Table 2.

The five Vendittoli’s restricted kinematic alignment principles

Principle	Description
1	HKA limits ± 3° Arithmetic combination of LDFA and MPTA should be ± 3°
2	Joint obliquity limits to 5° LDFA and MPTA maximum 85–95°
3	Restore native ligament laxities No ligamentous releases should be performed unless anatomical bone adjustments are required by the protocol boundaries. Ligamentous releases are usually required with anatomical corrections > 3 degrees
4	Adjust the most contributing bone to the alignment deviation but favour femoral anatomy preservation (see Fig. 2)
5	Resurface the intact compartment (remove a bone and cartilage thickness equivalent to the implant thickness) and adjust the opposite compartment resection thickness Varus = lateral pivot point Valgus = medial pivot point

LDFA lateral distal femoral angle (mechanical), MPTA medial proximal tibial angle (mechanical), HKA arithmetic mechanical hip–knee–ankle angle (LDFA + MPTA)