Patellofemoral Pain (PFP)

This page is the dedicated Knee sub-section for patellofemoral pain and includes the complete teaching content from the source material.

Primary resources:

• Patellofemoral Pain reference library (PDFs)
• Back to Knee Overview

Clinical Presentation

Patellofemoral pain typically presents with gradual, non-traumatic onset of diffuse peripatellar or retropatellar pain. Symptoms are usually aggravated by flexion-loaded tasks such as squatting, stairs, running, hopping, kneeling, and prolonged sitting (the “movie theatre sign”).

Associated features can include crepitus, intermittent swelling, and perceived giving way related to quadriceps inhibition rather than true structural instability.

Historical Evolution: How Thinking Changed

The field has moved from a mainly structural, local-knee and malalignment-focused model to a broader clinical syndrome and load-tolerance model. In practice this means less weight on imaging and isolated special tests, and more weight on symptom behavior, functional aggravators, prognosis, education, and active rehabilitation.

How Assessment Changed

• Earlier literature: assessment centred on maltracking, chondromalacia, alignment, and radiographs; PFP was treated mostly as a local structural problem.
• 2000s to mid-2010s: shift to clinical diagnosis from history and symptom provocation (squatting, stairs, running, prolonged sitting), with less routine imaging.
• Late 2010s to now: broader assessment of impairments, function, irritability, PROMs, patient goals, and prognosis; imaging mainly for atypical presentations, failed care, or alternate pathology.

How Management Changed

• Earlier literature: rest, activity reduction, local quadriceps focus, taping/bracing, and occasional surgery.
• 2000s to mid-2010s: exercise became core care; evidence supported hip-focused exercise alongside knee exercise instead of isolated VMO approaches.
• Late 2010s to now: multimodal, patient-tailored conservative care with education + exercise as the base treatment.

Biggest Modern Shifts

• Passive to active care: exercise therapy is now the backbone.
• Isolated knee to combined hip+knee rehab: evidence favors combined programs.
• Generic protocols to load-based tailoring: education, load management, and graded return are central.
• Wait-and-see to early active treatment: education plus physical treatment outperforms wait-and-see in short-term outcomes.
• Routine adjuncts to selective adjuncts: foot orthoses and taping help selected patients; passive modalities are not favored as standalone care.
• Liberal to cautious escalation: medications, injections, and surgery are later-line options after strong conservative care.

How Lifespan Thinking Changed Care

• Adolescents: no longer assumed self-limiting; early management with load strategies, education, family support, and return-to-sport planning is recommended.
• Adults and runners: greater emphasis on activity-specific care including running retraining and movement modification when relevant.
• Persistent and older patients: persistent PFP is taken seriously with concern for chronic symptoms, sensitization in some patients, and overlap with patellofemoral OA.

Patient Presentation Categories

1. Active/Sporting patient: often adolescents, young adults, military recruits, or runners; symptoms commonly follow abrupt load spikes (“too much, too soon”) and often present under 12 months duration.
2. Sedentary patient: often inactive/overweight with pain triggered by positional stress and ADLs; frequently presents after longer duration (>12 months).
3. Adolescents (continuum): recent-onset cases often continue sport; long-standing cases may progress to frequent pain, medication use, and major sport withdrawal.
4. Females: around twice the risk of PFP versus men, often influenced by hip strength, Q-angle, and dynamic valgus factors.
5. Severe/chronic PFP: may include psychosocial distress (kinesiophobia, catastrophizing, anxiety/depression) and altered pain processing (hyperalgesia/allodynia).

Clinical Assessment

Subjective Assessment

• Pain characteristics: insidious, diffuse peripatellar/retropatellar pain pattern.
• Aggravating factors: pain reproduced by flexed-knee loading tasks such as squat, stairs, running, jumping, kneeling, and prolonged sitting.
• Load/activity history: identify recent activity spikes and lifestyle/training changes affecting tissue tolerance.
• Red flags and differential diagnosis: screen for systemic illness, trauma, true locking, major effusion, and referred lumbar/hip pain.
• Psychosocial yellow flags: fear-avoidance, kinesiophobia, catastrophizing, anxiety/depression, and beliefs about pain.

Physical Examination

• Functional provocation: squatting is highly recommended; stair descent and eccentric step-down testing are also useful.
• Patellar tests: patellar facet tenderness and selected patellar mobility/instability testing support diagnosis and differential diagnosis.
• Caution with Clarke’s test: historically common but highly provocative and poorly specific; not relied upon in modern guidance.
• Impairment screen: quadriceps and hip strength (abductors/extensors/external rotators), movement coordination (dynamic valgus), flexibility, and foot mobility/posture (e.g., navicular drop).

Interpretation Principles

1. Confirm diagnosis: retropatellar/peripatellar pain + reproduction with flexed-knee loading + exclusion of other causes.
2. Classify subgroup drivers: overload, muscle performance deficits, movement coordination deficits, or mobility impairments.
3. Imaging role: not required for routine diagnosis; reserved for atypical cases, red flags, suspected alternate pathology, or poor response to conservative care.

▶ Show Knowledge Check

Management

Core Principles for All Patients

• Avoid wait-and-see: passive observation is associated with poorer outcomes.
• Exercise therapy as cornerstone: combined hip-targeted and knee-targeted strengthening is consistently favored.
• Education underpins all care: load management, activity modification, fear-belief reframing, and reassurance.
• Adjunctive interventions: tailored patellar taping or prefabricated foot orthoses can help short-term pain and participation.
• Not recommended as standalone treatments: therapeutic ultrasound, electrotherapy, dry needling, and isolated manual therapy.
• Escalation: surgery and injections are not routine and are considered only in specific refractory presentations after comprehensive conservative care.

Subgroup-Targeted Management

1. Overuse/overload: relative rest and load management, with early graded return.
2. Muscle performance deficits: progressive strengthening of hip/gluteal and quadriceps systems.
3. Movement coordination deficits: visual/verbal cueing during functional tasks; running gait retraining (including cadence adjustments) where indicated.
4. Mobility impairments: for hypermobility (e.g., pronation) use prefabricated orthoses and/or taping; for hypomobility include stretching and targeted soft tissue/patellar mobility approaches.

Lifespan and Prognosis Considerations

• Adolescents: monitor persistence risk and protect sport participation with structured progression.
• Runners/active adults: adjust loading strategy to sport demands and movement profile.
• Persistent/chronic cases: include psychosocial and pain-processing assessment; consider longer-term patellofemoral OA implications.

▶ Show Knowledge Check

▶ Show Knowledge Check

▶ Show Knowledge Check