Knee
Patellofemoral
Evidence: suggestive
Q-Angle Measurement Special Test
Orthopedic Physical Examination & Clinical Assessment Guide
What is it used for?
- Assessing patellar tracking alignment.
How to Perform
- Points: Draw a line from ASIS to mid-patella, and from tibial tuberosity to mid-patella.
- Measurement: Measure the angle at the intersection.
Interpretation of Results
- Normal: Men: 13°; Women: 18°.
- Abnormal: >18° increases risk of subluxation and PFPS.
Clinical Context & Limitations
The Q-Angle Measurement should be considered as one component of a comprehensive musculoskeletal assessment. No single special test has perfect diagnostic accuracy; thus, clinical decision-making should integrate test results with patient-reported symptoms, mechanism of injury, functional impairment, and relevant imaging.
Clinicians should be aware of potential false-positive results in patients with pain sensitisation, muscle guarding, or poor relaxation. For the Knee region, combining the Q-Angle Measurement with complementary examination tests significantly improves overall diagnostic confidence.
References
- Magee, D. J. (2021). Orthopedic Physical Assessment.