Subacute superior patellar pole sleeve fracture

Area of Science:

• Orthopedic Surgery
• Pediatric Traumatology
• Radiology

Background:

• Patellar fractures are rare in children, accounting for 1% of pediatric fractures.
• Sleeve avulsions of the inferior patellar pole are common, but superior pole avulsions are exceptionally rare, with limited case reports.
• These injuries typically affect adolescents following forceful knee flexion or direct anterior trauma.

Observation:

• A 15-year-old male presented with a subacute superior pole sleeve fracture after a left knee injury.
• Initial radiographs were negative, but subsequent imaging revealed hemarthrosis and suprapatellar calcification.
• MRI initially suggested a distal quadriceps tendon tear, delaying definitive diagnosis.

Findings:

• The patient developed a limp and inability to perform a straight leg raise, indicating significant extensor mechanism disruption.
• Surgical repair confirmed a superior pole sleeve fracture, highlighting the challenges in diagnosing this rare injury.
• Radiographic signs like patella baja, anterior tilt, and suprapatellar calcifications are key indicators.

Implications:

• Emphasizes the importance of recognizing the subtle radiographic and clinical signs of superior pole sleeve fractures in adolescents.
• Highlights the potential for misdiagnosis with initial imaging, underscoring the need for high clinical suspicion.
• Suggests that a thorough understanding of this injury pattern can improve diagnostic accuracy and patient outcomes.