Length Changes of the Medial Patellofemoral Ligament During In Vivo Knee Motion: An Evaluation Using Dynamic Computed Tomography

Study Overview
This study focused on understanding the elongation patterns of the medial patellofemoral ligament (MPFL), the primary passive stabilizer against lateral patellar dislocation. To better understand the in vivo elongation behavior of the MPFL, this study analyzed virtual length changes of MPFL fibers during active flexion–extension movements in 115 healthy knees from 63 participants using dynamic CT scans. All participants provided written informed consent for secondary use of their data.

Methods Summary
Static and dynamic CT scans captured non–weight-bearing flexion–extension–flexion movements of both knees. For each knee, virtual MPFL fibers were modeled from Schöttle’s point on the femur to three patellar insertion sites along the superomedial border: proximal, central, and distal. The central insertion was located at the proximal one-third of the patellar height, while the proximal and distal insertions were positioned 15% above and 15% below the central insertion, respectively. Fiber length changes were evaluated per degree of flexion during the extension phase.

Collection description
- Pseudonymized participant characteristics
- Per knee virtual MPFL fiber length change per degree of flexion for the proximal, central and distal patellar insertion. Both absolute and percentual length changes relative to the fiber length in extension (0 degrees of flexion) are shared.
- Percentile data on the virtual MPFL fiber length change per degree of flexion for the proximal, central and distal patellar insertion. Both absolute and percentual length changes relative to the length in extension (0 degrees of flexion) are shared.

Intended use
These data are provided for readers who wish to examine the quantitative results underlying Figure 4 in the article in more detail.