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Patellofemoral Instability in the Pediatric Population

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Abstract

Purpose of Review

This review focuses on the etiology, diagnosis, and management of patellar instability in pediatric patients.

Recent Findings

Radiological outcomes such as tibial-tubercle to trochlear groove (TT-TG) distance used in diagnosis are subject to factors of influence such as femoral anteversion and knee flexion angle, and new measure such as tibial-tubercle to posterior cruciate ligament distance as well as TT-TG/trochlear width (TT-TG/TW) are under investigation. To prevent recurrent instability, surgical intervention for acute patellar dislocations may be advantageous compared to conservative management.

Summary

Patellar instability is a common pathology found in pediatric cohorts. Diagnosis can be performed via a combination of history, physical examination maneuvers, and radiological risk factors such as patella alta, patellar tilt, trochlear dysplasia, and elevated TT-TG distances. Current literature advocates the usage of additional radiological measures to TT-TG such as TT-TG/TW, especially as TT-TG varies with age in younger patients. Recent literature potentially suggests the utilization of surgical procedures such as MPFL reconstruction or repair for acute dislocations in the hope of preventing recurrent instability. Special indications for pediatric patients include osteochondral fracture identification to help prevent patellofemoral osteoarthritis. A comprehensive workup and understanding of current literature can aid clinicians in aiming to prevent recurrent patellar dislocation in pediatric patients.

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Authors and Affiliations

  1. Michael DeGroote School of Medicine, McMaster University, 1280 Main Street W, Hamilton, ON, Canada

    Prushoth Vivekanantha

  2. Department of Surgery, Division of Orthopaedic Surgery, McMaster University, Hamilton, ON, Canada

    Dan Cohen, Devin Peterson & Darren de SA

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  1. Prushoth Vivekanantha
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Correspondence to Prushoth Vivekanantha.

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Prushoth Vivekanantha declares that he has no conflict of interest.

Dr. Dan Cohen declares that he has no conflicts of interest.

Dr. Devin Peterson declares that he has no conflicts of interest.

Dr. Darren de SA is an advisory board member for Heron Therapeutics, a consultant for L.E.K Consulting, Atheneum Partners, and Stryker. He is a speaker for Bureau Member (Conmed Linatec) and a working group member for Pendopharm.

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Vivekanantha, P., Cohen, D., Peterson, D. et al. Patellofemoral Instability in the Pediatric Population. Curr Rev Musculoskelet Med 16, 255–262 (2023). https://doi.org/10.1007/s12178-023-09836-0

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