Defining a Common Peroneal Nerve Safety Corridor for Minimally Invasive Posterolateral Corner Reconstruction
J.G.D.C.C. Villardi, R.E. De Paula, C.P. Helito, N.S.L. Ramos, M.D.M. Ramos, A.M. VillardiObjectives:
To quantify the distance from a standardized center point on the fibular head to the anterior border of the common peroneal nerve (CPN) at 0°, 45°, and 90° of knee flexion, and to define a practical safety corridor.
Methods:
Eighteen formalin-preserved cadaveric knees were dissected. After exposing the CPN and fibular head, a vertical line from the fibular head apex to the neck and a horizontal line at maximal head width defined a center point. Using a digital caliper (0.01-mm resolution), we measured the shortest distance from that point to the anterior CPN border at 0°, 45°, and 90°. Repeated-measures statistics compared angles; effect sizes and 95% CIs were calculated.
Results:
Mean (±SD) fibular head width and height were 20.84 ± 1.96 mm and 31.33 ± 1.23 mm, respectively. Mean CPN distances increased with flexion: 11.05 mm (0°), 12.19 mm (45°), 13.38 mm (90°). Repeated-measures analysis showed significant angle effects with pairwise differences between all angles i.e. between 0° x 45° (
Conclusion:
The CPN moves farther from the fibular head center with increasing flexion, maximizing the safety corridor at 90°. These data support minimally invasive posterolateral corner techniques targeting the fibular head center point, preferably at 90° of knee flexion, while recognizing anatomical variability.