Posterior Approach to the Knee

Cadaveric posterior approach to the knee, with an oblique incision near the posterior midline and the fascia opened to show the small saphen
Cadaveric posterior approach to the knee, with an oblique incision near the posterior midline and the fascia opened to show the small saphenous vein and medial sural cutaneous nerve. Image from Boluda-Mengod J, Olías-López B, Forcada-Calvet P, Martín-Herrero A, Herrera-Pérez M, Álvarez-De-La-Cruz J, Herrera-Rodríguez A, Pais-Brito JL. Modified Oblique Lobenhoffer (MOL) approach for posterolateral and posteromedial column access in tibial plateau fractures, a detailed cadaveric anatomical study. J Orthop Traumatol. 2024, 25(1), 27. CC BY 4.0.
Gray’s Anatomy illustration of the back of the knee joint
Right knee joint from behind. The posterior approach works through the popliteal fossa, where the tibial nerve and popliteal vessels lie over the joint capsule. Image by Henry Vandyke Carter, Gray’s Anatomy (1918), Wikimedia Commons, public domain.

Aims

  • Primarily a neurovascular approach

Position

  • prone
  • longitudinal bolsters to support chest & abdomen & allow expansion

Landmarks

  • 2 heads of gastrocnemius
  • semimembranosus & semitendinosus
  • biceps tendons

Incision

  • longitudinal gently curved incision
  • Start: laterally over the biceps femoris muscle
  • Obliquely across the popliteal fossa
  • End: over medial head of gastrocnemius & inferior over calf

Superficial Dissection

  • reflect the skin flaps
  • identify small saphenous vein & medial sural cutaneous nerve on its lateral side (branch of tibial nerve)
  • incise the fascia of popliteal fossa medial to small saphenous vein
  • trace the medial sural cutaneous nerve proximally back to its source
  • dissect up to the apex of the popliteal fossa following the tibial nerve
  • dissect the common peroneal nerve at the apex of the popliteal fossa
    • it runs along the posterior border of biceps femoris
  • identify the popliteal artery & vein
    • lies deep & medial to tibial nerve
    • artery has 5 branches
      • two superior
      • two inferior
      • one middle genicular artery
      • may need to be ligated to mobilise the artery
    • Distally
      • Vein is medial to artery
      • Then it moves posterior to artery
      • Then lies posterolateral to artery above the knee joint

Deep Dissection

  • Retract the muscles that form the boundaries of popliteal fossa to expose the various parts of posterior joint capsule
  • Can detach either medial or lateral heads of gastrocnemius

Dangers

Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.