- [Home](https://ortopediaevolutiva.com/en) - [Pediatric Orthopaedics Blog — Dr. Priano](https://ortopediaevolutiva.com/en/blog) - First patellar dislocation in children: what MRI adds # First patellar dislocation in children: what MRI adds January 12, 2026 2 min read Edited and medically reviewed by [Dr. Daniele Priano](https://ortopediaevolutiva.com/en/about) ![First patellar dislocation in children: what MRI adds](https://ortopediaevolutiva.com/blog-images/prima-lussazione-rotula-bambini-risonanza-magnetica-neutral-v1.webp) This English version is based on the original Italian article. For wording nuances, you can refer to the Italian version. ## In short, for parents - • MRI can show injuries that an X-ray misses after a first kneecap dislocation. - • Significant injuries can influence the choice of treatment. - • MRI is not always needed, but it can be useful when swelling, pain or locking persists. After a first [patellar dislocation](https://ortopediaevolutiva.com/en/conditions/patellar-dislocation), X-rays may be normal or show only modest findings. Magnetic resonance imaging (MRI) allows for the evaluation of ligamentous and osteochondral lesions that can alter treatment. A systematic review from 2026 collected 12 pediatric studies with MRI performed after the first episode. [1] ## Most Frequent Findings The aggregated frequencies reported in the review were high: - complete MPFL rupture: 47%; - partial MPFL lesion: 41%; - osteochondral damage: 50%; - intra-articular loose bodies: 34%. [1] When the osteochondral lesion was isolated, the most frequent location was the medial facet of the patella compared to the lateral femoral condyle. These findings do not automatically constitute a surgical indication. However, a significant osteochondral fragment or a loose body can quickly change the treatment pathway compared to simple conservative management. ## When MRI is Particularly Useful Hemarthrosis or significant swelling, marked pain, locking, mechanical symptoms, and radiographic or clinical suspicion of an osteochondral lesion are situations where I more readily use MRI. MRI also helps to define the MPFL lesion and the anatomy predisposing to instability, information useful in counseling about the risk of recurrence. ## MRI for Everyone After the First Episode? The review shows a high frequency of associated findings, but the included studies are heterogeneous in terms of indication and timing of the examination. [1] In centers where MRI is quickly available, a relatively low threshold can be adopted, especially in cases with hemarthrosis. In other contexts, rigorous clinical selection remains reasonable. The important point is that a negative X-ray does not exclude significant osteochondral damage. If the clinical picture is not that of a simple episode, MRI offers information that X-rays cannot provide. Disclaimer: informational content, not a substitute for an individual specialist evaluation. ## Reference [1] Reed JM, et al. Frequency of Adjunctive MRI Findings on First-Time Patellar Dislocations in Pediatric Patients: A Systematic Review. Am J Sports Med. 2026. DOI: 10.1177/03635465251383851. PMID: 41508815. ## Complete knee and sport pathway This page is part of the knee and sport pathway. The sports injuries page covers the overall picture. - [1 Overview: sports injuries in the growing athlete How the knee and the growing musculoskeletal system respond to sport.](https://ortopediaevolutiva.com/en/conditions/sports-injuries) - [3 Patellar instability From the first dislocation to recurrent forms: assessment and options.](https://ortopediaevolutiva.com/en/conditions/patellar-dislocation) [When surgery may be needed](https://ortopediaevolutiva.com/en/surgery/patellar-dislocation) - [4 Ligaments and menisci Technical content also aimed at physiotherapists: pathway after ACL reconstruction in the skeletally mature patient.](https://ortopediaevolutiva.com/en/rehabilitation/acl-reconstruction) - [5 Osteochondral lesions Osteochondritis dissecans: when cartilage and subchondral bone are involved.](https://ortopediaevolutiva.com/en/conditions/osteochondritis-dissecans-knee) ![Dott. Daniele Priano](https://ortopediaevolutiva.com/assets/doctor-avatar-3d-CTvqnoPa.webp) ### Concerned about your child? If you recognize any of these signs in your child, a specialist assessment can give you clarity. I see children at Gaetano Pini and CTO institutes in Milan. 5.0 · Google & MioDottore [Book a private visit](https://ortopediaevolutiva.com/en/locations#prenota) ### Related Conditions [Patellar dislocation](https://ortopediaevolutiva.com/en/conditions/patellar-dislocation) ### Related Surgery Pages [Patellar dislocation surgery](https://ortopediaevolutiva.com/en/surgery/patellar-dislocation) ### Related Exercises [Exercises for Patellar dislocation](https://ortopediaevolutiva.com/en/parents-kids/exercises/knee/patellar-dislocation) ### Related Articles [Kirschner Wire Infection in Children: When Can It Become Osteomyelitis? Read](https://ortopediaevolutiva.com/en/blog/kirschner-wire-infection-children-osteomyelitis-risk)[A benign bone lesion in a child: can they still play sport? Read](https://ortopediaevolutiva.com/en/blog/benign-bone-lesion-child-sport)[Persistent pain after trauma with normal X-ray: how to interpret it Read](https://ortopediaevolutiva.com/en/blog/child-persistent-pain-normal-x-ray) ![Dott. Daniele Priano](https://ortopediaevolutiva.com/assets/doctor-avatar-3d-BiLSxBxW.webp) Author and medical reviewer ## Dr. Daniele Priano [Pediatric orthopaedic care in Milan](https://ortopediaevolutiva.com/en) — Gaetano Pini & CTO [Read full bio](https://ortopediaevolutiva.com/en/about) --- Canonical: https://ortopediaevolutiva.com/en/blog/first-patellar-dislocation-in-children-mri Le informazioni cliniche sono divulgative e non sostituiscono una valutazione medica diretta.