Do you have pain and weakness along the outside of your foot? Perhaps you have a history of a traumatic sprain from landing on another person’s foot or falling off a curb. Maybe there is no history of acute trauma but gradual onset of pain over a period of time that doesn’t respond to physical therapy, injections or anti-inflammatories? Sounds like cuboid subluxation syndrome!
What Causes Cuboid Subluxation Syndrome?
Injury to the joints and ligaments around the cuboid bone during an inversion ankle sprain results in cuboid subluxation syndrome. Cuboid syndrome is a common cause of lateral foot pain in the athletic population and is often misdiagnosed or mistreated. It is a minor disruption or subluxation of the structural integrity of the calcaneocuboid portion of the midtarsal joint.
An athlete with a cuboid subluxation will complain of lateral foot pain and weakness in push-off. The pain often radiates to the plantar aspect of the medial foot, the anterior ankle joint or distally along the fourth ray. It is common in ballet dancers and runners.
During a physical exam, there is pain upon palpation on the plantar surface of the cuboid. Sometimes the subluxation can be reproduced, but not often since it is usually subtle. It is important to be aware that diagnosing cuboid syndrome via radiographs, computerized axial tomography (CT) scans or magnetic resonance imaging (MRI) is difficult because of the normal variations that exist between the cuboid and its surrounding structures, and the minimal amount of subluxation that is usually present.
What else could it be?
- Sinus tarsi syndrome
- Lateral process fracture of the talus
- Acute tendinitis of the peroneus longus tendon
- Fracture of the anterior process of the calcaneus
- Malalignment of the lateral ankle and subtalar joints
- Fractures (including stress fractures)
- Gout Inflammatory and noninflammatory arthritis
- Tarsal coalitions (in adolescents)
Once one has diagnosed cuboid syndrome, reducing the subluxed cuboid is the first step in the treatment process. Clinicians may employ a manipulative technique, which is often defined as a low-amplitude, high-velocity mobilization at the end of joint range, to restore proper joint congruency.
Afterward, patients should use a cuboid pad in conjunction with a taping technique to maintain the cuboid reduction and give the arch added support. Keep in mind that the cuboid pad may at times spontaneously adjust a mildly subluxed cuboid by its upward thrust. Long-term treatment is a semirigid orthotic with a cuboid pad placed on the device. Physical therapy techniques are often used to return normal foot function. Patients may gradually return to sports activity when the pain subsides.
Keep in mind that cuboid subluxation following a second-degree or third-degree lateral foot sprain requires special care in order to prevent the development of a chronic condition. If one suspects a cuboid subluxation after a lateral foot sprain, reduction is not attempted until the swelling and bruising have significantly diminished and the possibility of a fracture has been ruled out.
Bottom line: after an inversion sprain, if you still have lateral foot pain once the swelling has gone down, you may have subluxing cuboid syndrome. An evaluation and treatment of a subluxed cuboid is essential in order to restore normal joint range of motion, alleviate pain and improve foot function.