Authors:
T. Luijkx1, M. Maas2; 1Amsterdam, Utrecht/NL, 2Amsterdam/NL
DOI:
10.1594/essr2015/P-0116
Conclusion
Figure 9 illustrates the variation in ECU displacement in relation to wrist position in a patient who underwent three MRI scans with varying wrist positions,
serving as an example of the findings from this study:
The ECU tendon has a tendency to be subluxated from the ulnar groove in supination.
Although this is also observed in pronation,
the extent of subluxation is more pronounced in supination and is also more frequent. Our study shows that there is a clear relationship between wrist position (radio-ulnar angle) and ECU displacement,
even when corrected for ECU abnormalities,
ulnar-sided symptoms,
age and gender.
Of the latter variables only MRI abnormalities of the ECU are significantly related to ECU displacement.
These findings suggest that radiologists should be cautious to interpret a displaced ECU tendon as pathological,
especially in supination and also indicate that confusion may be limited by avoiding scanning in supination.
In wrist supination ECU subluxation is more frequent and more pronounced,
irrespective of tendon pathology or presence of symptoms.
To minimise the possibility of physiological ECU subluxation,
and subsequent inconclusive MRI reports,
radiologists should make sure supination is prevented as much as possible.