Douglas Armstrong, MD
Douglas Armstrong, MD is an Adult Reconstructive Orthopaedic Surgery Physician in Antioch, IL, registered under NPI 1467486712. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 906 WOODLAND DR, Antioch, IL 60002. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| MD433764 | PA | Adult Reconstructive Orthopaedic Surgery… primary |
| MD433764 | PA | Pediatric Orthopaedic Surgery Physician |
| 35-083386 | OH | Orthopaedic Surgery Physician |
Licences are recorded in 2 states: PA, OH. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
Licensed in 2 states
This provider holds licences in 2 states: Ohio and Pennsylvania. Multi-state licensure often means the provider works near a state border, covers more than one office, or delivers care by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.
- Licence
- MD433764
- Specialty
- Adult Reconstructive Orthopaedic…
Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.
What Adult Reconstructive Orthopaedic Surgery covers
Recognized by several state medical boards as a fellowship subspecialty program of orthopaedic surgery, adult reconstructive orthopaedic surgeons deal with reconstructive procedures such as joint arthroplasty (i.e., hip and knee), osteotomy, arthroscopy, soft-tissue reconstruction, and a variety of other adult reconstructive surgical procedures. NUCC Health Care Provider Taxonomy, code 207XS0114X
All registered taxonomy codes
This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207XS0114X | Adult Reconstructive Orthopaedic Surgery Physician Adult Reconstructive Orthopaedic Surgery | MD433764 | PA | primary |
| 207XP3100X | Pediatric Orthopaedic Surgery Physician Pediatric Orthopaedic Surgery | MD433764 | PA | |
| 207X00000X | Orthopaedic Surgery Physician | 35-083386 | OH |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1467486712 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 11, 2006 |
| Last updated | Apr 27, 2026 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | MD |
| Practice address |
906 WOODLAND DR Antioch, IL 60002 (717) 480-7441 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 4 | 6 | 7 | 4 | 8 | 6 | 7 | 1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 4 | 3 | 7 | 8 | 8 | 3 | 7 | 2 |
Sum = 68 · next multiple of 10 = 70 · check digit = 2 · actual last digit = 2
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.