Vascular anatomy of the patella: implications for total knee arthroplasty surgical approaches.

BACKGROUND: Iatrogenic disruption of the patellar vascular supply has been identified as a possible contributing factor to the commonly reported patellofemoral complications following total knee arthroplasty (TKA). We performed an anatomic cadaveric study evaluating the extra-osseous vascular anatomy of the patella, and correlated our findings to routine TKA surgical dissection to determine how to better preserve patellar vascularity. METHODS AND MATERIALS: In twenty-one cadaveric knees arterial cannulas were placed proximally and distally to the patella. A polyurethane compound was then injected producing a visible arterial network. Specimens underwent gross dissection.
RESULTS: In all 21 specimens, the supreme genicular (SGA), medial/lateral superior genicular (MSGA/LSGA), medial/lateral inferior genicular and anterior tibial recurrent arteries communicate forming a peripatellar anastomotic ring supplying the intraosseous patellar system. Both the SGA (24%) and MSGA (76%) demonstrated dual medial ring contribution. Relating the arterial location to common TKA exposures suggested severe compromise of patellar vascularity.
CONCLUSION: The medial sided vessels seem to contribute more significantly to the peripatellar anastomotic ring when compared to the lateral sided vessels. Careful soft tissue management has the potential to preserve key vascular structures that could maintain the intraosseous vascular supply to the patella. Understanding the anatomic locations of major arterial systems around the knee joint can potentially help during hemostasis, and can minimize blood loss during TKA. CLINICAL RELEVANCE: Recognition of major arterial systems around the knee joint has the potential to minimize iatrogenic disruption of the vascular supply and the complications that can follow (patella devascularization and blood lost).