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Chapter 66 Supramalleolar Osteotomy with Internal Fixation: Perspective 2

T E C H N I Q U E S

of the osteotomy, periosteal stripping should be limited to the osteotomy site. ■ The osteotomy is carried out as described in the section entitled Tibial Osteotomy. Medial Approach ■ The patient is positioned supine on the operating table; a bump placed under the contralateral hip may improve exposure. ■ The limb is exsanguinated and the tourniquet is inflated. ■ The great saphenous vein and the saphenous nerve usually lie anterior to the incision. A 10-cm longitudinal incision is made beginning over the medial malleolus and extending proximally over the distal tibia ( TECH FIG 6A ). ■ The skin flaps are mobilized, with care taken not to damage the neurovascular bundle, which runs along the anterior border of the medial malleolus ( TECH FIG 6B ). ■ The posterior tibial tendon, which lies immediately on the pos- terior aspect of the medial malleolus, must be identified and retracted posteriorly. It needs to be exposed, its sheath incised, and the tendon retracted posteriorly to visualize the dorsal sur- face of the distal tibia. Tibial Osteotomy ■ The tibia is exposed with minimal periosteal stripping ( TECH FIG 7A ). ■ The plane of the osteotomy is determined under image inten- sification, and a K-wire is placed from the medial cortex into the physeal scar or, in case of a malunion, at the apex of the deformation ( TECH FIG 7B ). ■ The periosteum is then incised at the level of the osteotomy and elevated off the bone using a scalpel or a periosteal elevator. The osteotomy must be planned carefully because placing it

TECH FIG 5 ● Anterior approach to the distal tibia with the interval between the extensor hallucis longus and the anterior tibial tendon and the neurovascular bundle lying lateral to it.

■ The deep neurovascular bundle (anterior tibial artery and deep peroneal nerve), located in the lateral aspect of the approach, must be identified and protected. ■ The ankle joint is covered by an extensive fat pad that contains a venous plexus and requires partial cauterization. ■ If tibiotalar joint débridement or exostectomy is required, we make an anterior capsulotomy at this time. If only a supramalleolar oste- otomy is planned, however, there is no need to expose the joint. ■ With all soft tissues and neurovascular structures protected, the anterior surface of the tibia can be exposed. To promote healing

A

B

TECH FIG 6 ● A,B. Medial approach to the distal tibia.