Report Highlights

U.S. Knee Replacement Market: Market Overview

The United States holds the world's largest knee replacement market, with more than 700,000 primary total knee arthroplasties performed each year. Implant and instrument revenue reached an estimated USD 6.8 billion in 2024 and is concentrated among five manufacturers. Private industry has led product innovation, from cruciate-retaining designs to robotic-compatible implant families, while government has set the economics through Medicare reimbursement. Procedure volume is shaped by ageing demographics and by CMS payment rules that determine whether a surgery is billed as inpatient or outpatient.

Government's influence is most direct in Medicare, which funds the majority of primary knee replacements for patients aged 65 and over and sets payment rules through the Inpatient Prospective Payment System and the Ambulatory Surgical Center payment system. Private leadership is visible in robotic navigation, where Stryker's Mako and Zimmer Biomet's ROSA have built installed bases across large U.S. hospital systems. Policy therefore determines where and how much surgery is reimbursed, while manufacturers compete on implant design within those limits.

Policy-Driven Growth in U.S. Knee Replacement

The clearest demand lever is the Centers for Medicare & Medicaid Services' decision to add total knee arthroplasty to the Ambulatory Surgical Center Covered Procedures List in the CY2020 Outpatient Prospective Payment System and ASC final rule. This let eligible Medicare beneficiaries receive the operation in lower-cost facilities, expanding volume without adding hospital bed days. Surgeons responded by moving same-day discharge cases into ASCs, where facility payments run well below hospital outpatient rates.

Mandatory bundled payments add a second mechanism. CMS finalised CJR-X in the FY2026 Inpatient Prospective Payment System final rule, extending the Comprehensive Care for Joint Replacement model to additional metropolitan statistical areas from October 2025, with episodes priced against MS-DRG 469 and 470 spending. Hospitals exceeding target prices repay Medicare, which forces implant standardisation and pushes patients toward outpatient pathways. The Ambulatory Specialty Model, finalised in the CY2026 Physician Fee Schedule and effective 1 January 2027, applies similar episode accountability to outpatient knee procedures.

Regulatory Barriers and Compliance Costs in U.S. Knee Replacement

Device clearance is the first barrier. The FDA's Center for Devices and Radiological Health reviews knee implants under Section 510(k) of the Federal Food, Drug, and Cosmetic Act, with a MDUFA performance goal of 90 FDA days for predicate-based devices, while novel designs require premarket approval with a 180-day FDA review goal. Manufacturers must also meet the Quality Management System Regulation under 21 CFR Part 820, which takes effect 2 February 2026 and aligns with ISO 13485, adding documentation costs for every implant family.

Payment and conduct rules impose the second layer of cost. The Anti-Kickback Statute, enforced by the HHS Office of Inspector General, constrains surgeon consulting and implant-loan arrangements, and manufacturers must report physician payments through CMS's Open Payments programme under the Physician Payments Sunshine Act. State health departments administer certificate-of-need laws requiring approval before new ASCs open in states including New York and Connecticut. A Section 232 investigation into medical devices, launched by the Department of Commerce in September 2025, could add tariffs to imported implant components.

Policy-Created Opportunities in the United States

Policy creates a clear procurement gap for ASC-specific implant systems. Because ASM and CJR-X penalise cost overruns, ASCs need compact instrument sets, pre-packaged cemented and cementless trays, and robotic platforms priced for single-room installation. Vendors that certify these configurations for ASC use will capture the volume that Medicare's outpatient migration is redirecting away from hospital operating rooms.

Remote monitoring offers a second opening. CMS remote physiologic monitoring codes, including CPT 99453 and 99454, reimburse device setup and data collection during post-operative recovery, allowing vendors to bundle connected sensors with implants inside episode contracts. Price transparency rules under 45 CFR Part 180 require hospitals to publish standard charges, creating demand for implant suppliers offering transparent per-case pricing.

Market at a Glance

Leading Market Participants

• Zimmer Biomet
• Stryker
• DePuy Synthes
• Smith+Nephew
• Exactech
• Medacta
• Corin
• restor3d
• Waldemar Link
• MicroPort Orthopedics

Regulatory and Policy Environment

The primary legislation is the Federal Food, Drug, and Cosmetic Act, as amended by the Medical Device Amendments of 1976 and the Medical Device User Fee Amendments, with MDUFA V authorised under the FDA Reauthorization Act of 2017 for fiscal years 2023 to 2027. The Food and Drug Administration administers device clearance through its Center for Devices and Radiological Health, the Centers for Medicare & Medicaid Services administers coverage and payment, and the HHS Office of Inspector General enforces fraud and abuse law. Key compliance requirements include 510(k) or PMA clearance, establishment registration, unique device identification under 21 CFR Part 830, and Open Payments reporting.

Upcoming changes are dated. The QMSR takes effect 2 February 2026, the Ambulatory Specialty Model starts 1 January 2027, and MDUFA VI must be enacted before MDUFA V authority expires on 30 September 2027. Compared with regional peers, the U.S. clears predicate-based knee implants faster than the EU Medical Device Regulation (Regulation (EU) 2017/745) requires, since notified-body certification adds months to approvals. Canada's Medical Devices Regulations (SOR/98-282) demand a device licence before sale, but provinces negotiate implant prices centrally, whereas U.S. hospitals face federal bundled-payment accountability.

Long-Term Policy Outlook for U.S. Knee Replacement

By 2032 the most consequential shift will be site-of-care alignment. CMS will extend outpatient episode accountability beyond pilot regions, converting a volume shift into a structural one. Robotic-assisted implantation will become a coverage expectation rather than a differentiator, because bundled-payment rules reward cost-efficient episodes regardless of setting.

MDUFA VI will set the review performance goals and user fees governing knee implant clearances through 2032. Section 232 tariff outcomes will raise landed costs for imported cobalt-chromium components unless manufacturers expand domestic machining, as Zimmer Biomet has done at its Warsaw, Indiana campus. Policy will determine whether projected 5.3% annual growth accrues to hospitals, ASCs, or manufacturers.