Krackow Suture Technique Effect on Patella Tendon Vascularity: Quantitative MRI Analysis

To assess the effects of Krackow suture technique on the vascularity of the patellar tendon.

Six fresh-frozen matched pair cadaveric knee specimens were used. The superficial femoral arteries were cannulated in all knees. The experimental knee underwent an anterior approach, patellar tendon transection from the inferior pole of the patella, 4-strand Krackow stitch placement, patellar tendon repair via 3-bone tunnels, and standard skin closure. The control knee underwent the identical procedure without Krackow stitching. All specimens then underwent precontrast and postcontrast enhanced quantitative magnetic resonance imaging assessment (with gadolinium-based contrast agent). Region of interest analysis was performed to assess for variation in signal enhancement between the experimental and control limbs in various patellar tendon regions and subregions. Latex infusion and anatomical dissection were performed to further evaluate vessel integrity and assess extrinsic vascularity.

Quantitative magnetic resonance imaging analysis demonstrated no statistically significant difference in overall arterial contributions. A small but nonsignificant decrease of 7.5% (SD ± 7.1%) in arterial contributions to the entire tendon was observed. Small nonstatistically significant regional decreases throughout the tendon were also detected. In the regional analysis, the largest to smallest decreases in arterial contributions after suture placement were found in the inferomedial, superolateral, lateral, and inferior tendon subregions. In the anatomical dissection, nutrient branches were seen dorsally and posteroinferiorly.

The vascularity of the patellar tendon was not significantly affected by Krackow suture placement. Analysis demonstrated small and not statistically significant decreases in arterial contributions, suggesting this technique does not significantly compromise arterial perfusion.