Brad A. Zwahlen, MD

Medicare activity in 2024

Official CMS public-use data for Brad A. Zwahlen, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Most frequent services

1. Injection, triamcinolone acetonide, not otherwise specified, 10 mg (J3301)330 services
2. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)275 services
3. Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)178 services
4. New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)110 services
5. Aspiration and/or injection of fluid large joint using ultrasound guidance (20611)104 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

• High cholesterol70%
• Arthritis69%
• High blood pressure54%
• Osteoporosis24%
• Anxiety20%
• Depression16%

Hospitals where Brad A. Zwahlen works

Medicare's Facility Affiliation Data lists Brad A. Zwahlen at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

• Alta Bates Summit Medical CenterOakland, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050043
• Alta Bates Summit Medical Center - Alta Bates CampBerkeley, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050305

Practice locations

Addresses where Brad A. Zwahlen is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 7; the Medicare profile lists all.

• 2450 Ashby AveBerkeley, CA 94705
• 2450 Ashby Ave, Rm 5505Berkeley, CA 94705 (510) 204‑4444
• 25 Orinda Way, 100aOrinda, CA 94563
• 2999 Regent St, Suite 225Berkeley, CA 94705 (510) 704‑7760
• 2999 Regent St, Suite 301Berkeley, CA 94705 (510) 204‑8120

Group practices

Medicare enrollment lists Brad A. Zwahlen as a member of these groups (CMS data updated October 2, 2026).

• Sutter Bay Medical Foundation3,829 clinicians in the group
• California Sports and Orthopaedic8 clinicians in the group

Specialties

• Orthopedic Surgeryprimary

Find other Orthopedic Surgery doctors in California →

Other orthopedic surgeons in Berkeley

Clinicians with the same Medicare primary specialty in Berkeley, CA — not a recommendation.

• Rebecca S. Yu, MD
• Alexander A. Theologis, MD
• Amir A. Jamali, MD
• Alexander Bradley, MD
• Lamont J. Cardon, MD
• Jeffrey A. Mann, MD
• Basil Alwattar, MD
• Christopher J. Chen, MD

All orthopedic surgeons in Berkeley →

Other clinicians in Sutter Bay Medical Foundation

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

• Charles H. Feng, MD
• Anitha Gundupalli, MD
• Judy M. Cheng, MD
• Sarah A. Schaaf, MD
• Brendan Pierce, MD
• Nancy Wang, MD

Clinician information

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
6. Medicare Care Compare — official Medicare tool to look up clinicians