Posterior Approach to the Knee (Step by Step Surgical Tech with Images)
Position of the Patient
Position the patient prone on the operating table and use a tourniquet for all procedures except vascular repairs.
Palpation of the Gastrocnemius Muscle Heads
Palpate the two heads of the gastrocnemius muscle at their origin on the posterior femoral surface just above the medial and lateral condyles.
Curved Incision over the Popliteal Fossa
Make a gently curved incision starting laterally over the biceps femoris muscle, obliquely across the popliteal fossa, and downward over the medial head of the gastrocnemius muscle into the calf.
Incising the Fascia of the Popliteal Fossa
Incise the fascia of the popliteal fossa just medial to the small saphenous vein and trace the medial sural cutaneous nerve proximally back to its source, the tibial nerve. Dissect up to the apex of the popliteal fossa while following the tibial nerve.
Detaching the Tendinous Origin of the Medial Head of the Gastrocnemius Muscle
Retract the muscles that form the boundaries of the popliteal fossa to expose various parts of the posterior joint capsule. Detach the tendinous origin of the medial head of the gastrocnemius muscle from the back of the femur to expose the posteromedial portion of the joint capsule.
Detaching the Origin of the Lateral Head of the Gastrocnemius Muscle
Retract the muscles that form the boundaries of the popliteal fossa to expose various parts of the posterior joint capsule. Detach the origin of the lateral head of the gastrocnemius muscle from the lateral femoral condyle to expose the posterolateral corner of the joint capsule.
Detaching the Heads of the Gastrocnemius Muscle
If needed, detach one or both of the heads of the gastrocnemius muscle to expose the knee capsule itself.
Extending the Approach Inferiorly
To extend the approach inferiorly, expose the trifurcation of the popliteal artery and trace the anterior tibial artery above the upper border of the interosseous membrane into the extensor compartment of the leg tethering the artery.