthetic component — knee-shin system addition

Typical site of service: Prosthetics and orthotics clinic, outpatient rehabilitation facility, or specialty prosthetic fitting center

Clinical & Coding Specifications

Clinical Context

A 56-year-old patient with a transtibial amputation presents to a prosthetics clinic for prosthesis optimization. The treating prosthetist evaluates gait and determines the existing endoskeletal knee-shin system requires an upgrade to a polycentric mechanical knee with a stance phase lock to improve stability during weight-bearing and reduce fall risk. The clinical workflow includes: initial prosthetic evaluation, measurement and casting or digital scan of the residual limb, selection and ordering of the polycentric knee-shin addition, fabrication and bench alignment in the prosthetic lab, fitting and alignment session, gait training with a physical therapist, and follow-up adjustments. Typical site of service is an outpatient prosthetics clinic or prosthetics laboratory within a hospital outpatient department. The service is billed using L5816 for the addition of an endoskeletal polycentric knee-shin system with a mechanical stance phase lock, with usual postoperative or chronic amputee care accompanying fittings and functional training.

Coding Specifications

Modifier	Description	When to Use
`LT`	Left side (not in provided list)	Data not available in the input.
`RT`

HCPCS L6722: Heavy-Duty Mechanical Voluntary-Closing Terminal Device

HCPCS-L8721-PROSTHETIC-RECEPTOR-SOLE-REPLACEMENT

HCPCS L8721: Receptor Sole for Prosthetic Device, Replacement

HCPCS-L6975-INTERSCAPULAR-THORACIC-MYOELECTRIC-PROSTHESIS

HCPCS L6975: Interscapular-Thoracic Myoelectric Upper-Extremity Prosthesis

HCPCS-L8485-PROSTHETIC-SOCK-UPPER-LIMB-FITTING-SINGLE-PLY

HCPCS L8485: Prosthetic Sock, Single-Ply, Upper Limb Fitting

HCPCS-L5710-EXOSKELETAL-KNEE-SHIN-SINGLE-AXIS-MANUAL-LOCK

HCPCS L5710: Exoskeletal Knee-Shin System, Single-Axis Manual Lock

HCPCS-L5160-KNEE-DISARTICULATION-MOLDED-SOCKET-BENT-KNEE-SACH-FOOT

HCPCS L5160: Knee Disarticulation Molded Socket with Bent Knee and SACH Foot

HCPCS-L8511-TRACHEOESOPHAGEAL-PROSTHESIS-REPLACEMENT

HCPCS L8511: Tracheoesophageal Prosthesis Replacement

HCPCS-L8470-PROSTHETIC-SOCK-BELOW-KNEE-SINGLE-PLY

HCPCS L8470: Prosthetic Sock, Single-Ply, Below-Knee Fitting

HCPCS-L5630-SYMES-EXPANDABLE-WALL-SOCKET-LOWER-EXTREMITY

HCPCS L5630: Lower Extremity Symes Expandable Wall Socket

HCPCS-L5976-LOWER-EXTREMITY-ENERGY-STORING-FOOT

HCPCS L5976: All Lower Extremity Energy-Storing Prosthetic Foot

Showing 1–10 of 472

Taxonomy Code	Specialty	Notes
`223E00000X`	Prosthetics and Orthotics	Primary specialty providing selection, fabrication, and fitting of `L5816` components.
`208VP0000X`	Physical Medicine & Rehabilitation	Clinicians who coordinate amputee care, functional assessments, and gait training.
`208D00000X`	Physical Therapist	Provides gait training and therapeutic interventions after fitting.
`207K00000X`	Orthopedic Surgery	Surgeons who perform amputations and collaborate on prosthetic prescription and complex cases.
`3336C0001X`	Occupational Therapist	Assists with ADL training and prosthesis use in daily living contexts.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`Z44.2`	Encounter for fitting and adjustment of prosthetic device of lower limb	Directly indicates the clinical service of fitting or adjusting a lower-limb prosthesis such as a polycentric knee-shin addition.
`Z43.9`	Encounter for attention to artificial openings, unspecified	Relevant when coordinating prosthetic care in patients with complex residual limb or stoma considerations.
`Z89.419`	Acquired absence of right leg below knee	Indicates transtibial amputation status on the right; common reason for prosthetic knee-shin components.
`Z89.419`	Acquired absence of left leg below knee	(If left side) Indicates transtibial amputation status on the left; common reason for prosthetic knee-shin components.
`M24.571`	Contracture, right knee	Knee joint stiffness that may influence prosthetic selection and alignment.
`M24.572`	Contracture, left knee	Knee joint stiffness influencing prosthetic selection and alignment.
`M21.661`	Varus deformity, right knee	Limb alignment issues that affect prosthetic fitting and component selection.
`M21.662`	Varus deformity, left knee	Limb alignment issues that affect prosthetic fitting and component selection.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`97760`	Orthotic(s) management and training, initial encounter, each 15 minutes	Used for training the patient in use of the new prosthetic knee-shin system during outpatient therapy sessions.
`97761`	Prosthetic training, subsequent encounter, each 15 minutes	Billing for ongoing training and adjustments after initial fitting and gait training.
`97763`	Orthotic/prosthetic follow-up, new fitting, prosthetic training	Used for follow-up visits focused on fitting adjustments and functional training after delivery of `L5816`.
`99070`	Supplies and materials (except spectacles), provided by the physician over and above those usually included with the office visit or other services rendered	Use for miscellaneous fabrication materials or components not separately billed under `L5816` when payer allows.
`99213`	Office or other outpatient visit for the evaluation and management of an established patient, typically 15 minutes	Common E/M code used by clinicians evaluating prosthetic function and making fitting decisions; billed alongside prosthetic services according to payer rules.
`20610`	Arthrocentesis, aspiration and/or injection; major joint or bursa (e.g., shoulder, hip, knee)	Data not typically associated with this prosthetic addition; include for completeness only if concurrent joint procedures occur — otherwise not routinely related.

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