Cuboid syndrome is treated by reducing (realigning) the subluxation of the calcaneo cuboid joint and stabilizing the reduction. Reduction of the subluxation can be accomplished by manipulating the joint. Manipulation is performed with the patient in a prone (face down) position.
Best person is podiatric orthopedician.
Cuboid syndrome is a common cause of lateral foot pain in the athletic population and is often misdiagnosed or mistreated. It is usually defined as a minor disruption or subluxation of the structural integrity of the calcaneocuboid portion of the midtarsal joint. There are many synonyms for this condition including: lateral plantar neuritis, cuboid fault syndrome, dropped cuboid, locked cuboid and subluxed cuboid.
You should take him for a podiatric orthopedic specialist for proper therapy and follow up.