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Patellar Tracking: An Old Problem with New Insights.

Robert E Watts¹, Tetyana Gorbachova¹, Russell C Fritz¹

¹From the Departments of Radiology (R.E.W., A.M.L., R.D.B.) and Orthopaedic Surgery (S.L.S.), Stanford University School of Medicine, 300 Pasteur Dr, Stanford, CA 94305-5101; Department of Radiology, Einstein Healthcare Network and Jefferson Health, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA (T.G.); Department of Musculoskeletal Radiology, National Orthopedic Imaging Associates, Greenbrae, CA (R.C.F.); Department of Musculoskeletal Radiology, Atlantic Medical Imaging, Galloway, NJ (S.S.S.); Department of Radiology, Benning Martin Army Community Hospital, Fort Benning, GA (J.K.); Departments of Radiology and Biomedical Data Science, Stanford University, Stanford, CA (A.S.C.); and Department of Orthopaedic Surgery, Lucile Packard Children's Hospital at Stanford, Palo Alto, CA (K.G.S.).

Radiographics : a Review Publication of the Radiological Society of North America, Inc

|June 1, 2023

Summary

This summary is machine-generated.

This review covers imaging for patellofemoral instability, focusing on anatomy, clinical evaluation, and diagnostic imaging before osteoarthritis. Key aspects include the medial patellofemoral ligament (MPFL) and osteoarticular abnormalities.

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Area of Science:

Radiology
Orthopedic Surgery
Medical Imaging

Background:

Patellofemoral pain and instability are frequent clinical issues requiring imaging.
Understanding pre-osteoarthritis imaging findings is crucial for radiologists.
The medial patellofemoral ligament (MPFL) is key in stabilizing the patella.

Purpose of the Study:

To provide radiologists with a comprehensive review of patellofemoral instability.
To highlight relevant anatomy, clinical evaluation, diagnostic imaging, and treatment options.
To summarize validated measurements for common osteoarticular abnormalities.

Main Methods:

Review of key aspects of patellofemoral instability relevant to radiologists.
Discussion of anatomy, clinical presentation, and imaging modalities (radiography, MRI, dynamic imaging).
Summary of validated radiologic measurements for malalignment, dysplasia, and lateralization.

Main Results:

Medial patellofemoral ligament (MPFL) is the primary restraint to lateral patellar displacement.
Osteoarticular abnormalities like trochlear dysplasia predispose to instability.
Radiography is the initial imaging choice; MRI is common preoperatively.

Conclusions:

Accurate imaging and understanding of anatomy are vital for managing patellofemoral instability.
Conservative treatment is primary for pain; surgery (e.g., MPFL reconstruction) is an option for instability.
Postoperative imaging evaluates complications such as graft failure and subluxation.