Grietje Van Dyk, MD
Grietje Van Dyk, MD is an Orthopaedic Surgery Physician in Los Alamitos, CA, registered under NPI 1003126830. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
Here is what surrounds this office in Los Alamitos, based on OpenStreetMap data collected Sep 6, 2026. Parking is available about 427 ft away. The nearest transit stop is 688 ft away, served by Katella-Bloomfield. A pharmacy sits 0.40 mi from the entrance (CVS Pharmacy), which helps if you leave with a prescription. If you arrive early, there is a coffee shop 0.28 mi away.
Getting here and what is nearby
Transit Katella-Maple 143 ft ~1 min
Parking 199 ft ~1 min
Transit Katella-Kaylor 260 ft ~1 min
Parking 255 ft ~1 min
Parking 427 ft ~2 min
Coffee Cafe Niko 533 ft ~3 min
Mo-Fr 07:00-17:00; Sa 09:00-14:00
Transit Katella-Bloomfield 688 ft ~3 min
Restaurant Pittsburgh Broasted Chicken 880 ft ~4 min
3671 Katella Avenue, Los Alamitos 90720
Restaurant McDonald's 0.27 mi ~6 min
3562 Katella Avenue, Los Alamitos 90720
06:00-22:00
Coffee Starbucks 0.28 mi ~6 min
Convenience 7-Eleven 0.37 mi ~8 min
10772 Los Alamitos Boulevard, Los Alamitos 90720
Gas station Shell 0.37 mi ~8 min
Restaurant Wahoo's Fish Taco 0.37 mi ~8 min
10931 Los Alamitos Boulevard, Los Alamitos 90720
Mo-Su 11:00-19:30
Pharmacy CVS Pharmacy 0.40 mi ~8 min
Gas station Arco 0.42 mi ~9 min
Hotel Fairfield Inn & Suites 0.44 mi ~9 min
10650 Los Alamitos Boulevard, Los Alamitos 90720
Grocery Vons 0.46 mi ~10 min
11322 Los Alamitos Boulevard, Los Alamitos 90720
Mo-Su 06:00-23:00
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| G61231 | CA | Orthopaedic Surgery Physician primary |
This provider holds licence G61231 issued in CA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
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.
What Orthopaedic Surgery covers
An orthopaedic surgeon is trained in the preservation, investigation and restoration of the form and function of the extremities, spine and associated structures by medical, surgical and physical means. An orthopaedic surgeon is involved with the care of patients whose musculoskeletal problems include congenital deformities, trauma, infections, tumors, metabolic disturbances of the musculoskeletal system, deformities, injuries and degenerative diseases of the spine, hands, feet, knee, hip, shoulder and elbow in children and adults. An orthopaedic surgeon is also concerned with primary and secondary muscular problems and the effects of central or peripheral nervous system lesions of the musculoskeletal system. NUCC Health Care Provider Taxonomy, code 207X00000X
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 | 1003126830 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Oct 14, 2010 |
| Last updated | Oct 27, 2020 |
| Status | Active |
| Sole proprietor | Yes |
| Gender | Female |
| Credential | MD |
| Practice address |
3851 KATELLA AVE STE 150 Los Alamitos, CA 90720 (562) 314-1400 Fax (562) 431-0564 |
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 | 0 | 0 | 3 | 1 | 2 | 6 | 8 | 3 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 2 | 2 | 3 | 8 | 6 |
Sum = 50 · next multiple of 10 = 50 · check digit = 0 · actual last digit = 0
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.