Syndesmotic stability: Is there a radiological normal?-A systematic review.

BACKGROUND: Syndesmotic injury and instability poses a diagnostic challenge with unreliable clinical tests and inconsistent radiologic measures. Thus, used widely in clinical practice, there is huge debate pertaining to the reliability and validity of the radiologic parameters used for syndesmotic instability.

OBJECTIVE: Hence the purpose of the review was to explore the normal radiologic measures and morphometrics of distal tibiofibular syndesmosis and its relationships, which can aid in diagnosing syndesmotic instability.

METHOD: Computerised literature searches was performed for articles published in English using Pubmed, from inception through June 2016. All published articles reporting the normal anatomic and morphometric measures of distal tibiofibular syndesmosis with the use of any radiological modality individually or in combination, either in cadaveric or in live subjects were included. Studies done on or reporting of measures in healthy ankles or radiologically normal ankles were only included.

RESULTS: In this review wide anatomic and morphologic variability was observed amidst the landmarks used commonly for assessing syndesmotic instability and hence the normal measures. Further age and gender based variations were seen across the most commonly used radiologic measures for syndesmotic instability diagnosis, demanding the modification of existing radiologic criteria.