Diagnostic Approach for Patellofemoral Pain Syndrome

Clinical History and Physical Examination

The American College of Radiology recommends that the diagnosis of patellofemoral pain syndrome centers on identifying specific pain patterns and functional limitations, including gradual onset diffuse retropatellar and/or peripatellar pain that worsens with activities such as squatting, stair ambulation, and running 1
Patients with patellofemoral pain syndrome often experience pain that develops gradually rather than suddenly, distinguishing it from acute traumatic injuries, and functional limitations in daily activities, sports participation, and quality of life are common presenting complaints 1
The American College of Radiology suggests assessing for psychological comorbidities, as patients with patellofemoral pain are six times more likely to experience anxiety or depression 1
Hip abductor and extensor weakness is a consistent predictor of patellofemoral pain syndrome and should be assessed using hand-held dynamometry or manual muscle testing, according to the American College of Radiology 1

The American College of Radiology recommends that radiographs of the knee are usually appropriate for initial evaluation in patients ≥5 years of age with chronic knee pain, and standard views should include anteroposterior, lateral, and axial radiographs to demonstrate patellar tilt or subluxation 3, 4, 5
The American College of Radiology suggests that MRI without IV contrast may be indicated when radiographs demonstrate small osseous fragments along the medial patellar margin or if there is clinical concern for patellar dislocation-relocation, and CT without IV contrast may be indicated to evaluate patellofemoral anatomy in the setting of chronic pain related to repetitive patellofemoral subluxation 3
The American College of Radiology recommends that if no improvement after 6-8 weeks of consistent conservative therapy, reassessment of diagnosis and consideration of imaging to rule out other pathologies may be necessary 1
Patellar tendinopathy (enthesopathy) may coexist with patellofemoral pain syndrome, according to the American College of Radiology 2
Osteochondral defects or loose bodies requiring MRI evaluation, meniscal pathology in patients with mechanical symptoms, and intra-articular pathology if effusion is present, potentially requiring aspiration for synovial fluid analysis, should be considered in the differential diagnosis, according to the American College of Radiology 3