PURPOSE: This study aimed to characterize the anatomical features of the ankle flexor retinaculum and to provide a coordinate-based anatomical data on tibial nerve and posterior tibial artery branching points in Vietnamese cadaveric specimens. METHODS: A descriptive cadaveric study was conducted on 60 lower leg and foot specimens from Vietnamese adult cadavers preserved in formalin. Anatomical measurements were obtained using calibrated electronic calipers. The branching points of the tibial nerve and posterior tibial artery were mapped using an O-xy Cartesian coordinate system, with the medial malleolus serving as the reference landmark. RESULTS: The mean length of the medial malleolus-calcaneus axis was 66.3 ± 6.8 mm. Branching within the flexor retinaculum was observed in 76.7% of specimens for the tibial nerve and 100% for the posterior tibial artery. The mean coordinates of tibial nerve branching points were (26.8 ± 8.5; 16.4 ± 11.9), while those of the posterior tibial artery were (36.8 ± 6.1; -2.6 ± 8.6). Significant sex differences were identified in most anatomical measurements (p < 0.05). A branching-dense region was observed approximately 25-40 mm distal to the medial malleolus. CONCLUSION: This study provides coordinate-based anatomical data on neurovascular branching within the ankle flexor retinaculum in Vietnamese cadaveric specimens. The findings offer supplementary anatomical references for procedures around the medial ankle and should be interpreted together with individual anatomical variation and image-guided assessment when available.