Partial double-layered patella in a nondysplasic adolescent.

Area of Science:

• Orthopedics
• Radiology
• Medical Imaging

Background:

• Double-layered patella (DLP) is a rare patellar formation abnormality, often associated with multiple epiphyseal dysplasia.
• DLP is a type of bipartite patella resulting from a coronal septum dividing the patella into anterior and posterior segments.

Observation:

• A 13-year-old male presented with knee pain after an injury, initially diagnosed with a patellar fracture.
• Radiography revealed an external partial DLP, with CT and MRI confirming partial DLP and bone marrow edema without a fracture.

Findings:

• This case represents a rare instance of partial DLP in a patient without any signs of bone dysplasia.
• The imaging findings underscore the potential for confusion between partial DLP and patellar fractures on standard radiographs.

Implications:

• Accurate differentiation of DLP from patellar fractures is crucial for appropriate patient management.
• This case expands the understanding of DLP presentation, particularly in the absence of associated bone dysplasia.