Tj. Vogl et al., MAGNETIC-RESONANCE-IMAGING IN THE DIAGNOSIS OF ACUTE INJURED DISTAL TIBIOFIBULAR SYNDESMOSIS, Investigative radiology, 32(7), 1997, pp. 401-409
RATIONALE AND OBJECTIVES. This study assessed the diagnostic potential
of magnetic resonance imaging for the evaluation of the tibiofibular
syndesmosis. METHODS. A total of 38 patients with an acute ankle traum
a and clinical suspicion of a syndesmotic tear were prospectively stud
ied with conventional plain film radiography and magnetic resonance im
aging, Magnetic resonance imaging studies included plain T1-weighted (
T1-w) and T2-weighted (T2-w) sequences and contrast-enhanced T1-w sequ
ences 0 to 3 days after trauma. All images were read by two independen
t radiologists before surgical intervention, Sensitivity and specifici
ty were determined for the two observers and the concordance of the tw
o observers were calculated using the interobserver analysis (Kappa-Te
st), Intraoperative inspection (n = 21) revealed rupture of the anteri
or tibiofibular ligament (ATIF) in 15 patients, intact ATIF in 6 patie
nts, and intact posterior tibiofibular ligament (PTIF) in 21 cases, Cl
inical and follow-up examinations revealed an intact syndesmotic compl
ex in another 17 patients. RESULTS. Primary diagnostic criteria for di
agnosing a ligamentous tear included tibiofibular diastasis in convent
ional plain films; nonvisualization of the ATIF; an abnormal course, a
wavy, irregular contour of the ligament; increased signal intensity o
f the ligament in T2-w sequences, in plain T1-w sequence, and marked e
nhancement in T1-w after contrast, Important secondary signs were defi
ned as joint fluid in the tibiofibular space and prolapse of interspac
e fat, Highest diagnostic accuracy was achieved if three or more diagn
ostic criteria could be visualized, Both readers performed best with t
he enhanced T1-weighted and the T2-weighted images in transverse orien
tation, The interobserver analysis resulted in high concordance: Kappa
= 0.9 (confidence interval: 0.76 to 1.00) for all patients, and in Ka
ppa = 0.76 (confidence interval: 0.45 to 1.0) for surgically treated p
atients. CONCLUSIONS. Magnetic resonance imaging of the syndesmotic co
mplex is a highly sensitive and specific tool for the pretherapeutic e
valuation of syndesmotic injury.