Syntax

Syntactic actants

Actant 1: whose ankle it is
(a) Genitive
(b) Possessive
Лодыжки Маши были закрыты. Masha's ankles were covered.
Он смотрел на её узкие лодыжки. He looked at her narrow ankles.
NB When the word лодыжка functions as a subject and does not have a descriptive modifier, the construction лодыжка у + Genitive is often preferred to (a) and (b), above:
Лодыжки у Маши были узкие, изящные. Masha had slender, graceful ankles.

Restrictive modifiers

(a) adjectival modifier
(b) noun phrase: Adj + Genitive of нога
(c) prepositional phrase: на + Adj + Prepositional of нога
NB Note that (a) is more common than (b) or (c).
левая/правая лодыжка the left/right ankle
Правая лодыжка у Маши была расцарапана. Masha's right ankle was scratched.
лодыжка левой/правой ноги the left/right ankle
лодыжка на левой/правой ноге the left/right ankle