PT vs. PTA: Who Does What During Knee Physical Therapy?

​When you go through physical therapy after a knee injury or knee replacement surgery, you’ll meet a team of professionals who help you get back to walking, bending, and moving with confidence. Many people don’t realize that your care might come from either a physical therapist (PT) or a physical therapy assistant (PTA). Both are skilled at guiding you through your treatment, but they play different roles in your journey.

As an experienced PT myself, let me break down the differences so you understand who does what, how your co-pays work, and what rights you have in your care.

What a Physical Therapist (PT) Does in Knee Physical Therapy

A PT is the licensed professional who evaluates you when you first arrive for therapy. They review your medical history, gather a detailed report of your symptoms, and discuss your goals. Then they perform tests to measure your strength, flexibility, balance, pain, mobility, and how well your knee joint is moving. Based on this, they create a customized treatment plan.

PTs also reassess you over time to make sure your progress is on track. Depending on your setting and insurance, you may see the PT every two weeks or about once every 30 days. If you’re struggling to get the range of motion you need after a knee replacement, or if your pain is limiting your daily activities, the PT decides how to adjust your plan. Their focus is on the big picture and making sure you’re headed towards your long-term goals with your knee health.

What a Physical Therapy Assistant (PTA) Does in Knee Physical Therapy

Once your plan is in place, much of the day-to-day treatment is carried out by a PTA. PTAs are highly trained professionals, but they don’t perform initial evaluations or change your treatment plan. Instead, they focus on guiding you through exercises, stretches, and techniques that help your knee heal and progress towards the goals you set with your PT.

For example, if your plan includes strengthening exercises to support your knee joint, the PTA will coach you through every repetition, correcting your form and encouraging you when things get tough. They’re also the ones who help with hands-on techniques like stretching or mobility work to keep your knee from stiffening up.

While PTs and PTAs often work side by side, there are clear differences in their roles, training, and responsibilities. To give you a clearer picture, here’s how they compare:

Category	Physical Therapist (PT)	Physical Therapist Assistant (PTA)
Education	Doctor of Physical Therapy (DPT), 7–8 years total schooling	Associate’s degree in Physical Therapy Assisting, ~2 years
Role in Care	Performs evaluations, designs treatment plans, updates/modifies care	Carries out treatment plan, provides hands-on care, tracks progress
Decision-Making	Can diagnose movement issues, change treatment plan	Cannot diagnose or alter treatment plan
Continuing Education	Typically requires 30 CE hours every 2 years (varies by state)	CE required, but hours vary by state (generally fewer than PTs)
Supervision Requirements	May supervise multiple PTAs at once; ratios vary by state (sometimes up to 1:4)	Always works under the direction and supervision of a PT

​How Supervision Affects Care

Because PTs often supervise several PTAs at the same time, their attention may be divided between patients and administrative tasks. This can limit their one-on-one time with you. PTAs, on the other hand, typically spend more time delivering direct care, which means you may get more consistent hands-on treatment.

​Pros of Working with a PT

• Higher level of education and clinical training
• Stronger critical thinking and problem-solving abilities
• Deeper understanding of complex medical conditions and co-morbidities
• Able to evaluate and adapt your treatment plan as you progress

Pros of Working with a PTA

• More direct, hands-on time during your sessions
• Often more practiced in manual techniques because they deliver them daily
• Great at keeping you consistent and motivated through the tough parts of rehab

Schooling and Training: PT vs. PTA

It helps to understand the difference in training. PTs complete a doctoral degree in physical therapy, which usually takes seven years of combined undergraduate and graduate education. PTAs complete a two-year associate degree focused on carrying out therapy treatments under the supervision of a PT.

This doesn’t mean PTAs are less important. In fact, PTAs are often the ones you’ll spend the most time with during your physical therapy sessions. Their education ensures they know how to safely guide you through everything your PT prescribes.

Both PTs and PTAs are required by their state licensing boards to complete continuing education in order to maintain licensure and stay in good standing. For example:

• In Tennessee (where I live), both PTs and PTAs must complete 30 hours every 24 months to renew their licenses.
• In Kentucky, PTs need 30 CE hours every two years, whereas PTAs need 20 CE hours in the same period.

These regulatory requirements ensure that both physical therapists and physical therapist assistants are continuously expanding their knowledge base, staying current with clinical best practices, and reinforcing safe, effective patient care.

Who You See and Your Co-Pay

Here’s something most people don’t realize: whether you see a PT or a PTA, your co-pay is the same. Insurance doesn’t give you a discount if you see the assistant more often. That’s why it’s important to know the difference in roles and to feel comfortable with who you’re working with.

If you prefer to have a PT for certain sessions, you have the right to ask. Some people feel more confident when the PT is directly involved in their treatment, especially in the early stages after a knee replacement surgery. Others enjoy the encouragement and hands-on time they get with a PTA. You’re allowed to request either, and it’s okay to advocate for what feels right for you.

Teamwork That Benefits You

The truth is that PTs and PTAs work closely together to support you. Your PT designs the roadmap, and your PTA helps you walk it step by step. I’ve seen how effective this teamwork can be. When you’re trying to regain your strength and mobility, it helps to have both big-picture strategy and consistent support. Both PTs and PTAs bring valuable skills to the table, and when they collaborate, you benefit.

Taking Charge of Your Care

Knowing the difference between PTs and PTAs gives you power in your knee physical therapy journey. Instead of wondering who is who, you can ask questions and make informed decisions. If you’re unsure why you’re doing a particular exercise, ask your PTA. If you want to know how your therapy plan fits into your long-term goals, ask your PT. The more involved you are, the better your outcomes will be.

Your Knee, Your Choice

Physical therapy is one of the most important parts of regaining strength and mobility after an injury or knee replacement. PTs and PTAs both play essential roles in getting you there. Remember that you pay the same co-pay regardless of who you see, and you always have the right to ask for more PT involvement if that’s what you prefer.

If you’re looking for more ways to support your therapy at home, programs like GoKnee offer tools and guidance that mimic the hands of a therapist so you can perform advanced therapy techniques safely from your living room. Good luck on your knee journey!

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