PA-COS Certification

What This Credential Actually Is

PA-COS, as used on this site, refers to the Certified Physician Assistant in Orthopaedic Surgery. The official qualification behind it is the Certificate of Added Qualifications in Orthopaedic Surgery (CAQ-OS), issued by the National Commission on Certification of Physician Assistants (NCCPA). It is not a separate initial PA certification. You earn it in addition to your PA-C, and you must keep the PA-C active for the specialty credential to remain valid.

If you are new to the terminology, our explainers on what PA-COS is and what PA-COS stands for cover the naming in more depth. The short version: the CAQ-OS signals that a PA has documented, examined competence in orthopaedic surgery beyond the general PANCE-level foundation. For PAs who spend their days in clinic, the OR, and fracture care, it is a formal way to show that experience has been tested against a national standard.

Who Can Sit for the Exam

The prerequisites are practice-based. NCCPA expects you to hold the general credential, be licensed without restriction, and demonstrate real orthopaedic exposure. The full breakdown lives in our PA-COS requirements guide, but here are the core items:

• Current PA-C status.
• Unrestricted PA licensure in a US jurisdiction or territory, or unrestricted government practice privileges. If you hold more than one license, all of them must be unrestricted.
• 4,000 hours of orthopaedic surgery specialty experience within the preceding six years.
• 75 Category I CME credits in the specialty over six years, including 25 earned in the preceding two years.
• An attestation from a specialty physician, lead/senior PA, or physician/PA postgraduate program director who knows your work.

ACLS is recommended but not mandatory. That is a useful detail, since candidates sometimes assume it is a hard gate and delay registration unnecessarily.

Practical note on the CME rule

The "25 in the last two years" clause trips up people who front-loaded their CME early in the six-year window. If most of your orthopaedic CME is older, plan to add recent credits through fracture courses, arthroplasty updates, sports medicine conferences, or other specialty-relevant Category I activities before you apply.

Fees, Registration, and the Six-Year Window

The initial CAQ-OS pathway costs $350 in total. That breaks into two parts, and understanding the split helps you budget for a retake. For a wider view, see our PA-COS certification cost breakdown.

You have six years to complete the initial requirements once you register. That is generous, but it also means the clock on your hours and CME is rolling: the 4,000-hour and 75-credit requirements look back over six years, so timing your application well can matter. A second attempt inside the window costs $250 without repeating the $100 registration. For scheduling mechanics and testing windows, check PA-COS exam dates and scheduling.

How the Exam Is Built and Delivered

The initial examination consists of 120 multiple-choice questions split into two blocks of 60 questions, each timed at 60 minutes. That is two hours of actual testing. Separately, you get a 15-minute tutorial and a 15-minute break, which do not eat into your question time.

Questions are clinical in flavor. Expect vignettes that ask you to interpret a history, exam, or imaging finding, choose the most likely diagnosis, and then pick the next step in management. The one-minute-per-item pace rewards candidates who recognize classic orthopaedic patterns quickly. If you are weighing how demanding that is, our difficulty guide discusses what makes the format challenging.

The initial exam is not the maintenance exam

You may see references to an open-reference, online maintenance option with five minutes per question. That belongs to the recertification cycle, not the initial exam. For initial qualification, expect the closed, timed, Pearson VUE format described above.

Reading the Content Blueprint

The single most useful document for your prep is NCCPA's Content Blueprint for the Orthopaedic Surgery CAQ Examination. It is undated, and NCCPA states it is based on the 2023 PA Practice Analysis. The nine Medical Content Categories below are its exact weighted domains. For a deeper domain-by-domain walk-through, see our complete guide to all 9 content areas.

The pattern is striking. Three domains (Fractures/Dislocations, Soft-Tissue Injuries and Disorders, and Joint Disorders) account for 70% of the exam. On a 120-question test, that is roughly 84 questions drawn from just those areas. The remaining six domains share the other 30%.

High-Yield Orthopaedic Topics by Domain

The blueprint gives categories, not item lists, so you must translate each category into the topics a practicing orthopaedic PA should master. The following breakdown reflects the kinds of content these categories naturally cover; treat it as a study scaffold, not an official topic list.

Task Categories: The Second Lens on Every Question

The blueprint also classifies each question by what the clinician is being asked to do. These Task Categories overlap with the content domains rather than adding to them, so a single question about a distal radius fracture belongs to one domain and one task category at the same time. Do not add these percentages to the domain table above.

The practical implication: roughly half the exam asks you either to name the diagnosis or to choose the treatment. Another 40% tests your exam skills and your ability to order and read studies. When you review a topic, rehearse it through all four lenses: What history and exam findings point to it? What imaging confirms it? What is the diagnosis when it is atypical? What is the treatment and its alternatives?

Sequencing Your Preparation Around the Blueprint

You do not need an elaborate system. What you need is a sequence that mirrors the exam's weighting and your own blind spots. Our PA-COS study guide goes deeper on technique; here is one blueprint-driven way to order the work over eight weeks.

The logic: front-load the 25% domains while your energy is highest, keep Joint Disorders and perioperative care together because the topics interlock clinically, and save the small domains for a focused pass where recognition, not depth, earns the points. Finish with timed blocks that match the real two-block structure so the pacing feels familiar. If you want a compact refresher near the end, our one-page cheat sheet is built for that.

Attestation, Practice Exams, and Sample Critiques

The experience attestation

NCCPA requires a signed attestation confirming your procedure and patient-case experience in orthopaedic surgery. The attester can be a specialty physician, a lead or senior PA, or a physician or PA postgraduate program director who is familiar with your work. The attestation is due within 90 days of your score report, so line up your attester before exam day rather than scrambling afterward. Choose someone who has directly observed your clinical and surgical work and can speak to it credibly.

NCCPA's practice exam and free critiques

NCCPA sells a separate $50 practice examination with 60 questions, 60 minutes, and 180 days of access. Be clear-eyed about what it is: it does not provide item-by-item explanations, and it does not predict whether you will pass. Treat it as a format and pacing rehearsal, not a score forecaster.

The free sample preparation questions come with critiques that do explain the reasoning. They are the best no-cost way to see how NCCPA frames an orthopaedic vignette and justifies the correct answer. Work through them actively: cover the critique, commit to an answer, then compare your reasoning to the explanation.

Keeping the Credential for Ten Years

Once earned, the CAQ-OS is valid for ten years. To keep it, you must maintain your PA-C and unrestricted licensure, earn 125 specialty Category I CME credits during the cycle, and pass a maintenance examination. The maintenance option offered online is open-reference, with 120 questions, five minutes per question, and an approximately six-week completion window. Remember that these are maintenance rules and not the initial examination rules.

If you are weighing the long-term value, the economics and career angles are covered in our pieces on whether the certification is worth it, the salary guide, and PA-COS jobs. Orthopaedic surgical groups, hospital systems with orthopaedic service lines, and sports-medicine and trauma practices are the settings where this specialty credential is most relevant, though how employers value it varies by organization.

Frequently Asked Questions