What is the characteristic feature of Osgood Schlatter disease on X-ray (x-ray)?

Characteristic Features of Osgood-Schlatter Disease on X-ray

The characteristic radiographic feature of Osgood-Schlatter disease is fragmentation of the tibial tuberosity with irregularity of the apophysis. 1

Radiographic Findings

Osgood-Schlatter disease (OSD) is a traction apophysitis affecting the tibial tuberosity in growing children, typically boys aged 12-15 years and girls aged 8-12 years. The key radiographic findings progress through stages:

Acute Stage:

• Blurred margins of the patellar tendon due to soft tissue swelling 2
• Irregularity of the apophysis with separation from the tibial tuberosity 3
• Enlarged radiolucent line at the apophyseal plate of the tibial tuberosity

Subacute Stage:

• Bone fragmentation at the tibial tuberosity (visible after 3-4 months) 2
• Soft tissue swelling resolves, but bony ossicle remains

Chronic Stage:

• The bone fragment may fuse with the tibial tuberosity 2
• Tibial tuberosity may appear normal or enlarged

Clinical Correlation

MRI is useful for evaluating Osgood-Schlatter or Sinding-Larsen-Johansson syndrome when radiographs are inconclusive 1. However, radiography remains the initial imaging modality of choice for diagnosis.

The radiographic findings should be correlated with clinical symptoms:

• Pain and tenderness over the tibial tuberosity
• Local swelling at the insertion of the patellar tendon
• Symptoms exacerbated by jumping, running, and kneeling activities 3

Ultrasound Findings

While not the primary focus of your question, it's worth noting that ultrasound can complement radiographic findings by showing:

• Cartilage swelling (present in 100% of cases in one study) 4
• Tibial tuberosity fragmentation (75% of cases) 4
• Diffuse thickening of the patellar tendon (22% of cases) 4
• Bursitis of the infrapatellar bursa (17% of cases) 4

Management Implications

The radiographic findings help guide management:

• 90% of patients respond to conservative treatment including rest, icing, and activity modification 3
• Surgical excision of the ossicle may be indicated in skeletally mature patients who remain symptomatic despite conservative measures 3

Common Pitfalls

• Don't confuse normal developmental variations of the tibial tuberosity with pathologic fragmentation
• Radiographs may appear normal in early disease
• Bilateral comparison views may be helpful as OSD can be bilateral
• The condition is self-limiting and typically resolves with closure of the tibial growth plate 3