Question: When injured, the iliolumbar ligament causes pain down the back of the leg to the foot. True or false?

Answer: False. The iliolumbar ligament does not refer pain below the thigh.

The iliolumbar ligament is an often-ignored but important ligament. When you put your hand on your hip, your thumb probably is on this structure. The iliolumbar ligament attaches the fifth transverse process to the anterio-medial superior lip of the crest of the ilium. It stabilizes the connection between the low back and pelvis, and limits side-flexion of the trunk.

When an iliolumbar ligament is injured, bending to the side usually causes pain. It might be painful to bend to the side where the injury is located or to bend to the opposite side. For instance, if bending to the right causes pain on the left, this indicates the ligament on the left is injured and is being stretched. If bending to the right causes pain on the right, this indicates the ligament on the right is injured and is being compressed. An injured iliolumbar ligament might refer pain to the lateral hip, the groin and genital areas, the medial thigh and across the low back just above the ilium on the injured side.

Injuries to the iliolumbar ligament attachment at the transverse process are rare. This is fortunate because such injuries are very difficult to reach manually. Injury generally occurs at the attachment to the ilium, which is accessible to the therapist's fingers. Treatment typically involves friction therapy of the ligament twice a week, followed by massage therapy of the low back and hip. Special exercises also are given to put the ligament under some tension to strengthen it.