The cuboid bone is one of many bones in the foot. It is situated close to the center of the foot and is surrounded by other bones. It is an oddly shaped bone with smooth places (the articular surfaces) where the other bones connect. The bones connected to the cuboid are held together by ligaments, tendons, and a thick fibrous attachment called the labrum.
The first thing to know about cuboid syndrome is that it feels a lot like an ankle sprain with tenderness and pain along the lateral (outside) edge of the foot. Loss of ankle/foot motion and pain on standing or other weight-bearing activities are other common symptoms. Other names for this condition are cuboid fault syndrome, dropped cuboid, subluxed cuboid, locked cuboid, peroneal cuboid syndrome, and lateral plantar neuritis.
The main area where the cuboid bone makes contact with the calcaneus (heel bone) is called the calcaneocuboid (CC) joint. This is an important joint for stability, load transfer, and movement of the foot and ankle. As some of the names for this condition suggest, a shift in the position of the cuboid bone can cause loss of motion with the bone “locked” in place. The surfaces of the connecting bones no longer line up. This effect with the accompanying symptoms is a cuboid syndrome. When this happens, we say the joint has lost its congruence.
The loss of congruence can be small enough that it doesn’t show up on an X-ray or other types of imaging studies. Lateral foot pain could be caused by a number of other problems. The list of possible sources of lateral foot pain includes gout, compression neuropathy of the sural nerve, ankle impingement, tendinopathy, or congenital fusion of the bones in that area (calcaneus, navicular, talus).
Cuboid syndrome is clearly a mechanical problem but one that could be caused by impaired muscle or tendon function, faulty anatomy such as flat feet, being overweight, or wearing the wrong kind of shoes. Other factors that may increase the risk of developing cuboid syndrome include poorly constructed orthotics (shoe inserts), training on hard or uneven surfaces, and overtraining without enough rest or time to recover.
As these risk factors suggest, athletes and especially ballet dancers are affected most often by cuboid syndrome. In fact studies show that four per cent of all athletes with foot pain have pain coming from the cuboid gone. And in several studies, 17 per cent of ballet dancers examined with lateral foot pain had cuboid syndrome. Anyone (athlete or nonathlete) who has sprained an ankle is also at risk for this problem.
If the treatment for cuboid syndrome is applied and the symptoms go away, the diagnosis may be confirmed.
Treatment is with manipulation of the bones. The examiner holds the foot to stabilize the bones around the cuboid and then applies a force to shift the bone back in place. The patient may feel and/or hear a click or pop. Immediate pain relief is often reported after manipulation.
It may take more than one manipulation to completely resolve the problem. The longer you have had this condition, the more likely that a series of manipulations will be needed. Manipulation may be followed by local treatment such as icing, taping, ultrasound (heat), massage, or electrical stimulation. Stretching of the leg muscles and/or shoe inserts to support the cuboid bone may be provided.
In cases of acute (recent) ankle/foot sprain, a high-velocity thrust manipulation may not be appropriate. It may be better to apply this treatment method after the injured soft tissues have had time to heal and can withstand the force of a manipulative movement.
Anyone with lateral foot pain who does not respond to treatment for a cuboid syndrome may have some other problem. At that point, reevaluation is required. It may be that there is a sprain severe enough to require unloading with a cane or crutches or off-loading in a cast or splint. If an X-ray has not been previously taken, this may be the time to take one.