Pediatric Patellar Avulsion Frx (Sleeve Fracture)


- See: Osteochondral Frx

- Discussion:
    - type of osteochondral frx of the patella which results from high impact jumping activities
            - mechanism: eccentric contraction of the quadriceps on the flexed knee;
    - occurs when the inferior pole of the patella of a child or adolescent is pulled off together with a large amount of articular cartilage and retinaculum;
            - superior fragment (devoid of cartilage) is pulled superiorly;          
    - diff dx:
            - Bipartite patella
            - Sindig-Larsen-Johanssen disease


- Exam:
    - hemarthrosis:
    - local pain & tenderness
    - extension lag (inability to fully extend the knee actively);


- Radiographs:
    - small bone fragment will suggest the diagnosis, but it can be difficult to see on standard radiographs;
    - high-riding patella in comparison with contralateral side;


- MRI: study of choice to confirm the dianosis;


- Treatment:
    - these injuries require surgical intervention w/ anatomical reduction and rigid internal fixation of the patellar frx and the sleeve of articular fracture;
    - remember the distal fragment can be much larger than it appears on the radiographs because it consists largely of cartilage



Sleeve fractures of the patella in children: a report of three cases.

Sleeve fracture of the patella in children. A report of five cases.

Avulsion fractures of the patella.

Partial sleeve fractures of the tibia in children: an unusual fracture pattern.



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Wednesday, February 6, 2013 4:53 pm