A sleeve fracture occurs when a ''sleeve'' of cartilage or periosteum is avulsed with or without an osseous fragment, an injury most commonly reported in the patella. Proximal tibial sleeve fractures are extremely rare and we present a case in an adolescent male who had concomitant osteochondral as well as chondral fractures of his patella. Sleeve fractures present in the skeletally immature, and may look relatively benign on radiographs, but misdiagnosis may lead to adverse consequences. Clinicians should have a high index of suspicion if a child or adolescent presents with a knee injury with clinical concerns regarding the extensor mechanism. Given that the ''sleeve'' of the injury contains tissue with osteogenic potential, we recommend that displaced proximal tibial sleeve fractures should be managed operatively to avoid dysfunction of the extensor mechanism. These patients should also have perioperative assessment for occult osteochondral and chondral injuries that are potentially repairable and thus may have implications for prognosis.
Keywords: Chondral patella fracture; Osgood–Schlatter disease; Osteochondral patella fracture; Sleeve fracture.