The interosseous membrane is a thick dense fibrous sheet of connective tissue that spans the space between two bones forming a type of syndesmosis joint.
In the upper limb, the interosseous membrane is between the radius and ulna. It divides the forearm into anterior and posterior compartments and also serves as an attachment for several deep muscles of the forearm and hand.
In the lower limb, the interosseous membrane is between the tibia and fibula. Along with the anterior and posterior intermuscular septae, it divides the leg into several compartments and also serves as an attachment for several deep muscles of the leg and foot.
In both the forearm and leg, the interosseous membrane may be pierced by vessels.