TY - JOUR
T1 - In silico comparative biomechanical analysis of oblique and chevron medial displacement calcaneal osteotomies for pes planus deformity
AU - Subasi, Omer
AU - Sharma, Siddartha
AU - Karaismailoglu, Bedri
AU - Hresko, Andrew
AU - Waryasz, Gregory
AU - Ashkani-Esfahani, Soheil
AU - Bejarano-Pineda, Lorena
N1 - Publisher Copyright: © 2024 Elsevier Ltd
PY - 2024/2/1
Y1 - 2024/2/1
N2 - Background: Medializing displacement calcaneal osteotomy is commonly performed as part of reconstructive surgery for patients with valgus hindfoot and progressive pes planus deformity. Among several types of calcaneal osteotomies, the oblique and Chevron osteotomy patterns have been commonly described in the literature and gained popularity as they are easily reproducible through percutaneous techniques. Currently, there is scarce evidence in the literature on which cut pattern is superior in terms of stability. To investigate the impact of cut pattern and posterior fragment medialization level on foot biomechanics, computational methods are employed. Methods: Ankle weightbearing computer tomography (CT) scans of seven patients diagnosed with stage II pes planus deformity are segmented and converted into 3D computational models. Oblique and Chevron osteotomy patterns are modeled independently for each patient. The posterior fragments are medially translated by 8-, 10- and 12-mm and subsequently fixated to the anterior calcaneus with two screws. A total of 42 models are exported to finite element software for biomechanical simulations. Among the investigated parameters, the higher stiffness and lower von Mises stress at the osteotomy interface and the screw site are assumed to be precursors of better stability. Results: It is recorded that as the medialization level increases, the stiffness decreases, and overall stresses increase. Also, it is observed that the Chevron cut produces a stiffer construct while the overall stresses are lower, indicating better stability when compared to the oblique cut. The statistical comparisons of the relevant groups that support these trends are found to be significant (p < 0.05). Conclusion: Chevron osteotomy showed superior stability compared to the oblique osteotomy while underscoring the negative impact of increased medialization of the posterior fragment. Clinical relevance: Opting for a lower medialization level and implementing the Chevron technique may facilitate union and earlier weightbearing.
AB - Background: Medializing displacement calcaneal osteotomy is commonly performed as part of reconstructive surgery for patients with valgus hindfoot and progressive pes planus deformity. Among several types of calcaneal osteotomies, the oblique and Chevron osteotomy patterns have been commonly described in the literature and gained popularity as they are easily reproducible through percutaneous techniques. Currently, there is scarce evidence in the literature on which cut pattern is superior in terms of stability. To investigate the impact of cut pattern and posterior fragment medialization level on foot biomechanics, computational methods are employed. Methods: Ankle weightbearing computer tomography (CT) scans of seven patients diagnosed with stage II pes planus deformity are segmented and converted into 3D computational models. Oblique and Chevron osteotomy patterns are modeled independently for each patient. The posterior fragments are medially translated by 8-, 10- and 12-mm and subsequently fixated to the anterior calcaneus with two screws. A total of 42 models are exported to finite element software for biomechanical simulations. Among the investigated parameters, the higher stiffness and lower von Mises stress at the osteotomy interface and the screw site are assumed to be precursors of better stability. Results: It is recorded that as the medialization level increases, the stiffness decreases, and overall stresses increase. Also, it is observed that the Chevron cut produces a stiffer construct while the overall stresses are lower, indicating better stability when compared to the oblique cut. The statistical comparisons of the relevant groups that support these trends are found to be significant (p < 0.05). Conclusion: Chevron osteotomy showed superior stability compared to the oblique osteotomy while underscoring the negative impact of increased medialization of the posterior fragment. Clinical relevance: Opting for a lower medialization level and implementing the Chevron technique may facilitate union and earlier weightbearing.
KW - Finite element analysis
KW - Medializing displacement calcaneal osteotomy
KW - Pes planus deformity
KW - Weightbearing computed tomography
UR - http://www.scopus.com/inward/record.url?scp=85181777658&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.compbiomed.2024.107945
DO - https://doi.org/10.1016/j.compbiomed.2024.107945
M3 - Article
C2 - 38199207
SN - 0010-4825
VL - 169
JO - Computers in Biology and Medicine
JF - Computers in Biology and Medicine
M1 - 107945
ER -