ILIOLUMBAR LIGAMENT INSERTIONS - IN-VIVO ANATOMIC STUDY

Study Design. Using magnetic resonance imaging, this study analyzed th e anatomic characteristics of the iliolumbar ligament insertion on hum ans. Objectives. To resolve certain anatomic questions about the manne r of insertion of the iliolumbar ligament. Summary of Background Data. The data of the postmortem studies of the iliolumbar ligament are con troversial because of the number, complexity, and variability of the s tructures present in the lumbosacral region. Methods. Twenty-eight ili olumbar ligaments of 14 adult volunteers were analyzed with magnetic r esonance imaging. The images were acquired along the transversal plane s (from inferior to superior) and coronal planes (from the ventral to the dorsal) of the lumbosacral region. Results. The anterior band of t he iliolumbar ligament (broad and flat) originates from the anterior-i nferior-lateral part of the L5 transverse process and expands as a wid e fan before inserting on the anterior part of the iliac tuberosity be low the posterior band. The posterior band of the iliolumbar ligament originates from the apex of the L5 transverse process and is thinner t han the anterior with a round section, and it inserts on the iliac cre st (from the anterior margin to the apex). Conclusions. The minor widt h of the area of insertion on the iliac crest of the posterior band (a nd therefore its lower resistance with the mechanical overloads) could explain the frequency of the painful syndromes related, by some autho rs, to an enthesopathy of this ligament.