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Reduction Osteotomy vs Pie-Crust Technique as Possible Alternatives for Medial Release in Total Knee Arthroplasty and
Ji Hyun Ahn1, Tae Yeong Yang1, Jang Yun Lee1
1Department of Orthopedic Surgery, Dongguk University Ilsan Hospital, Goyang-si, Gyeonggi-do, Korea.
Background:
To compare the gap change between the pie-crust technique and reduction osteotomy to determine their effects on flexion and extension gaps and their success rates in achieving ligament balancing during total knee arthroplasty.
Methods:
In a prospective randomized controlled trial, 106 total knee arthroplasties were allocated to each group with 53 cases. If there was a narrow medial gap with an imbalance of ≥3 mm after the initial limited medial release, either reduction osteotomy or pie-crust technique was performed. The changes of extension and flexion medial gaps along with the success rate of mediolateral balancing were compared.
Results:
There was a significant difference in the change of medial gap in knee extension with mean changes of 3.5 ± 0.5 mm and 2.3 ± 0.8 mm in the reduction osteotomy and pie-crust groups, respectively (P < .001). For flexion gap, greater change was found in the pie-crust group compared with the reduction osteotomy group; the mean medial gap changes in knee flexion were 1.1 ± 0.5 mm and 2.3 ± 1.2 mm in the reduction osteotomy and pie-crust groups, respectively. The success rates were 90.6% and 67.9% in reduction osteotomy and pie-crust groups, respectively (P = .007).
Conclusion:
As an alternative medial release method, reduction osteotomy was more effective in extension gap balancing, and pie-crust technique was more effective in flexion gap balancing. The overall success rate of mediolateral ligament balancing was higher in the reduction osteotomy group than in the pie-crust group.
