Anatomical Relationship of the Popliteal Artery to Tibial Landmarks at Resection Levels in Total Knee Arthroplasty: A Cadaver Study.

Abstract

Injury to the popliteal artery (PA) is a severe complication during total knee arthroplasty (TKA). Current information on the anatomical proximity of the PA to the posterior tibial cortex is mostly derived from imaging studies, which may not accurately represent surgical conditions. Additionally, anatomical differences between sexes remain unclear. This cadaver study aimed to determine the anatomical relationship between the PA and tibial landmarks at clinically relevant tibial resection levels during TKA, emphasizing potential sex-based differences. Overall, 102 knees from 51 formalin-embalmed cadavers (24 men, 27 women) were dissected. An Akagi line-based coordinate system defined the tibial landmarks, and three standard tibial resection levels employed in TKA (joint line, 10 mm distal, and 15 mm distal) were evaluated. The posterior, lateral, and shortest distances from the posterior tibial cortex to the PA were measured. Multivariate linear regression analyses that adjusted for lower leg length were used to assess sex-based anatomical differences. The PA progressively approached the posterior tibial cortex distally; the median shortest distances significantly decreased from 10.0 mm (joint line) to 5.0 mm (15 mm distal). After adjusting for lower leg length, multivariate linear regression analysis revealed men as independently associated with greater posterior (P = 0.043) and shortest (P = 0.045) distances only at the joint level. However, these sex-based differences were no longer significant at deeper resection levels. During TKA, the anatomical risk of PA injury significantly increases at deeper tibial resection levels. Although there are sex-based anatomical differences at the joint line, they disappear at clinically relevant distal resection levels, highlighting the need for careful surgical vigilance regardless of patient sex.