Donald B. Longjohn, MD

USC Ortho Surg Assoc · Los Angeles, CA 90033-5322

AAHKS member

Fellowship: Adult reconstruction — Rancho Los Amigos National Rehabilitation Center / Keck Medical Center of USC¹
In practice: About 30 years (estimated)
2024 Medicare: 46 joint replacements²
Medicare: Accepted
AAHKS: Member — directory-listed as of 2026-08-18

1 keckmedicine.org · 2026-08-28 2 CMS claims — a lower bound

What this record establishes

The authenticated AAHKS directory lists this surgeon as a member, and CMS published hip or knee replacement services under this surgeon's NPI.

What still needs verification: board certification and current all-payer annual volume. An unmet criterion is never a finding against a surgeon: CMS publishes only the Medicare half of a practice, and a credential nobody has documented is unknown, not absent.

How each fact was established

Joint-replacement fellowship verified

Adult reconstruction fellowship — Rancho Los Amigos National Rehabilitation Center / Keck Medical Center of USC. Read on the cited page.

Joint Replacement of the Hip and Knee Academic Title Assistant Professor of Clinical Orthopaedic Surgery View Research Profile Fellowship 1995 - 1996 Arthritis & Joint Replacement Rancho Los Amigo Medical Center Residency 1991 - 1995 Orthopaedic Surgery LAC + USC Medical Center Internship 1990 - 199

Review the fellowship source ↗

Years in practice

About 30 years, estimated from training dates. The estimate allows six years for residency and fellowship, which is the shortest path there is, so the real figure may be lower.

Review the experience source ↗

Joint replacement volume

46 primary hip and knee replacements were published under this NPI in 2024 Original Medicare fee-for-service claims (13 hip, 33 knee). That is a lower bound: cash and commercially insured cases are published nowhere, for anyone. Below 100, the file proves nothing about total volume, because the rest of a practice is not in it.

Medicare participation: accepts Medicare assignment

The CMS Doctors & Clinicians file reports that this clinician accepts the Medicare-approved amount as payment in full.

CMS Medicare-listed practice: USC Care Medical Group Inc · Los Angeles, CA 90033.

AAHKS membership

Listed in the authenticated AAHKS member directory as Fellow Member.

Board certification

American Board of Orthopaedic Surgery certification is not covered by the retained dataset and has not been checked.

Is this your record?

A surgeon may correct their own page. Sign in as a physician, confirm the NPI on this record, and verify with a code texted to your cell phone. You can then correct the practice, fellowship and start-year fields, or ask for the page to come down. Corrections appear here as stated by you, beside what the public sources show.

Report an error in this record

Anyone may report an error: a patient, a practice, a colleague, or the surgeon. A person reads every report and checks it against a source before anything on the page changes. You can also write to privacy@sherlockhealth.ai.

This is a documented record, not a rating or a recommendation. It carries no stars, scores, ranks or badges. Every fact names its source and the date it was read; a fact nobody has documented reads “not yet documented,” which is a gap in the record and never a finding about the surgeon. Whether a surgeon is right for you is decided in an examination, by you and them.

Sources

What this record stands on

Consolidated dataset generated 2026-08-24; CMS participation data updated July 31, 2026; each read source carries its own date above.