Ultrasonography in the differential diagnosis of Achilles tendon injuries and related disorders. A comparison between pre-operative ultrasonography and surgical findings.

Paavola M, Paakkala T, Kannus P, Jarvinen M. Acta Radiol 1998 Nov;39(6):612-9.

To assess the value of US in the diagnosis of various Achilles tendon disorders.

Pre-operative US was compared with surgical findings in 79 patients with an Achilles tendon complaint.

US was highly reliable for verifying a complete Achilles tendon rupture, only one false-negative US examination was found in the 26 surgically verified cases. For diagnosing retrocalcanear bursitis, US was accurate: 6 out of the 8 cases of bursitis were found and there were no false-positive cases. There were also no false-positive US findings in patients with peritendinitis/tendinitis, but 7 false-negative US cases among the 40 surgically verified peritendinitis/tendinitis patients indicated that a negative US finding in a clinically suspected case of peritendinitis/tendinitis is unreliable. US also seemed to be inadequate for differentiating partial tendon rupture from a focal tendon degeneration. Nevertheless, the occurrence and location of such a lesion could be adequately determined by US.

US can reliably be used for locating the Achilles tendon abnormality, estimating its severity, and determining most of the conditions requiring surgical intervention. However, US is not completely reliable for diagnosing peritendinitis and tendinitis, and it cannot be used to differentiate partial tendon ruptures from focal degenerative lesions.