Ou Deyan, Deng Gaoyong, Qin Gaosheng, Ye Yongqing, Pan Jingwei, Huang Yu, Kuang Haisheng, Tang Shilin, Mo Yongxin, Pan Shixin
Department of Limb and Joint Ward, Wuzhou Red Cross Hospital, Wuzhou, Guangxi Province, China.
Department of Spine Ward, Affiliated Hospital of Guilin Medical College, Guilin, Guangxi Province, China.
BMC Musculoskelet Disord. 2025 May 9;26(1):453. doi: 10.1186/s12891-025-08630-y.
Unicompartmental knee arthroplasty (UKA) has shown significant clinical effectiveness in treating medial compartment knee degeneration, but postoperative periprosthetic fractures and persistent pain remain common and challenging complications. Tibial vertical cutting errors are considered an important factor influencing postoperative biomechanics. This study aims to investigate the biomechanical effects of tibial vertical cutting errors(referring to the deviation between the actual vertical cutting plane and the ideal vertical resection plane during UKA)on the proximal tibia after UKA and to reduce the risk of fractures and improve postoperative outcomes through surface modification designs (chamfering and filleting).
In this study, a three-dimensional model of the tibia was constructed from CT and MRI data of a 26-year-old male volunteer. Finite element analysis (FEA) was used to simulate different vertical cutting errors (1 mm, 3 mm, 5 mm, 7 mm, and 9 mm). The study included models with varying cutting errors and two surface modification designs. During the simulation, stress and strain distribution on the proximal tibia were analyzed to assess the impact of cutting errors on the risk of periprosthetic fractures. Additionally, the fracture risk was quantified using the Risk of Fracture(ROF) index, and statistical data analysis and comparison were performed.
The results showed that as the vertical cutting error increased, the equivalent stress and fracture risk value beneath the tibial prosthesis significantly increased. Notably, in the 5-9 mm cutting error models, the fracture risk was markedly higher. The chamfering and rounding designs effectively reduced stress concentration beneath the tibial prosthesis, lowering the stress peaks and significantly decreasing the fracture risk. In the ROF calculation, when the vertical cutting error exceeded 5 mm, the ROF value significantly exceeded the critical value, indicating a substantial increase in fracture risk. Compared to the standard osteotomy method, both surface modification designs effectively reduced the fracture risk.
Tibial vertical cutting error is a significant risk factor for periprosthetic fractures and pain after UKA. The greater the vertical cutting error, the faster the fracture risk and bone degeneration progress. Specifically, when the vertical cutting error exceeds 5 mm, the fracture risk increases significantly. The surface modification design proposed in this study effectively mitigates the negative biomechanical effects of cutting errors on the tibia and reduces the risk of postoperative complications. Future research should further explore the impact of other factors, such as osteoporosis, activity level, and muscle strength, on UKA outcomes, and incorporate advanced surgical navigation technologies to improve surgical precision and reduce errors.
单髁膝关节置换术（UKA）在治疗膝关节内侧间室退变方面已显示出显著的临床疗效，但术后假体周围骨折和持续性疼痛仍然是常见且具有挑战性的并发症。胫骨垂直截骨误差被认为是影响术后生物力学的一个重要因素。本研究旨在探讨胫骨垂直截骨误差（指UKA手术过程中实际垂直截骨平面与理想垂直截骨平面之间的偏差）对UKA术后胫骨近端的生物力学影响，并通过表面改性设计（倒角和倒圆角）降低骨折风险，改善术后效果。
在本研究中，根据一名26岁男性志愿者的CT和MRI数据构建了胫骨的三维模型。采用有限元分析（FEA）模拟不同的垂直截骨误差（1毫米、3毫米、5毫米、7毫米和9毫米）。该研究包括具有不同截骨误差的模型以及两种表面改性设计。在模拟过程中，分析胫骨近端的应力和应变分布，以评估截骨误差对假体周围骨折风险的影响。此外，使用骨折风险（ROF）指数对骨折风险进行量化，并进行统计数据分析和比较。
结果表明，随着垂直截骨误差的增加，胫骨假体下方的等效应力和骨折风险值显著增加。值得注意的是，在截骨误差为5 - 9毫米的模型中，骨折风险明显更高。倒角和倒圆角设计有效地降低了胫骨假体下方的应力集中，降低了应力峰值，并显著降低了骨折风险。在ROF计算中，当垂直截骨误差超过5毫米时，ROF值显著超过临界值，表明骨折风险大幅增加。与标准截骨方法相比，两种表面改性设计均有效地降低了骨折风险。
胫骨垂直截骨误差是UKA术后假体周围骨折和疼痛的重要危险因素。垂直截骨误差越大，骨折风险和骨质退变进展越快。具体而言，当垂直截骨误差超过5毫米时，骨折风险显著增加。本研究提出的表面改性设计有效地减轻了截骨误差对胫骨的负面生物力学影响，并降低了术后并发症的风险。未来的研究应进一步探讨骨质疏松、活动水平和肌肉力量等其他因素对UKA手术效果的影响，并引入先进的手术导航技术以提高手术精度，减少误差。
