Abstract
Introduction: A dysplastic trochlea. may be missed on conventional roentgenography due to superimposition effects of the distal femoral groove. Methods: Measurements of (1) the sulcus angle, (2) the lateral trochlear slope angle and (3) the lateral to medial trochlear ratio were compared between plain axial radiographs and axial magnetic resonance images (MRI) in 24 patients suVering from clinical patellofemoral instability. Trochlear dysplasia was classiWed into type A through D on MR images. Results: Measurements for (1) were significantly different among all dysplasia types. It was 135.6° ± 19.8° on X-ray while it was above 180° on MRI within dysplasia type D patients. Measurements for (2) were different among all dysplasia types, reaching statistical significance in type B dysplasia patients. Differences between radiographs and MRI for (3) were not significant, while only on MRI the ratio increased with increasing degree of dysplasia. Conclusion: The investigation illustrates that plain axial radiographs do not represent the natural bony trochlear morphology and may mislead further clinical management.
| Original language | English |
|---|---|
| Pages (from-to) | 335-340 |
| Number of pages | 6 |
| Journal | Archives of Orthopaedic and Trauma Surgery |
| Volume | 130 |
| Issue number | 3 |
| DOIs | |
| State | Published - Mar 2010 |
Keywords
- Angle
- Magnetic resonance imaging
- Patella instability
- Radiograph