Knee
Analysis: the checklists
The AP radiograph
Adults: a five-point checklist
Check:
2. The head and neck of the fibula.
□ Each plateau should be smooth. No steps, no layering, no disruptions.
□ The subchondral bone should not show any focal increase in density.
4. The patella. Look through the superimposed femur.
5. Finally, check for any small fragments of bone—anywhere at all.
In the normal knee a perpendicular line drawn at the most lateral or medial margin of the femur should have no more than 5 mm of adjacent tibia outside of it. If this rule is broken suspect a plateau fracture.
Children: an eight-point checklist
1–5 as for adults, but also check:
6. The growth plates of femur, tibia, and fibula. Is there an epiphyseal fracture? (See pp. 14–17).
7. The cortex of the femur and tibia. Is there a Greenstick or Torus fracture? (See pp. 18–19.)
8. The condylar surfaces of the femur. Is there an osteochondral lesion/fracture? (See pp. 28–29.)
The lateral radiograph
It is important to understand the normal and abnormal appearance of the suprapatellar bursa—if abnormal, this often suggests a fracture or ligament damage4–6.
Adults and children: a six-point checklist
Check:
1. For a joint effusion4–7. Present if the suprapatellar strip exceeds 5 mm (see below).
2. For a fat–fluid level in the suprapatellar bursa… an intra-articular fracture.
3. The condylar surfaces of the femur. Are they smooth?
4. The patella. Is the articular surface smooth?
