OrthoNet

High Tibial Osteotomy - Complications

Undercorrection - the most common complication
- basically, anything less than 7 degrees of valgus is undercorrected. Must get them to 8-10 degrees of valgus (representing an overcorrection of 3-5 degrees from normal valgus)

Overcorrection - second most common complication
- going too far is bad also; > 15 degrees of valgus is poorly tolerated and can cause patellofemoral tracking problems

Deep Peroneal Nerve Injury - third most common, but most dreaded complication
- caused by tight post-op bandages, tight casts, transient anterior compartment syndrome, and direct injury
- in general, it is not recommended to go expose it - just keep the knee flexed during the procedure; exposing it and even gentle handling of it can cause a neuropraxia.
- 0-40 mm from tip is where the motor branch to tibialis anterior arises
- 68-153 mm from tip is where motor branch to EHL arises - EHL weakness postop is frequently seen because of failure to recognize this. The safe zone is 160 mm from tip of fibula.

Vascular Injury & Compartment Syndrome
- do prophylactic fasciotomy and use drain if necessary

Delayed Union/Nonunion
- preserve the medial osseoperiosteal hinge! It is critical to stability of the osteotomy.
- osteotomy proximal to the tibial tubercle has a lower rate of nonunion than distal