Predictive role of ankle MRI for tendon graft choice and surgical reconstruction

Tendon transfers have become a common surgical procedure around the ankle. In this study, we sought to evaluate the existence of a correlation between specific anthropometric parameters and the size of some ankle tendons measured on MRI, in particular those mostly used as graft in ankle surgery.

We recorded gender, height, weight, and body mass index (BMI) of 113 patients (57 females; mean age: 42 ± 18) who underwent ankle MRI. MRI measurements performed by a radiologist were: axial shortest diameter of Achilles (AT), posterior tibialis (PTT), flexor digitorum longus (FDLT), flexor hallucis longus (FHLT), peroneus longus (PLT), and anterior tibialis (ATT) tendons, intermalleolar distance (ID) and talus width (TW). Mann-Whitney U test and Pearson's correlation coefficient were used. After applying the Bonferroni correction for multiple comparisons, statistical significance was set at p < 0.002.

The mean patient height, weight and BMI were 169 ± 9.8 cm (range: 140-193), 72.4 ± 16.4 kg (range: 44-142), and 25 ± 5.7 (range: 16-50), respectively. The mean ankle measurements were: AT = 5.3 ± 1.4 mm, PTT = 3.3 ± 0.6 mm, FDLT = 2.6 ± 0.4 mm, FHLT = 2.7 ± 0.4 mm, PLT = 2.9 ± 0.5 mm, ATT = 3±0.6 mm, ID = 62.9 ± 4.5 mm, and TW = 28.8 ± 2.5 mm. A statistical difference between male and female patients was observed regarding ID (z = -6.955, p < .001), TW (z = -6.692, p < .001), AT (z = -3.587, p < .001), PTT (z = -3.783, p < .001), and FDLT (z = -3.744, p < .001). Both PTT and FDLT showed a significant correlation with ID (p < .001) and TW (p < .001). ATT size was significantly correlated with weight, ID and TW (all with p < 0.001). PLT and AT showed a significant correlation only with ID and weight (p ≤ .001), respectively.

Our data might help orthopaedists in preoperative planning to identify the best graft for ankle surgical procedures including tendon transfers.