The Natural History of the Development and Resolution of Achilles and Patellar Tendon Sonographic Abnormalities in a Collegiate Cohort.

To prospectively identify the development and regression of Achilles and patellar sonographic abnormalities in collegiate athletes. Prior to the beginning of their seasons, the Achilles and patellar tendons of collegiate athletes were sonographically videoed by an experienced sonographer. Subjects were then re-recorded at the end of 1 year of competition in an identical manner. Measurements were obtained using consistent predetermined protocols for each participant. Videos of the results were assessed in a blinded manner for echogenicity, tendon thickening, and neovascularization. A total of 147 patellar and 148 Achilles tendons were recorded, with 40.1% of patellar and 16.2% of Achilles tendons identified to have abnormalities at baseline. Of all tendons analyzed, zero patellar and one Achilles tendon were transformed from "abnormal" to "normal"-this single tendon showed only a single neovessel without hypoechogenicity or thickening. Of all tendons initially categorized as "normal," only 4 patellar tendons switched categories to "abnormal" by the second scan, all with new hypoechogenic foci. Amongst these, all participants were asymptomatic. This prospective study demonstrated that all Achilles and patellar tendons with sonographic abnormalities remain abnormal after 1 year of training and competition, with the exception of a single neovessel on one Achilles tendon that disappeared. A small percentage of collegiate student-athletes developed new abnormalities over a year of practice and competition. This may refute the idea that tendinosis comes and goes in this athletic population, given the minimal change in categorization of participants from either category.