Popliteal fascia

Fascia poplitea · Podkolenní povázka

Fascia & connective tissue

Looks like

The deep fascia covering the hollow behind the knee, continuous with the fascia of thigh and leg.

Roofs over the popliteal vessels and nerves.

Fluid-filled Baker's cysts bulge under it; a sudden painful calf swelling can be a burst cyst or a clot, needing a scan.