Posterior tibial tendon dislocation: a systematic review of the literature and presentation of a case.

Abstract

In contrast to posterior tibial tendon lesions, dislocations of the posterior tibial tendon are thought to be 'extremely rare'. Diagnostic criteria for this condition have not yet been established. A systematic literature review revealed 61 published cases with posterior tibial tendon dislocation in 36 reports, including eight (12 patients) in French and five (7 patients) in German. We add one more case, which was complicated by a longitudinal tibial tendon tear and a lateral talar dome osteochondral lesion. Fifty-nine cases were descriptively analysed regarding initial injury, subjective symptoms, clinical presentation and findings on different imaging modalities. Treatment and outcome were additionally evaluated. 58.5% of the initial injuries were induced by sport. Initially most cases were misdiagnosed (53.1%). 35.6% of the patients felt a recurrent snapping phenomenon at the medial ankle. Physical examination exhibited a cord-like structure over the medial malleolus in 58.6%, and a posterior tibial tendon (sub)luxation could be provocated in 54.2%. MRI, ultrasound and plain radiography (medial malleolar chip fracture) detected specific findings in 75.0%, 66.7% and 14.7%, respectively. Surgery was done in 83.1% of the patients using varying techniques. The authors judged the treatment result as excellent or asymptomatic in 80%, as good in 12% and as fair or moderate in 8% of the patients. Posterior tibial tendon dislocation occurs more frequently than was previously thought. Misdiagnosis can be avoided, if the surgeon is aware of the condition and combines findings from history, physical investigation and imaging modalities.