Ultrasound Evaluation of Peroneal Tendon Location Within the Fibular Groove

Abstract

Category: Sports Introduction/Purpose: The use of MRI in diagnosing peroneal tendon dysfunction can be difficult due to the anatomic orientation of the tendons and their relationship to the posterior fibula. MRI is also limited in its roll in diagnosing dislocation or intrasubstance subluxation due to the static nature of the examination. Due to these limitations Ultrasound has become increasingly more common. The purpose of this study was to identify the location of the peroneal tendons in relationship to the fibular groove during a dynamic examination in an asymptomatic population of elite United States Military Service members. Methods: We conducted a prospective cohort study composed of 41 active duty United States Army Rangers. Each subject was examined bilaterally. Subjects were placed in a lateral recombinant position and the ankle placed in a resting neutral position to visualize the tendon in a retromalleolar short-axis view. Next, maximum active ankle eversion followed by gravity inversion while the ultrasound probe was maintained in its original position. The distance from the fibrous lateral ridge of the retromalleolar groove to the anterior aspect of the peroneal brevis was measured in the short-axis in all three positions (Neutral, Eversion and Inversion). Results: The mean sagittal distance was 0.48 mm. No subjects demonstrated greater than 1 mm difference between the three positions, no dislocations were identified. The side to side difference and dominant vs non-dominant differences were not statically significant. Conclusion: The current study demonstrates the distance between the peroneal brevis and the lateral fibular ridge is consistent throughout extremes of motion in an asymptomatic population. These results help further the understanding of the peroneal tendons while performing a dynamic exam. Our findings also establish side-to-side consistency prompting a bilateral examination to help identify abnormal pathology. The current study also offers clinicians another means of evaluating reported peroneal tendon subluxation prior to MRI or further subspecialty consultation.