2023 ISAKOS Biennial Congress ePoster
Reliability of Preoperative Planning Method That Considers Latent Medial Joint Laxity In Medial Open-Wedge Proximal Tibial Osteotomy
Dong Jin Ryu, MD, PhD., Seoul KOREA, REPUBLIC OF
Sung-Sahn Lee, MD., PhD., Goyangsi, Gyeonggido KOREA, REPUBLIC OF
Eui Yub Jung, MD, Seoul KOREA, REPUBLIC OF
Joon Ho Wang, MD, PhD, Seoul KOREA, REPUBLIC OF
Samsung medical cnter, Seoul, Seoul, KOREA, REPUBLIC OF
FDA Status Cleared
Summary
preoperative HTO planning considering the medial joint laxity
ePosters will be available shortly before Congress
Abstract
Background
Soft tissue laxity around the knee joint has been recognized as a crucial factor affecting correction error during medial open-wedge proximal tibial osteotomy (MOWPTO). Medial laxity in particular, which represents the changes in joint-line convergence angle (JLCA), affects soft tissue correction. The purpose of this study was to quantify medial laxity and develop a preoperative planning method that considers medial laxity.
Methods
This study retrospectively reviewed 139 knees in 117 patients who underwent navigation-assisted MOWPTO from January 2014 to July 2019 for symptomatic medial compartment osteoarthritis with varus alignment >5.We compared the results of 2 preoperative planning methods: conventional Miniaci (n ¼ 47) and latent medial laxity reduction (LMLR) (n ¼ 92). We evaluated the incidence of under-correction, acceptable correction, and overcorrection. The radiologic parameters were analyzed using multiple linear regression with a stepwise selection model to establish an equation for the optimal preoperative planning method. The intraclass correlation coefficients (ICCs) of intraobserver, interobserver, and inter-method reliability were calculated.
Results
The Miniaci method showed a higher incidence of over-correction (55.3%) than the latent medial laxity reduction method (22.8%) at postoperative 6 months (p=0.0006). The multiple linear regression with a stepwise selection model revealed a high correlation coefficient for the following equation: adjusted preoperative planning correction angle = 0.596 + 0.891 x target correction angle (TCA) - 0.255 x ?JLCA valgus (R2 = 0.888). On simplifying, target correction angle (TCA) – 1/3?JLCA valgus showed the highest inter-method (ICC) value (0.991) with the proposed equation. While, the Miniaci method showed a relatively low ICC value of 0.875.
Conclusion
The Conventional Miniaci method has a risk of over-correction after MOWPTO. An equation that is considering medial laxity could help to set a preoperative planning for optimal correction during MOWPTO.