- Approach to the anteromedial surface of the tibia
The anteromedial approach to the tibial shaft is through an incision placed just lateral to the anterior tibial crest.
Its most common use is for fractures of the distal third tibial shaft. However, it can be used to expose the entire anteromedial surface.
It is also useful for debridement and irrigation of open fractures when an incision on the injured subcutaneous surface is to be avoided.
Advantages of this approach are:
- It removes no muscle from the fracture fragments.
- The relatively simple shape of this surface makes plate contouring easy for conventional plates, and especially so for precontoured plates.
A significant disadvantage of this approach is, that it should not be used when the medial skin has a substantial contusion.
Triangular shape of the tibia
The lateral and posterior surfaces of the tibia are covered by muscle. The anteromedial surface has only a thin layer of subcutaneous tissue and skin. This surface provides less blood supply to the underlying bone.
The lower leg has four compartments:
- Deep posterior
- Superficial posterior
The anterior compartment has three muscles and one main artery and nerve: Tibialis anterior, extensor hallucis longus, extensor digitorum longus; the anterior tibial artery and deep peroneal nerve.
The lateral compartment has two muscles and one nerve. The muscles are the peroneus longus and brevis and the superficial peroneal nerve.
The deep posterior compartment has three muscles and two arteries and one nerve: The muscles are the tibialis posterior, the flexor hallucis longus and the flexor digitorum longus. It also has the peroneal artery and the posterior tibial artery as well as the tibial nerve.
The superficial posterior compartment has just two muscles in it: The gastrocnemis and soleus muscles and the sural nerve.
Approach the anteromedial surface through a longitudinal incision 1-2 cm lateral to the tibial crest. Distally, continue along the medial edge of the tibialis anterior in a gentle curve in the direction of the medial malleolus.
The deep dissection should stay superficial to the fascia layer of the anterior compartment.
The length of the incision depends on the planned plate length.
Take care not to compromise the saphenous vein and nerve, which are at risk at the distal extend of the approach.
Entrance into the anterior tibial tendon sheath should be avoided, as this can cause unwanted adhesions.
Full thickness skin and subcutaneous tissue flaps are then mobilized in a medial direction. In this way the anteromedial aspect of the tibia is directly exposed. The periosteum is left intact, or minimally reflected from the fracture edges, if necessary for a direct anatomical reduction.