Panner Disease

• Etiology:
  — Osteochondrosis of capitellum due to disruption of vascular supply to epiphysis, similar to Legg-Calve-Perthes
  — Injury to tenuous vascularity of capitellum which is supplied by small posterior perforating-end arteries traversing a pliable and compressible epiphyseal cartilage
  — Ischemia of ossific nucleus causes disordered endochondral ossification
• Imaging Radiograph: Demineralization with irregularity and fragmentation and sclerosis of capitellum
• Imaging MRI:
  — Loss of normal fatty marrow signal involving entire capitellum ossification center
  — Articular cartilage is intact
  — Stages include ischemia and necrosis followed by revascularization and re-ossification
  — T1WI: Capitellum has low signal intensity
  — T2WI: Capitellum has high signal intensity
• DDX: Osteochondritis dissecans of the elbow in patients greater than 11 years old
  — Panner disease: Younger 7-12 years, affects all or part of capitellum, normal overlying cartilage, no loose body formation
  — Osteochondritis dissecans of the elbow: Older age group 12-15 years, affects anterolateral capitellum, may have overlying cartilage defects or loose bodies
• Complications:
• Treatment: With rest normal capitellar growth resumes without long-term sequelae
• Clinical:
  — Presents with dull pain or stiffness
  — Associated with prior trauma in 50%
  — Almost always occurs in dominant elbow of boys 5-12 years old with history of throwing

Radiology Cases of Panner Disease