Altern Ther Health Med. 2024 Nov;30(11):72-78.
Maintaining the lower limb in a neutral posture following total knee arthroplasty (TKA) has long been a concept maintained by operators. This study aimed to investigate the relationship between changes in lower limb alignment and the dynamics of knee gait before and after TKA to understand the impact of alignment on gait better and offer a theoretical foundation for correcting lower limb alignment in TKA.
Our study included a group of 20 participants. The cohort consisted of 1 male and 19 females, 11 left and 9 right knees, ages 58 to 81. Using the Opti_Knee® Knee Motion Test System with infrared reflective markers and a high-speed camera, the step length and 6 degrees of freedom of the knee were recorded. Following that, we investigated the association between HKA angle and knee kinematic gait before and after surgery.
For preoperative HKA angles ranging from -28° to -3°, we observed increased step length, flexion-extension rotation, and varus-valgus rotation with an increase in HKA angle. Conversely, an increase in HKA angle from -3 ° to 15° corresponded with decreased step length, flexion-extension rotation, and varus-valgus rotation. An increase in HKA angle from 1° to 3° postoperatively increased step length, flexion-extension rotation, and varus-valgus rotation. In contrast, increasing the HKA angle from 3° to 5° resulted in less flexion-extension rotation. The flexion-extension rotation was at its maximum when the HKA angle was 3°. A 3° postoperative varus resulted in improved kinematic gait. Step length, varus-valgus rotation, and flexion-extension rotation increased with increasing HKA angle in the neutral alignment group. In contrast, the non-neutral alignment group exhibited decreased flexion-extension rotation as the HKA angle increased, while step length and varus-valgus rotation increased as the HKA angle increased. The varus-valgus rotation was statistically significant (P < .05) in the preoperative versus early postoperative period in the 6 degrees of freedom.
A 3° varus alignment was found to have a superior postoperative knee kinematic gait, implying that a 3° varus alignment may be more suitable as a new gold standard for TKA than the traditional "0°" alignment. The neutral alignment group demonstrated a better knee kinematic gait than the non-neutral alignment group. During early postoperative walking, significant improvements in varus-valgus rotation were found in the 6 degrees of knee freedom.
全膝关节置换术（TKA）后保持下肢中立位一直是术者所坚持的理念。本研究旨在探讨 TKA 前后下肢对线变化与膝关节步态动力学的关系，更好地了解对线对线对步态的影响，并为 TKA 下肢对线的矫正提供理论依据。
本研究纳入 20 名参与者。该队列包括 1 名男性和 19 名女性，11 例左膝和 9 例右膝，年龄 58 至 81 岁。使用 Opti_Knee®膝关节运动测试系统，通过红外线反射标记和高速摄像机记录步长和膝关节的 6 个自由度。之后，我们研究了术前和术后 HKA 角与膝关节运动学步态之间的关系。
对于术前 HKA 角在-28°至-3°范围内，我们观察到 HKA 角增加时步长、屈伸旋转和内外翻旋转增加。相反，HKA 角从-3°增加到 15°时，步长、屈伸旋转和内外翻旋转减少。术后 HKA 角从 1°增加到 3°时，步长、屈伸旋转和内外翻旋转增加。相反，HKA 角从 3°增加到 5°时，屈伸旋转减少。HKA 角为 3°时，屈伸旋转达到最大。术后 3°的内翻改善了运动学步态。中立对线组中，随着 HKA 角的增加，步长、内外翻旋转和屈伸旋转增加。相反，非中立对线组中，随着 HKA 角的增加，屈伸旋转减少，而步长和内外翻旋转随着 HKA 角的增加而增加。术前与术后早期的 6 自由度比较，内外翻旋转具有统计学意义（P<.05）。
术后 3°的内翻对线显示出更好的膝关节运动学步态，这意味着 3°的内翻对线可能比传统的“0°”对线更适合作为 TKA 的新金标准。中立对线组的膝关节运动学步态优于非中立对线组。在术后早期行走时，膝关节 6 自由度的内外翻旋转明显改善。
