Patellar Tendinitis on MRI: Imaging Findings

Common Symptoms

• Activity-related anterior knee pain just below the kneecap
• Tenderness at the inferior pole of the patella on palpation
• Pain that worsens with jumping, sprinting, or squatting
• Stiffness at the start of activity that improves with warm-up
• Visible or palpable thickening of the patellar tendon

What We Look For on Imaging

• Thickening of the proximal patellar tendon on sagittal MRI
• Increased signal intensity within the tendon on T2-weighted and STIR sequences
• Focal or diffuse areas of mucoid degeneration within the tendon
• Partial thickness tears at the deep posterior fibers of the tendon origin
• Edema in the infrapatellar fat pad (Hoffa fat pad)
• Bone marrow edema at the inferior pole of the patella

Sources

1. Khan KM, Bonar F, Desmond PM, et al. Patellar tendinosis (jumper's knee): findings at histopathologic examination, US, and MR imaging. Victorian Institute of Sport Tendon Study Group. Radiology. 1996;200(3):821-827.
2. Visentini PJ, Khan KM, Cook JL, et al. The VISA score: an index of severity of symptoms in patients with jumper's knee (patellar tendinosis). Victorian Institute of Sport Tendon Study Group. J Sci Med Sport. 1998;1(1):22-28.
3. Lian OB, Engebretsen L, Bahr R. Prevalence of jumper's knee among elite athletes from different sports: a cross-sectional study. Am J Sports Med. 2005;33(4):561-567.
4. Malliaras P, Cook J, Purdam C, Rio E. Patellar tendinopathy: clinical diagnosis, load management, and advice for challenging case presentations. J Orthop Sports Phys Ther. 2015;45(11):887-898.