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The a angle: a quantitative measurement of patella alignment and realignment
The Journal of Orthopaedic and Sports Physical Therapy
|January 1, 1990
Summary
This case study presents the A angle, a new measurement for patellar tracking, and its application in treating an 11-year-old with patellofemoral pain. The A angle may indicate patellofemoral issues, aiding in clinical assessment and treatment.
Area of Science:
- Orthopedics
- Sports Medicine
- Biomechanics
Background:
- Patellofemoral pain is a common condition in young athletes.
- Accurate clinical measurements are needed to assess patellar alignment and function.
Purpose of the Study:
- To introduce a novel clinical measurement for patellar glide, tilt, and rotation.
- To define a quantitative measurement, the A angle, for assessing patellofemoral pathomechanics.
Main Methods:
- A case study involving an 11-year-old female with patellofemoral pain.
- Treatment protocol included patellar taping for alignment, stretching lateral structures, and strengthening exercises (functional training, isokinetics) focusing on the vastus medialis obliquus.
- Measurement of patellar glide, tilt, and rotation, and calculation of the A angle.
Main Results:
- The A angle was defined as a quantitative measurement.
- The treatment protocol aimed to improve patellar alignment and function.
Conclusions:
- The A angle shows potential as a sensitive clinical indicator of patellofemoral pathomechanics.
- This measurement could aid in the diagnosis and management of patellofemoral pain syndrome.
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