High tibial osteotomy (HTO) is a relatively conservative
surgical option in the management of medial knee pain.
Thus far, the outcomes have been variable, and apparently
worse than the arthroplasty alternatives when judged
using conventional metrics, owing in large part to uncer
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tainty around the extent of the correction planned and
achieved.

This review paper introduces the concept of detailed 3D
planning of the procedure, and describes the 3D printing
technology that enables the plan to be performed.

The different ways that the osteotomy can be undertaken,
and the varying guide designs that enable accurate regis
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tration are discussed and described. The system accuracy
is reported.

In keeping with other assistive technologies, 3D printing
enables the surgeon to achieve a preoperative plan with a
degree of accuracy that is not possible using conventional
instruments. With the advent of low dose CT, it has been
possible to confirm that the procedure has been under
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taken accurately too.

HTO is the ‘ultimate’ personal intervention: the amount of
correction needed for optimal offloading is not yet com
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pletely understood.

For the athletic person with early medial joint line over
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load who still runs and enjoys life, HTO using 3D printing
is an attractive option. The clinical effectiveness remains
unproven.