What Is Cuboid Syndrome?

Cuboid Syndrome: A Source Of Lateral Foot Pain

Cuboid syndrome is a relatively common source of pain experienced on the outer side of the midfoot. The syndrome is considered to involve subluxation of the cuboid bone, one of the small bones of the midfoot. The cuboid is positioned on the outer side of the foot, little toe side of the foot and the cuboid specifically articulates with among others the heel bone (known as the calcaneus). Connective tissue comprising of a number of strong ligaments and joint capsule help the calcaneus and cuboid bone form the calcaneocuboid joint. Subluxation (a partial dislocation) of the calcaneocuboid joint as is suggested to occur in cuboid syndrome may occur suddenly due to trauma such as associated with suffering a lateral ankle sprain, or develop more gradually overtime from repetitive loading through the foot. Forces either gradual and repetitive, or sudden and violent may stress/damage supporting soft tissues of this joint, causing the cuboid bone to “move out of position”. Once the cuboid has moved out of position as a result of such stress and is “subluxed” it may act like a block in the foot, limiting the movement of surrounding bones. Hence other names that cuboid syndrome is referred to as in the medical world include; blocked cuboid, dropped cuboid, or cuboid subluxation.

During weight bearing activities such as running or jumping, as load is placed on the foot, stress is exerted on the cuboid bone and associated supportive connective tissues. It is considered that contraction of the peroneus longus muscle and certain movements of the foot and ankle beyond what the body can withstand may lead to strain and potentially tearing of the supportive connective tissue. This excessive load and connective tissue stress may cause the cuboid to shift from its normal alignment, or sublux, leading to cuboid syndrome.

Causes Of Cuboid Syndrome

There are a few common causes considered to contribute to someone developing cuboid syndrome, a few of these are listed briefly below:

• Repetitive Stress: Repetitive contraction of the peroneus longus muscle which is a plantarflexor of the foot as well as everts the sole of the foot, may create cuboid syndrome through the excessive traction this muscle can place on the cuboid. The peroneus longus muscle runs down the outside of the lower leg passing behind the lateral ankle bone crossing the outside of the cuboid, and then runs on the under surface of the cuboid in a groove finishing up under the base of the foot towards the big toe side.

Jumping and running engage the peroneus longus muscles role in plantarflexion and inversion-eversion control, hence athletes like ballet dancers and runners are considered somewhat prone to developing cuboid syndrome. In this non-traumatic overload situation the symptoms of cuboid syndrome come on gradually over time, rather than immediately as the result of a trauma such as following an inversion ankle sprain.

• Injury: A common cause of cuboid syndrome is from spraining your ankle, specifically an inversion ankle sprain. An inversion sprain is an injury where the foot and heel are turned inwards excessively and are common when landing on someones foot following jumping in sports like basketball, or netball, in tackles playing soccer, or other football codes, as well as in every day life such tripping wearing high heels, o, missing a step or curb simply walking. Trauma and accidents like these can result in the cuboid bone being “forced outwards” and can damage the connective tissues supporting the cuboid. This may potentially cause cuboid subluxation, or impared ability for the body to maintain the cuboid in its correct position under load following a sprain.

• Altered Foot Biomechanics: Variations in foot posture such as having overly pronated feet (flat feet), or lateral ankle instability (an unstable ankle as a result of previous ankle sprains, or severe hypermobility) can also increase someone’s likelihood of experiencing cuboid syndrome.

Disclaimer: Sydney Physio Clinic provides this information as an educational service and is not intended to serve as medical advice. Anyone seeking specific advice or assistance on What Is Cuboid Syndrome? should consult his or her general practitioner, physiotherapist, sports medicine specialist, orthopedic surgeon or otherwise appropriately skilled practitioner.