Which ligament anchors the spinal cord laterally to the dural sac?

The denticulate ligaments are responsible for anchoring the spinal cord laterally to the dural sac. These ligamentous structures are extensions of the pia mater that form tooth-like projections and attach to the inner aspects of the dura mater at regular intervals along the length of the spinal cord. This anchoring provides lateral stability to the spinal cord within the vertebral column, helping to prevent excessive movement or rotation that could potentially damage the spinal cord or disrupt its function.

In contrast to the denticulate ligaments, the filum terminale is a fibrous extension of the pia mater that anchors the spinal cord at its lower end to the coccyx but does not provide lateral stabilization. The anterior spinal artery is a blood vessel that supplies blood to the anterior portion of the spinal cord and does not have a supportive role. The cauda equina, comprised of spinal nerves that extend beyond the termination of the spinal cord, does not provide anchoring to the spinal cord itself, as it primarily consists of nerve roots. Hence, the denticulate ligaments are specifically designed to provide the necessary lateral attachment to the dural sac.