Abstract：
BACKGROUND: Achieving stability in total knee arthroplasty (TKA) is crucial for long-term implant survival. In cases of severe deformity or ligament laxity, constrained implants may be required. Traditionally, increasing constraint involved intramedullary stems. However, there are intermediary alternatives, including employing a constrained polyethylene insert without stems, thereby avoiding complications related to them. The study aims to evaluate our experience with a non-modular constrained (NMC) implant in primary TKA.
METHODS: We conducted a retrospective review of the clinical and radiographic outcomes of 108 non-stemmed primary TKAs performed at our institution between 2013 and 2021 in patients with at least 10° deformity or 10mm ligament laxity. Data included demographics, preoperative and postoperative deformities, clinical outcomes and revision rates.
RESULTS: A total of 103 patients (108 knees) with a mean age of 74 were followed up for a minimum of 2 years. The mean postoperative range of motion was 105°/0°. The median Oxford Knee Score, Knee Society Score and Knee Society Function Score were 43.5, 92 and 90, respectively. 17 knees had varus deformity (mean tibiofemoral angle of 2.7°), and 87 knees had excessive valgus deformity (mean tibiofemoral angle of 15.1°). The remaining 4 knees had a neutral alignment. The mean postoperative tibiofemoral angle was 6.8°. The overall revision rate was 6.5% (7 patients): 3 deep periprosthetic infections, 2 patellar dislocations, 1 stiffness and 1 aseptic loosening.
CONCLUSIONS: Our experience demonstrates favorable mid-term outcomes with the NMC implant, providing a safe alternative to stemmed implants in primary TKA, particularly in cases of severe deformity or ligament laxity.
METHODS: We conducted a retrospective review of the clinical and radiographic outcomes of 108 non-stemmed primary TKAs performed at our institution between 2013 and 2021 in patients with at least 10° deformity or 10mm ligament laxity. Data included demographics, preoperative and postoperative deformities, clinical outcomes and revision rates.
RESULTS: A total of 103 patients (108 knees) with a mean age of 74 were followed up for a minimum of 2 years. The mean postoperative range of motion was 105°/0°. The median Oxford Knee Score, Knee Society Score and Knee Society Function Score were 43.5, 92 and 90, respectively. 17 knees had varus deformity (mean tibiofemoral angle of 2.7°), and 87 knees had excessive valgus deformity (mean tibiofemoral angle of 15.1°). The remaining 4 knees had a neutral alignment. The mean postoperative tibiofemoral angle was 6.8°. The overall revision rate was 6.5% (7 patients): 3 deep periprosthetic infections, 2 patellar dislocations, 1 stiffness and 1 aseptic loosening.
CONCLUSIONS: Our experience demonstrates favorable mid-term outcomes with the NMC implant, providing a safe alternative to stemmed implants in primary TKA, particularly in cases of severe deformity or ligament laxity.
摘要：
背景：在全膝关节置换术（TKA）中实现稳定性对于植入物的长期存活至关重要。在严重畸形或韧带松弛的情况下，可能需要约束植入物。传统上,增加约束涉及髓内茎。然而,有中介选择，包括采用无杆的约束聚乙烯插入件，避免与之相关的并发症。该研究旨在评估我们在原发性TKA中使用非模块化约束（NMC）植入物的经验。
方法：我们对2013年至2021年间在我们机构进行的108例非茎性原发性TKAs的临床和影像学结果进行了回顾性回顾，这些患者至少有10º畸形或10mm韧带松弛。数据包括人口统计，术前和术后畸形，临床结果和修订率。
结果：共103例患者（108膝），平均年龄74岁，随访时间至少为2年。术后平均活动范围为105º/0º。牛津膝盖评分中位数,膝关节社会评分和膝关节社会功能评分分别为43.5、92和90。17个膝盖有内翻畸形（平均胫股角2.7º），87个膝盖有过度的外翻畸形（平均胫骨股角度为15.1º）。其余4个膝盖呈中性对齐。术后平均胫股角度为6.8º。总体翻修率为6.5%(7例):3例深部假体周围感染,2髌骨脱位,1刚度和1无菌性松动。
结论：我们的经验表明，NMC植入物的中期结局良好，为原发性TKA中的茎状植入物提供安全的替代方案，特别是在严重畸形或韧带松弛的情况下。
方法：我们对2013年至2021年间在我们机构进行的108例非茎性原发性TKAs的临床和影像学结果进行了回顾性回顾，这些患者至少有10º畸形或10mm韧带松弛。数据包括人口统计，术前和术后畸形，临床结果和修订率。
结果：共103例患者（108膝），平均年龄74岁，随访时间至少为2年。术后平均活动范围为105º/0º。牛津膝盖评分中位数,膝关节社会评分和膝关节社会功能评分分别为43.5、92和90。17个膝盖有内翻畸形（平均胫股角2.7º），87个膝盖有过度的外翻畸形（平均胫骨股角度为15.1º）。其余4个膝盖呈中性对齐。术后平均胫股角度为6.8º。总体翻修率为6.5%(7例):3例深部假体周围感染,2髌骨脱位,1刚度和1无菌性松动。
结论：我们的经验表明，NMC植入物的中期结局良好，为原发性TKA中的茎状植入物提供安全的替代方案，特别是在严重畸形或韧带松弛的情况下。
