Anatomical Definition
The popliteal fossa (also known as the popliteal space) is the anatomical region located behind the knee joint 2. This diamond-shaped depression serves as a critical anatomical junction containing important neurovascular structures 3, 2.
Clinical Significance
Key Anatomical Contents
The popliteal fossa contains several vital structures that make it clinically important 3:
- Popliteal artery - the major arterial supply to the lower leg 1
- Popliteal vein - the primary venous drainage 4
- Tibial nerve and common peroneal nerve - critical neural structures 1, 3
- Popliteal lymph nodes - part of the lymphatic drainage system 1
Common Clinical Pathology
The popliteal fossa is a site where multiple pathological conditions can develop 2, 5:
- Baker's cysts (popliteal cysts) - fluid accumulations in the gastrocnemius or semimembranosus bursa that appear as comma-shaped extensions between the medial head of gastrocnemius and semimembranosus tendon 1, 6
- Popliteal artery aneurysms - require ultrasound evaluation when a palpable mass is detected 7, 6
- Deep vein thrombosis - diagnosed by compression ultrasonography from the common femoral vein to the popliteal vein at the popliteal fossa 1
- Vascular injuries - particularly following posterior knee dislocation, where approximately 30% of patients may have popliteal artery injury 1
Anatomical Boundaries
The popliteal fossa can be defined by reliable bony landmarks 4: