Navicular Stress Fracture

Crystal is an elite basketball player who landed on her right foot after doing a jump shoot and suffered from severe foot pain a week ago. She was taken off the court as she could not continue weight-bearing. Subsequently, she was seen by another colleague and found to be having tenderness and fullness (oedema) over the inner portion of the dorsum of her right foot. Her X-rays showed a Type III Navicular Fracture.

Anatomy:

The navicular bone, located in the midfoot, articulates with the head of the talus, cuboid, and the three cuneiform bones that are involved in the acetabulum pedis. It gives attachment to the spring ligament (superomedial and inferior calcaneonavicular ligament)that can be injured in a failure of the posterior tibialis tendon and cause an adult acquired flatfoot deformity. The navicular bone provides insertion for the posterior tibialis tendon. Some pathologies can be related to the presence of an accessory navicular bone.Osteonecrosis or stress fractures can affect the navicular bone because of its poor vascularization, especially in its central portion.

Radiological classification of Navicular Fracture: dorsal cortical break (type I), fracture propagation into the navicular body (type II), and fracture propagation into another cortex (type III). It includes modifiers "A" (avascular necrosis of a portion of the navicular); "C" (cystic changes of the fracture), and "S" (sclerosis of the margins of the fracture).


She was placed in a non-weight bearing cast for 4 weeks (as she wanted play if there was no pain!). I saw her at 4 weeks post-injury and her repeat X-ray did not show much callous formation. She was placed in a functional walking brace (Donjoy) and advised minimal weight bearing for another 2-4 weeks. She was told that such fractures may take a longer period to heal and some studies suggest that surgery (ORIF) may be an option. I prescribed her low frequency ultrasound treatment (Exogen) to encourage bone healing. Most studies suggest that conservative (non-surgical) management provide good results for non-displaced navicular fracture but a few small studies suggest that elite athletes may benefit from surgery in type II or III fractures. Return to sporting activity varies from 3.0 months (Type I), 3.6 months (Type II) and 6.8 months (Type III) according to Saxena et al*.

*J Foot Ankle Surg. 2000;39(2):96-103