Posterior approach to knee

Introduction

Describe indications and point out major advantages or disadvantages of approach

Position of patient

Prone on bolsters for chest.

Landmarks and incision

Along lateral side of biceps femoris, curvilinear across popilteal fossa, down medial gastrocnemius

Internervous plane

Insert description

Superficial dissection

Identify Medial Sural Cutaneous nerve (and short saphenous vein) inferiorly

Follow this superiorly incising fascia to apex of popilteal fossa [distal to proximal]

Deep dissection

Apex bounded by semimembranosus medially & biceps femoris laterally

Identify & protect common peroneal nerve starting at apex under biceps femoris and going distally [proximal to distal]

Identify tibial nerve, popliteal vessels deep at apex

5 branches of artery (2 superior, 2 inferior, 1 medial geniculate) – may have to ligate some for access

Posterolateral Corner

• Incise tendinous lateral head of gastrox off femoral condyle & retract it inferomedially
• Neurovascular bundle goes under & is protected by lateral head of gastrocnemius

Posteromedial Corner

• Incise tendinous medial head of gastrox off femoral condyle & retract it inferolaterally
• Neurovascular bundle goes under & is protected by medial head of gastrocnemius

Dangers

Insert description

How to enlarge the approach

Insert description

Keys

Medial sural cutaneous nerve superficially leads into popilteal fossa (distal to proximal)


Common peroneal nerve under biceps femoris (proximal to distal)


Identify +/- ligate neurovascular bundle proximally & deep


Take down either head of gastrocnemius for access to that corner