Bioengineering Laboratory, Newton-Wellesley Hospital, Newton, MA, 02462, USA.
Sports Medicine Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA.
Knee Surg Sports Traumatol Arthrosc. 2019 Aug;27(8):2440-2449. doi: 10.1007/s00167-018-5233-7. Epub 2018 Oct 26.
To elucidate the effects of various tibial and femoral attachment locations on the theoretical length changes and isometry of PCL grafts in healthy knees during in vivo weightbearing motion.
The intact knees of 14 patients were imaged using a combined magnetic resonance and dual fluoroscopic imaging technique while the patient performed a quasi-static lunge (0°-120° of flexion). The theoretical end-to-end distances of the 3-dimensional wrapping paths between 165 femoral attachments, including the anatomic anterolateral bundle (ALB), central attachment and posteromedial bundle (PMB) of the PCL, connected to an anterolateral, central, and posteromedial tibial attachment were simulated and measured. A descriptive heatmap was created to demonstrate the length changes on the medial condyle and formal comparisons were made between the length changes of the anatomic PCL and most isometric grafts.
The most isometric graft, with approximately 3% length change between 0° and 120° of flexion, was located proximal to the anatomic femoral PCL attachments. Grafts with femoral attachments proximal to the isometric zone decreased in length with increasing flexion angles, whereas grafts with more distal attachments increased in length with increasing flexion angles. The ALB and central single-bundle graft demonstrated a significant elongation from 0° to 120° of flexion (p < 0.001). The PMB decreased in length between 0° and 60° of flexion after which the bundle increased in length to its maximum length at 120° (p < 0.001). No significant differences in length changes were found between either the ALB or PMB and the central graft, and between the ALB and PMB at flexion angles ≥ 60° (n.s.).
The most isometric attachment was proximal to the anatomic PCL footprint and resulted in non-physiological length changes. Moving the femoral attachment locations of the PCL significantly affected length change patterns, whereas moving the tibia locations did not. The importance of anatomically positioned (i.e., distal to the isometric area) femoral PCL reconstruction locations to replicate physiological length changes is highlighted. These data can be used to optimize tunnel positioning in either single- or double-bundle and primary or revision PCL reconstruction cases.
IV.
阐明在体内负重运动过程中，健康膝关节中各种胫骨和股骨附着位置对 PCL 移植物的理论长度变化和等距性的影响。
使用磁共振和双荧光透视成像技术联合对 14 例患者的完整膝关节进行成像，同时患者进行准静态弓步（0°-120°屈曲）。模拟并测量了连接到前外侧、中央和后内侧胫骨附着点的 165 个股骨附着点（包括 PCL 的解剖前外侧束[ALB]、中央附着点和后内侧束[PMB]）的三维包裹路径之间的理论端到端距离。创建了描述性热图以显示内侧髁上的长度变化，并对解剖 PCL 和最等距移植物的长度变化进行了正式比较。
在 0°至 120°屈曲之间具有约 3%长度变化的最等距移植物位于解剖股骨 PCL 附着点的近端。随着屈曲角度的增加，具有更靠近等距区的股骨附着点的移植物会缩短，而具有更远端附着点的移植物会随着屈曲角度的增加而变长。ALB 和中央单束移植物从 0°到 120°的屈曲显著延长（p < 0.001）。PMB 在 0°至 60°屈曲之间缩短，然后束在 120°时增加到最大长度（p < 0.001）。在 0°至 60°的屈曲角度内，ALB 或 PMB 和中央移植物之间以及 ALB 和 PMB 之间的长度变化没有差异（n.s.）。
最等距的附着点位于解剖 PCL 足迹的近端，导致非生理长度变化。移动 PCL 的股骨附着位置显著影响长度变化模式，而移动胫骨位置则没有。强调了在解剖上定位（即位于等距区远端）的股骨 PCL 重建位置对于复制生理长度变化的重要性。这些数据可用于优化单束或双束以及原发性或复发性 PCL 重建病例中的隧道定位。
IV。
