Achilles tendon after percutaneous surgical repair: serial MRI observation of uncomplicated healing

The purpose of this study was to prospectively explore the MRI features of normal healing of the expected residual tendon gap in the Achilles tendon after percutaneous surgical repair.

MR images of the Achilles tendon were obtained approximately 4, 8, and 12 weeks after surgery. Assessment of MR images was focused on the presence of residual tendon gap and gap length, Achilles tendon contour, and contrast enhancement in the ruptured area. Cases of open surgical repair were used for comparison. We attempted to statistically compare the timing of tendon gap disappearance within the percutaneous surgical repair group and between the percutaneous and open surgical repair groups.

A total of 30 tendons repaired with percutaneous surgical technique and 10 repaired with open surgical technique were evaluated. At the first, second, and third MRI sessions of the percutaneous surgical repair group, a residual gap was found in 100%, 80%, and none of the tendons on T1-weighted images and in 87%, 63%, and none of the tendons on T2-weighted images. Achilles tendon contour was visualized in 30%, 90%, and 100% of the tendons on T1-weighted images and 90%, 100%, and 100% of the tendons on T2-weighted images. Intratendinous enhancement was present in 100%, 73%, and 7% of the tendons in the percutaneous surgical repair group. Ring-shaped peritendinous enhancement was recognized at the third session in all subjects. A significantly longer time was required for tendon gap disappearance after percutaneous than after open surgical repair.

The time course of the MR findings in the ruptured Achilles tendon after percutaneous surgical repair appears to reflect regular healing.