2015 ISAKOS Biennial Congress ePoster #1727

Accuracy of Correction in Medial Opening Wedge High Tibial Osteotomy Using the Miniaci Method

Helen Vint, MBChB, MRCS, Carlisle UNITED KINGDOM
David W. Elson, MBChB, MRCS, FRCS (T&O), Newcastle upon Tyne, Tyne & Wear UNITED KINGDOM
Sean M. Phelan, MB BS FRCS (Tr & Orth), Carlisle UNITED KINGDOM
Paul Middleton, MBChB, MRCS, Carlisle UNITED KINGDOM
Matt James Dawson, FRCS, Carlisle UNITED KINGDOM

Cumberland Infirmary , Carlisle, Cumbria, UNITED KINGDOM

FDA Status Not Applicable

Summary: This study quantifies the correction accuracy using Miniaci’s method when surgically applied to HTO




High tibial osteotomy (HTO) is performed for medial compartment arthritis with varus malalignment. Modern plating techniques are stable enough to support a medial opening wedge where the osteotomy gap can be adjusted easily, during the procedure. Pre-operative planning with long leg alignment radiographs is mandatory. The reliability of Miniaci’s planning method is high and comparible to digital planning software, without the expense. However the accuracy of this technique beyond the planning stage is unknown. This study aims to quantify accuracy by comparing the intended and achieved correction.


The lead surgeon routinely records alignment parameters for HTO patients before and after surgery. Various factors will influence the intended correction which is usually aimed between neutral (50%) and Fujisawa’s point (62%) according to where the Mikulicz’ weight bearing line intersects the tibial width. HTO was performed according to the correction angles and opening distances generated from Miniaci’s method of pre-operative planning. The achieved correction was judged from radiographs performed three months after surgery. Comparison is made between the intended and achieved correction.


100 patients undergoing HTO were included. The achieved correction ranged from 30.6% to 81.3% (mean of 60.4%). 30 patients were within 5% of the predicted correction, 40 patients were within 5-10%, 17 patients within 10-15%,12 patients within 15-20% and 1 patient within 20-30%. 53 were corrected positively with 47 corrected negatively.


This is the first study to quantify the surgical accuracy of corrections using Miniaci’s method. The majority (70.0%) were corrected to within 10% of that intended, 99% of patients were corrected to within 20%. This study should serve as a benchmark when compared to other methods for planning HTO.