Ankle post-traumatic osteoarthritis: a CT arthrography study in patients with bi- and trimalleolar fractures.
OBJECTIVE
To detect radiographically occult cartilage lesions using CT arthrography (CTa) in patients with malleolar fractures treated with open reduction internal fixation and to correlate the lesions with the functional outcome score.


METHODS
Twenty-one patients (13 men and 8 women, mean age 35 years, range 16-55) underwent ankle CTa after a mean postoperative period of 565 days (range 271-756). CTa images were analyzed by two radiologists. Articular surface post-traumatic collapse and subsequent cartilage defects or erosions were recorded in millimeters and in a binary mode (i.e., present if >50% of cartilage thickness) respectively. The functional outcome was assessed using the American Orthopedic Foot and Ankle Society (AOFAS) score by two orthopaedic surgeons. The statistical analysis correlated the AOFAS score with both imaging parameters and was performed with ANOVA using the MedCalc statistical package, version 11.3.


RESULTS
Of the total of 12 articular surface steps recorded, 2/12 (16.67%) were anterolateral, 4/12 (33.33%) posterolateral, 5/12 (41.67%) anteromedial, and 1/12(8.33%) posteromedial. Of the total of 42 cartilage lesions, 7/42 (16.67%) were anterolateral, 14/42 (33.33%) posterolateral, 12/42 (28.57%) anteromedial, and 9/42 (21.43%) posteromedial. The mean AOFAS score was 8.67 (range 5.95-9.70). There was no statistically significant correlation between the AOFAS score and the post-traumatic internal derangement of the ankle joint (p = 0.524).


CONCLUSIONS
CTa detects radiographically silent cartilage lesions in patients with fractures of the ankle joint. There is no correlation of the extent of lesions and the patient's AOFAS score.
Department of Radiology, University Hospital of Patras, Rion, 26500, Patras, Greece. pantelis.kraniotis@gmail.com
Pantelis
P
Kraniotis
Spyridon
S
Maragkos
Minos
M
Tyllianakis
Theodore
T
Petsas
Apostolos H
AH
Karantanas
D000293:Adolescent; D000328:Adult; D016512:Ankle Injuries / Q000150:complications* / Q000000981:diagnostic imaging*; D001175:Arthrography / Q000379:methods; D005260:Female; D006801:Humans; D008875:Middle Aged; D010003:Osteoarthritis / Q000000981:diagnostic imaging* / Q000209:etiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013639:Tarsal Bones / Q000000981:diagnostic imaging* / Q000293:injuries*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult