Surgery for severe equine cavo-varus is complex and must be individualized. The interindividual phenotypic variability demands a personalized planning of each foot to be operated. The study's primary goal was to evaluate the function and satisfaction of a series of patients with severe equinus cavo-varus deformity who underwent a triplanar tarsectomy and transposition of the posterior tibial tendon in a single stage surgery after a patient specific 3D biomodel planning. A series of 12 feet (5 patients bilaterally) operated with this technique was analyzed. The cohort comprised 2 females (28.5 %) and 5 males (71.4 %). The median follow-up time was 38.5 months (interquartile range: 24.75–48.75). The Foot and Ankle Disability Index pre (median 32.85; interquartile range: 20–46) and postsurgery (median 72; interquartile range: 56–75.5) were collected and statistically significant differences were observed (p < 0.002). Furthermore, the main variable evaluated was obtaining a plantigrade stable foot. This was clinically evaluated and was achieved in all patients except 1 patient who presented a residual equinus of 5º. This study shows that triplanar tarsectomy and posterior tibial tendon transfer in a single surgical procedure after patient-specific 3D biomodel planning allows for improved function in patients with severe equinus cavus varus foot deformity.