RESUMEN
The hip capsule has been recognized as a vital structure in the stability and proper function of the hip. Preserving its integrity during arthroscopic surgery is one of the utmost important principles in hip preservation surgery. When capsular deficiency is present, capsular reconstruction may be indicated to restore stability and proper hip mechanics. In this technical note, we introduce a simple and reproducible shuttle method technique for hip capsular reconstruction using a dermal allograft.
RESUMEN
Tibial anterolateral rotary instability associated with anterior cruciate ligament (ACL) tears is a well-documented and difficult problem with a long history of solutions. The lateral extra-articular tenodesis (LET) has undergone multiple refinements in technique, largely focusing on the femoral site insertion using either an interference screw versus a staple for adequate fixation. In this article, we present an improved technique using a suture anchor as an alternative to a staple or an interference screw with secure fixation to insert the LET graft onto the femur. This technique diminishes the chance of ACL tunnel-LET drilling convergence, minimizes the footprint required for adequate graft fixation, and allows the surgeon to dial in the correct tension necessary for adequate augmentation of an ACL reconstruction.
RESUMEN
Introduction Femoral torsion is an important anatomical consideration of the hip that has major implications on the natural motion of the hip joint. Similarly, it affects pathologic conditions of the hip, including femoroacetabular impingement, dysplasia, and/or microinstability. Femoral torsion is typically measured on two-dimensional (2D) axial CT cuts by creating the angle between the femoral neck and the posterior aspect of the ipsilateral femoral condyles. Position of the leg during imaging may affect 2D measurements. Three-dimensional (3D) analysis of a hip CT with inclusion of femoral alignment may portray the anatomy of the hip more accurately as compared to a 2D slice-based analysis of a hip CT scan. It is thought that femoral torsion measured using this system could be a more accurate and reliable means of measurement. The primary purpose of this study is to assess the differences in measuring femoral torsion with 3D modeling and analysis compared to the standard 2D slice-based approach on a CT scan. Secondarily, we attempt to determine how the passive range of motion of the hip correlates with femoral torsion measured using the 3D model versus the 2D model. Methods In a prospective cohort study of 20 patients, femoral torsion was assessed using both 2D analysis and 3D analysis. The differences between these measurements on each of the imaging modalities were compared. Additionally, each patient had the passive range of motion of their hip measured with a goniometer. The amount of internal and external rotation was measured with the hip in a neutral position and with the hip flexed to 90°. Acetabular version, combined version, and alpha angle were added to multivariate regression analysis to evaluate their effect versus femoral torsion alone. Results Femoral antetorsion measured using the standard 2D slice-based approach on CT scan was 22.1° (SD: 11.1°), which was higher (p<0.001) than that using 3D analysis (8.25°; SD: 10.5°). There was a strong correlation between femoral torsion measurements using 3D analysis and 2D analysis (R=0.91). Based on 3D analysis, there was a moderate correlation between femoral torsion and passive hip external rotation measured with the hip flexed to 90° (R=0.65, p<0.002) and with the hip in a neutral position (R=0.58, p<0.007). Conclusion There was a significant difference between femoral torsion measurements using the 3D analysis, which showed approximately 14° of less antetorsion on average. Additionally, rotation of the hip and femoral torsion was correlated to higher levels of antetorsion associated with more internal rotation of the hip.
