Patellar tendons with normal imaging and pain: change in imaging and pain status over a volleyball season.

OBJECTIVE: Patellar tendon injury commonly presents as abnormal imaging with pain or abnormal imaging without pain. Normal imaging with pain has also been reported clinically, but little is known about the behavior of these tendons over time. This study investigated the behavior of tendons with normal imaging and pain over a volleyball season.
DESIGN: Prospective study.
SETTING: Institutional. PARTICIPANTS: One hundred and one male and female volleyball players. MAIN OUTCOME MEASUREMENTS: At the beginning and end of the season ultrasound determined imaging status and the single leg decline squat test determined pain. The imaging and pain status at follow-up of tendons with normal imaging and pain at baseline was reported and contrasted to the imaging and pain status of the other patellar tendon injuries.
RESULTS: Tendons with normal imaging and pain [relative risk (RR) 15.1], abnormal imaging without pain (RR 14.6), and abnormal imaging with pain (RR 51.5) had a greater risk of having abnormal imaging with pain at the end of the season when compared with normal tendons (P < 0.01). Among tendons with normal imaging and pain at baseline, 27% had abnormal imaging without pain and 21% contained abnormal imaging with pain at the end of the season.
CONCLUSIONS: Patellar tendons with normal imaging and pain at the beginning of a volleyball season are equally as likely to have abnormal imaging and pain at the end of the season as tendons with abnormal imaging without pain. Normal imaging with pain may represent a clinically relevant patellar tendon injury.