CJR-X: first mandatory nationwide bundle lands October 2027.

CMS proposed CJR-X inside the FY27 IPPS rule on April 10, 2026. The structure is the same as the original Comprehensive Care for Joint Replacement model that ran from 2016 to 2024, with expanded geography and tighter target prices. CJR-X is mandatory for nearly all IPPS acute care hospitals starting October 1, 2027.

Who is in: nearly all IPPS acute care hospitals doing lower extremity joint replacement.

Who is out: TEAM participants transition to CJR-X in 2031. Maryland all-payer hospitals are exempt. Critical access hospitals and rural emergency hospitals are out.

Stop-loss is 5%. That protects rural and safety-net participants from catastrophic downside.

What the 90-day episode actually covers

The episode starts at the inpatient admission for the joint replacement and runs for 90 days post-discharge. Covers all Part A and Part B related items and services. That means: the index admission, all post-acute care (SNF, IRF, HHA, outpatient PT), all related physician services, all readmissions for related conditions, all related Part B items.

The target price is set per episode using historical data plus a discount factor. If your actual episode cost is below target, you keep the difference as a reconciliation payment. If your actual episode cost is above target, you owe CMS the difference, subject to the 5% stop-loss.

The 200-case operational threshold

The model only matters operationally if you have meaningful LEJR volume. The practical threshold is around 200 LEJR cases per year. Below that, the per-episode variance is too noisy to manage well and the administrative overhead exceeds the upside.

Above 200 cases per year, the math changes. At 500 cases per year, even a modest 3-5 percent episode cost reduction is $750,000 to $1.5 million in reconciliation payments. The hospitals that managed CJR well from 2016 to 2024 documented those numbers. The hospitals that did not engage operationally with CJR lost reconciliation payments and in some cases owed back to CMS.

What you need built within 12 months

Three things, in order of operational difficulty:

• Target-price model. You need to know your historical episode cost by surgeon, by SNF partner, by post-acute pathway. This is data work, doable in 8-12 weeks if your decision support team is engaged.
• Post-acute cost-per-episode dashboard. You need real-time visibility into where post-acute spend lands by patient. SNF length of stay, HHA visit frequency, readmission rates. This is operational discipline more than technology.
• Gain-share agreement with your orthopedic surgeons. This is the political work. CMS allows physician gain-share inside the bundle. Designing that agreement, getting surgeon buy-in, and operationalizing the math takes 6 to 9 months.

If you start the gain-share conversation in Q3 2026, you have time to negotiate and sign before the October 2027 start. If you start in 2027, you are running operationally underprepared.

Why this matters beyond CJR-X

CJR-X is the second mandatory CMS model behind the Transforming Episode Accountability Model (TEAM) that went live January 1, 2026. The pattern is clear: CMS is moving from voluntary innovation models to mandatory nationwide bundles, one service line at a time. After CJR-X comes the inpatient cardiac bundle. After that, the surgical oncology bundle. The model design from CJR-X becomes the template.

The hospitals that build target-price modeling and post-acute episode management for CJR-X are building infrastructure they will reuse three or four times in the next decade.

What to watch next

The CJR-X final rule will publish in late summer 2026 alongside the FY27 IPPS final rule. CMS may modify the start date or the stop-loss threshold based on comment volume, but the structure is unlikely to move materially. The bigger watch item is the FY28 IPPS rule (April 2027), where CMS is expected to propose the next mandatory bundle (likely inpatient cardiac).