CMS mandates 5,556 specialists join new payment model January 1
The Centers for Medicare & Medicaid Services (CMS) has released the final list of 5,556 specialists required to participate in its Ambulatory Specialty Model starting January 1, 2027. This model ties a portion of Medicare Part B payments to how these specialists manage patients with heart failure or low back pain.
The list, published on CMS’s website, is 16 percent smaller than the preliminary version released in February. That earlier list included 6,637 clinicians, according to an analysis by Value-Based Care Advisors.
The final roster includes 2,215 cardiologists for heart failure and 3,341 specialists for low back pain. The latter group comprises 826 physical medicine and rehabilitation physicians, 760 orthopedic surgeons, 627 pain management physicians, 487 anesthesiologists, 395 interventional pain management physicians, and 246 neurosurgeons.
These specialists practice across 2,308 organizations in 232 metro areas spanning 46 states. Texas leads with 960 participants, followed by California with 586, Florida with 481, Georgia with 303, and New Jersey with 263. The Houston and Dallas metro areas lead all regions with 307 and 271 participants, respectively, followed by the Lakewood-New Brunswick, New Jersey, area with 241 and metro Atlanta with 208. Among organizations, Inova Health Care Services has the most participants with 37, followed by HealthTexas Provider Network with 35, OrthoLoneStar and Lehigh Valley Physician Group with 31 each, and St. Luke’s Physician Group with 30.
Small practices are well-represented, with 2,101 specialists, or 38 percent, working in these settings. This share rises to 42 percent for low back pain specialists and 65 percent for interventional pain management physicians, compared with 31 percent in the heart failure cohort. Geography also plays a role: most participants in Florida (61 percent), California (55 percent), and Texas (51 percent) work in small practices, while only 9 percent in Washington and 12 percent in Ohio and Indiana do.
Performance Metrics and Payment Adjustments
The model evaluates participants on quality, cost, improvement activities, and interoperability, using a framework based on MIPS Value Pathways. Performance determines adjustments to future Part B claims, ranging from -9 percent to +9 percent in the first two years, expanding to ±12 percent by the final year.
These adjustments apply to all Part B professional services, not just those related to heart failure or low back pain. This broad scope has raised concerns, as noted by the American College of Surgeons.
Specialists were selected based on their attribution to at least 20 episodes of heart failure or low back pain annually and their practice location within the model’s mandatory geographic areas, which cover roughly one-quarter of metro areas nationwide.
The model’s performance years run through 2031, with payment adjustments applied from 2029 to 2033. Care provided in 2027 will impact payments in 2029.
Anders Gilberg, senior vice president of government affairs at MGMA, expressed concerns about practice readiness. In a September 14 interview, he stated, “The bottom line is they're not ready because they don't know.”
Practices should verify their physicians’ inclusion by searching the dataset using NPIs. The final list is based on 2025 data, while the preliminary list used 2024 claims. The file also lists 23 NPIs more than once, in some cases under different metro areas, so practices should confirm how each physician is recorded.
Potential changes to the model are still under consideration. CMS proposed modifications in the CY 2027 Physician Fee Schedule, with the comment period closing on September 14. Gilberg said MGMA expects the final rule on or about November 1, which “gives a short period of time for practices to prepare” before the first performance year opens January 1.
