Greater medial arterial supply revealed by 7-Tesla quantitative magnetic resonance imaging, histology and high-resolution computed tomography of the patellar tendon.
Academic Article
Overview
abstract
PURPOSE: To quantitatively assess relative arterial contributions to the patellar tendon (PT) across predefined anatomic regions with 7-Tesla quantitative magnetic resonance imaging (7T-qMRI), algorithm-based histological analysis and high-resolution computed tomography (micro-CT) in a cadaveric model. METHODS: Seven fresh-frozen human cadaveric knee pairs (mean age 41.9 ± 15.5 years) underwent limited vascular dissection and arterial cannulation. Pre- and post-contrast 7T-qMRI, with a volumetric interpolated breath-hold examination (VIBE) three-dimensional T1-weighted gradient echo pulse sequence, quantified tendonous vascularity by measuring contrast enhancement. Subsequent quantitative algorithm-based histologic analysis with hematoxylin and eosin (H&E) staining followed, and two additional specimens underwent high-resolution (98 μm) micro-CT for qualitative vascular assessment. RESULTS: In the transverse analysis, 7T-qMRI demonstrated the highest mean relative arterial contributions in the medial region (42.4%) compared with the middle region (30.2%; p = 0.035) and higher, though not significant, than the lateral region (32.0%). The central PT demonstrated greater relative arterial contributions (37.5%) than the proximal (26.5%) or distal (29.3%) thirds (p > 0.05) in the longitudinal analysis. At the patellar enthesis, the middle third exhibited higher contributions (35.3%) than medial (28.8%) or lateral (29.6%), without significance, while the tibial tuberosity showed greater contributions along the lateral region (37.2%; p > 0.05). Histology confirmed significantly greater medial arterial contribution, with 8.3% higher supply than lateral (p = 0.018). Micro-CT revealed a robust vascular network along the medial PT with smaller branches laterally. Distal to the inferior patellar pole, a peripatellar circular network, extending medially into the posterior PT layers, was qualitatively identified. CONCLUSION: 7T-qMRI and histological analyses demonstrated significantly greater arterial supply along the medial border of the PT, while micro-CT revealed a medial and peripatellar circular vascular network extending from the medial margin and the inferior patellar pole into the posterior tendon layers. These findings identify the medial margin as the main vascular source for the PT, with implications for surgical preservation and reducing PT devascularization risk. LEVEL OF EVIDENCE: N/A.
