Posterior Approach To Knee Joint
-
The posterior approach to knee joint is neurovascular approach primarily.
- It’s rarely is needed by orthopedic surgeon because the medial and lateral approaches each provide good access to half the posterior capsule.
- The posterior approach to knee joint uses include:
- Repair of the neurovascular structures in the popliteal fossa.
- Repair of avulsion fractures of the posterior cruciate ligament (it’s insertion to the tibia).
- Recession of gastrocnemius muscle heads in cases of contracture.
- Lengthening of hamstring tendons.
- Excision of Baker’s cyst and other popliteal cysts.
- Access to the posterior capsule of the knee .
- Repair of the neurovascular structures in the popliteal fossa.
- Prone positioning is necessary in this approach.
- Slightly flex knee via a bump under the ankle.
- Landmarks:
- Gastrocnemius muscle.
- Semimembranosus and semitendinosus
muscles.
- Incision:
- Inverted L-shaped incision is made:
- Horizontal limb is in Langer’s lines in the popliteal space.
- Vertical limb begins at the medial corner of the popliteal fossa and extends distally.
- S-curve incision:
- Incision can be extended proximally on the lateral side for more extensile exposure.
- Inverted L-shaped incision is made:
- There is No true internervous or intermuscular plane for the posterior approach to knee joint.
- Dissection is maintained underneath the gastrocnemius muscle belly.
- Full thickness fasciocutaneous flaps are created.
- Sural nerve and short saphenous vein should be protected.
- Tendon of the gastrocnemius is seen and the muscle is retracted laterally:
- the posterior aspect of the knee capsule is then seen.
- Popliteus and soleus are subperiosteally elevated off the posterior tibia:
- this exposes almost all of the posterior tibia.
- If additional medial access is necessary, the medial head of the gastrocnemius can be released.
- Posterolateral extension should be limited due to risk of common peroneal nerve injury.
- The structures at risk during the posterior approach to knee joint includes:
- Popliteal artery:
- Risk is minimized with maintenance of access under the gastrocnemius muscle.
- Tibial nerve:
- Risk is minimized with maintenance of access under the gastrocnemius muscle.
- Sural nerve and short saphenous vein.
- Popliteal artery:
- Surgical Exposures in Orthopaedics book - 4th Edition
- Campbel's Operative Orthopaedics book 12th