Comparison of ultrasonography and magnetic resonance in the postoperative monitoring of complete subcutaneous rupture of the Achilles tendon]

The diagnostic accuracy of US and MRI in the subcutaneous rupture of the Achilles tendon has already been assessed. We used both techniques to study the Achilles tendon during the postoperative repair process after surgery according to Bosworth. The results were compared and discussed in relation to clinical recovery. Ten patients with complete subcutaneous rupture of the Achilles tendon were followed-up with physical examination and submitted to US and MR studies 40, 60 and 90 days postoperatively. Eighty patients recovered in the expected time, while 2 took longer. At 90 days, the US findings in 7 patients and the MR findings in 8 patients who recovered in the expected time could be considered normal. US poorly distinguished the tendon from the reinforcement flap because of gross tendon echostructure. The tendon and the reinforcement flap were not distinguishable at MRI because they were uniformly hypointense. Clinical recovery appeared as a hyperechoic structure and a gross fibrillar pattern at US and as a hypointense structure with some small hyperintense areas at MRI. US and MRI were in disagreement in one patient with a postoperative algodystrophic syndrome, where US showed some alterations which were considered false positives because of clinical recovery and negative MR findings. US and MR patterns were considered abnormal in the 2 patients with delayed recovery. US showed persistent hyperechoic areas within the tendon, while the MR signal was of intermediate intensity in the tendon and reinforcement flap. To conclude, we believe that US is an appropriate technique for the postoperative follow-up of complex subcutaneous ruptures of the Achilles tendon. Additional MRI should be performed in all the cases where US findings are in disagreement with clinics.