Patellofemoral Pain: The Importance of the Subjective Assessment

Nearly 1 in 4 people will experience Patellofemoral Pain (PFP) across their lifespan, making it one of the most common knee complaints encountered by physiotherapists.

The condition is notoriously multifactorial, with patients presenting a wide spectrum of symptoms, irritability levels, and functional limitations, which can complicate assessment and management.

The subjective assessment is the key to accurately diagnosing PFP and understanding its impact on the patient’s life. In this blog, we’ll share some important lessons from Dr Natalie Collins’ PFP Assessment Practical and explain why the story your patient tells you is just as valuable as any test you perform.

If you’d like to see exactly how expert physio Dr Natalie Collins assesses PFP, watch her full Practical HERE. With Practicals, you can be a fly on the wall and see exactly how top experts assess and treat specific conditions – so you can become a better clinician, faster. Learn more here.

Why the subjective matters

It’s tempting to jump straight into objective testing, but with PFP, the subjective history lays the foundation for everything that follows.

It provides you with important details about symptom onset, progression, irritability, severity, contributing factors, and the patient’s personal goals. Handled skilfully, it can often provide you with half the diagnosis before you even touch the patient’s knee. This is important, because as Natalie highlights, there are very few reliable clinical tests that can help diagnose PFP!

Differential diagnosis

Anterior knee pain doesn’t always mean PFP. The knee is a busy joint – a thorough subjective assessment helps you rule in or rule out other possibilities such as meniscal involvement, tendinopathy, fat pad pain, or even referred pain from the hip or lumbar spine.

Location, behaviour, and aggravating activities are your signposts. For example, a patient describing more localised pain with jumping/landing activities only may be more likely dealing with tendinopathy, while a diffuse ache, and pain with loaded flexion such as stairs, squatting, and even sitting, point more toward PFP. See Natalie explain in this clip from her Practical:

Notably, people with PFP often struggle to pinpoint their pain. Descriptions are usually vague, with discomfort reported as a circular area around or over the top of the patella, or a semi-circle below the patella.

Finally, if you have identified the patellofemoral joint as the source of pain, understanding whether it might be PFP or patellofemoral osteoarthritis can (for some patients!) be useful information. See Natalie explain this in the below video from her Practical:

Exploring contributing factors

The subjective assessment is your chance to explore the bigger picture in your patient’s PFP. Consider things like:

1. Training load: Has the patient recently changed their activity (e.g., for runners have they increased mileage, intensity, or hill running?)
2. Footwear and equipment: Sudden changes in shoes or surfaces can play a role.
3. Psychosocial influences: Stress, psychological impacts of inactivity, or expectations regarding prognosis can all influence symptoms.
4. Crepitus: Is it present? Is it a concern to them? Is it therefore, something we need to consider in management?
5. Kinesiophobia: fear-avoidance behaviours are common in people with PFP and may exacerbate symptoms and/or contribute to persistent pain. It’s important to understand the patient’s perceptions of their pain and other symptoms (e.g., crepitus), and how these impact their movement.

Recognising these factors allows you to tailor management, avoiding the often ineffective one-size-fits-all approach to PFP.

A brief word on the objective assessment

Of course, the story isn’t complete without objective measures.

Differential tests should be conducted to rule out other sources of pain such as the meniscus, fat pad or iliotibial band. Range of motion, strength testing, functional tasks, and palpation all help confirm your working hypothesis and identify key contributing factors. But these tests only become meaningful when they’re interpreted through the lens of a strong subjective foundation. Here’s a little glimpse of Natalie demonstrating palpation for diagnosis of PFP in her Practical:

Want the full picture? In her full Practical, Natalie takes us through her entire objective assessment, showing how to differentially diagnose PFP from other causes of knee pain.

Wrapping up

In PFP, the subjective assessment is more than just a box-ticking exercise, it’s the foundation of accurate diagnosis and effective management.

By the time you finish taking the patient’s history, you should already have a clear direction for your objective assessment, and potentially even management. The bottom line is, an in-depth subjective assessment is the first step in the appropriate management of patients with PFP, so it’s important to know how to do it right!

This blog only scratches the surface of what’s covered in Dr Natalie Collins’ comprehensive Practical. Check out the full Assessment of Patellofemoral Pain Practical HERE.