关节镜下前交叉韧带股骨止点定位新方法的研究

A novel method to pinpoint the femoral foot-print of the anterior cruciate ligament

目的探讨一种新的前交叉韧带（ACL）股骨止点定位方法，以期为临床关节镜下ACL重建术中的股骨骨隧道的定位提供依据。方法选取69名志愿者，男50名，女19名；年龄14～57岁，平均29．1岁。采用双源CT及其工作站建立膝关节股骨外髁内侧壁三维模型，圈画ACL股骨止点足迹、标记Blumensaat线、定位股骨远端与股骨滑车相交点（O点）。根据ACL股骨足迹形态，分为单束重建与双束重建。分别测量O点至ACL．股骨止点中心点的距离及其连线与B｜umensaat线的央角（∠1），O点至ACL前内侧柬中心点的距离及其连线与Blumensaat线的夹角（∠2），O点至ACL后外侧束中点的距离及其连线与Blumensaat线的夹角（∠3）。按照上述方法初步对10例ACL损伤患者进行测量，并根据测量结果在ACL重建术中进行股骨骨隧道的建立，术后再次利用双源CT扫描，评估术前定位与术后骨隧道位置的一致性。结果志愿者中适合单束重建37膝，O点至ACL股骨止点印迹中心的距离平均为1．24cm，／1平均为43．4°。适合双束重建32膝，O点至前内侧柬印迹中心的距离平均为0．90cm，∠2平均为44．5°；0点至后外侧束印迹中心的距离平均为1．48cm，∠3平均为47．9°。10例ACL重建患者术后双源CT扫描发现该定位方法有较高的准确性和良好的可重复性。结论本研究基于双源CT所开发的股骨止点定位新方法能够精确定位ACL股骨足迹，根据足迹可在术前规划中选择单束或双束重建ACL，对ACL重建术中的关节镜下股骨骨隧道定位及实现个体化股骨骨隧道的解剖重建有一定指导意义。

Objective To explore a new method to pinpoint the femoral foot-print of the anterior cruciate ligament （ACL） . Methods Enrolled in this study were 69 volunteers, 50 men and 19 women with an average age of 29. 1 years. Three-dimensional （3D） models of the internal wall of the lateral femoral condyle were reconstructed using a dual-source CT scanner and its workstation. The femoral foot-print of ACL was outlined on the images and the Blumensaat line was also drawn. The turning point from the posterior cartilage of the lateral femoral condyle to the posterior femoral metaphysis was defined as point O. Single- or double-bundle reconstruction pattern was determined in the volunteers according to their foot-print shape. The distance from point O to the single-bundle center and the angle between the Blumensaat line and the line from point O to the foot-print center （∠1）, the distance from point O to the anteromedial bundle center and the angle between the Blumensaat line and the line from point O to the foot-print center （∠2）, the distance from point O to the posterolateral bundle center and the angle between the Blumensaat line and the line from point O to the foot-print center （ ∠3） were measured. The above method was used in the clinical ACL reconstruction of 10 cases of simple ACL injury to pinpoint the femoral foot-print of ACL. Results In the 37 knees suitable for single-bundle reconstruction, the distance from point O to the foot-print center was 1.24 cm and ∠ 1 43.4° on average. In the 32 knees suitable for double-bundle reconstruction, the distance from point O to the anteromedial foot-print center was 0. 90 cm and ∠2 44. 5° on average, and the distance from point O to the posterolateral foot-print center was 1.48 cm and ∠3 47.9° on average. Dual-source CT scan showed fine accuracy and repeatability of the measurements by this novel method used in the 10 cases of clinical ACL reconstruction. Conclusions Since this novel method can well pinpoint the femoral foot-print of ACL, single- or double-bundle reconstruction can be determined in the preoperative planning for ACL reconstruction. It also benefits the local- ization of femoral bone tunnel and individualized anatomic reconstruction of ACL injury.