Dropped Cuboid
The cuboid is the keystone of the lateral column of the foot and is the only bone linking the lateral column of the foot to the transverse arch of the foot.
Cuboid syndrome is a relatively common cause of lateral foot and ankle pain. The syndrome itself is defined as a minor disruption or subluxation of the structural congruity of the calcaneocuboid portion of the midtarsal joint. The disruption of the cuboid’s position irritates the surrounding joint capsule, ligaments, and peroneus longus tendon (Blakeslee and Morris, 1987).
The more common presentation of cuboid dysfunction is the “Dropped Cuboid” where the patient describes lateral foot (dorsal and/or plantar) pain and a sense of stepping on a stone.
This injury can result from a compensated inversion sprain of the ankle. In this case the peroneal muscles contract strongly as the foot and ankle are inverting. As the calcaneocuboid joint is in a relative loose packed position in plantarflexion/inversion, the pull of the peroneus longus tendon, as it winds around the groove of the cuboid, pulls the cuboid into a plantar medial direction.
These injuries often respond well to manual therapy. The Hiss Whip technique is a common manipulation to reduce the cuboid subluxation. The arthrokinematic correction of a dropped cuboid is to mobilize it in a dorsal direction with conjunct external rotation. Chronic cases due to repetitive forces likely cause capsular and ligamentous stretching and may require orthotics to provide support under the medial and lateral columns as well as the transverse arch.
Reference:
Patterson, S.M. Cuboid Syndrome: A Review of the Literature. Journal of Sports Science and Medicine (2006) 5, 597-606.