WESTERN Bulldogs AFLW captain Katie Brennan's post-season surgery is more extensive than first thought, with the forward having undergone a reconstruction on her right ankle two weeks ago.

Brennan, who has had ankle injuries in the past, missed four weeks of the just-completed NAB AFL Women's season with ligament damage.

She returned for round seven but was clearly hindered, playing with an ankle brace, before missing the Grand Final triumph through suspension.

The 25-year-old needed a regraft of her ankle bone, with ligaments then reattached on both the medial (inside) and lateral (outside) sides of the ankle.

She is expected to miss the majority of the upcoming VFLW season, with the Bulldogs hoping she will be fully fit for 2019 AFLW season.

Brennan was the equal-leading goal-kicker in last year's VFLW competition, playing for Darebin.