Acute inversion injury of the ankle without radiological abnormalities: assessment with high-field MR imaging and correlation of findings with clinical outcome.
BACKGROUND
Acute inversion injuries of the ankle are the most common sports accidents, accounting for approximately 10% of emergency room admissions. In up to 85%, an injury of the lateral collateral ligaments is observed. Classically, the assessment of these injuries has relied on clinical examination and radiographs, including stress views. The aim of our study was to correlate prospectively the findings of high-field 3 T MRI in acute ankle distortion with clinical outcome.


METHODS
During a 6-month period, 38 patients were prospectively included. MRI was performed within 48 h of trauma and clinical examination using a protocol consisting of axial T2-weighted and coronal and sagittal T1-weighted images and a sagittal proton density (PDw) sequence. Each ligament injury was graded on a three-point scale. Functional outcome was evaluated using the AOFAS ankle-hindfoot scale.


RESULTS
In 24/38 patients (63.12%), ligament injury was observed. In 22/24 cases, this was an injury of the lateral ligaments and in 2/24 cases of the medial ligaments. Injury of the syndesmosis occurred in three patients, a bone bruise in four, and an osteochondral lesion in three cases. Patients with an injury of two or more ligaments or a bone bruise had a lower AOFAS score and returned to sports activities and full weight-bearing later (P < 0.01).


CONCLUSIONS
MR imaging at 3 Tesla is an independent predictor for clinical outcome. Therefore MRI may be beneficial in those cases where the findings influence further treatment.
Langner
Inga
I
Department of Trauma and Orthopedic Surgery, Emergency Department, Ernst-Moritz-Arndt-University Greifswald, Greifswald, Germany.
Frank
Matthias
M
Kuehn
Jens Peter
JP
Hinz
Peter
P
Ekkernkamp
Axel
A
Hosten
Norbert
N
Langner
Soenke
S
D000328:Adult; D000368:Aged; D016512:Ankle Injuries / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010808:Physical Examination; D016896:Treatment Outcome