Midfoot Trauma

Radiographic findings may include:

  • a linear or curvilinear decreased density dividing a bone into two or more segments
  • less than 100% apposition between two bones at a joint

Differential Diagnosis:

  • os intermetatarseum
  • os infranaviculare
  • os supratalare
  • os peroneum
  • sesamoid in anterior tibialis tendon
  • accessory navicular
  • bipartite navicular
  • bipartite medial cuneiform

Here are presentations of midfoot trauma and related variants (with *interpretations):

  • Case 1
  • *Case 1
  • Case 2
  • *Case 2
  • Case 3
  • *Case 3
  • Case 4
  • *Case 4
  • Case 5a
  • *Case 5a
  • *Case 5b
  • *Case 5c
  • Case 6a
  • Case 6b
  • *Case 6a
  • *Case 6b
  • *Case 6c
  • Case 7a
  • Case 7b
  • *Case 7a
  • *Case 7b
  • Case 8
  • *Case 8
  • Case 9
  • *Case 9
  • Case 10
  • *Case 10
avulsion fracture navicular
avulsion fracture navicular marked

Lateral view. A triangular-shaped segment of bone is separated from the superoposterior corner of the navicular (arrow). It is angulated and slightly displaced superiorly and posteriorly. The discontinuity extends into the talonavicular joint space. Diagnosis: intra-articular avulsion fracture, navicular.

navicular avulsion fracture
avulsion fracture navicular lateral marked

Lateral view. Findings include an ill-defined, linear decreased density that separates a small flake of bone along the superior surface of the navicular. Diagnosis: avulsion fracture.

os supranaviculare
os supranavicular marked

A well-defined ossicle presents along the superoposterior corner of the navicular at the talonavicular joint. Diagnosis: os supranaviculare.

os infranaviculare
os infranaviculare marked

Lateral view. Three well-defined ossicles are seen: the one superior to the intermediate cuneiform-navicular joint demonstrates irregular cortical margins and articjhlates with the navicular (NU); a circular shaped ossicle appears to float above the talonavicular joint (OS); a large well-defined ossicle articulates with the talar posterolateral process posteriorly (OT). Diagnoses: nonunion avulsion fracture of the anterosuperior corner of the navicular versus os infranaviculare; os supratalare versus losse body; os trigonum.

accessory navicular fracture
accessory navicular fracture marked

DP view. The ossicle sitting just posterior to the navicular tuberosity, when compared to a previous film (*Case 5b), is fragmented and exhibits bone resorption. Diagnosis: fractured accessory navicular type II.

accesory navicular before fracture

DP view of the same patient in Case 5a but two years earlier. Normal accessory navicular type II (AN).

Accessory navicular 1accessory navicular 2accessory navicular 3

accessory navicular 1 marked accessory navicular type 2 markedaccessory navicular navicular type 3 marked

Accessory navicular types I, II, and III. Type I (arrow) is a sesamoid in the tibialis posterior tendon (aka the os tibiale externum); type II is an accessory ossification center for the navicular tuberosity that articulates with the body (AN2); type III is an accessory ossification center for the navicular tuberosity that is united, i.e., a synostosis (AN3) and has the appearance of an elongated tuberosity.

bipartite medial cuneiform DP
bipartite medial cuneiform lateral
bipartite medial cuneiform DP

Dorsoplantar view. Nothing obvious is visible. However, you may be able to trace the outline of a smaller medial cuneiform bone superimposed within a larger one. Diagnosis: bipartite medial cuneiform.

bipartite medial cuneiform lateral

Lateral view. Medial cuneiform is divided into equal top and bottom sections. Diagnosis: bipartite medial cuneiform.

subungual exostosis

CT bone window, sagittal plane image. Medial cuneiform is divided (arrows) into equal top and bottom sections. Diagnosis: bipartite medial cuneiform.

bipartite navicular DP view
bipartite navicular lateral view
bipartite navicular DP view marked

Dorsoplantar view. Notice how narrow the navicular is laterally; this is a common finding with this rare variant. The two segments cannot be appreciated in this view. Diagnosis: bipartite navicular.

bipartite navicular lateral view marked

Lateral view. The navicular is obliquely divided (arrow) into top and bottom sections. SL = smaller superolateral segment. Diagnosis: bipartite navicular.

navicular fracture body
navicular fracture body marked

Dorsoplantar view. A linear decreased density (arrows) runs anteroposteriorly through the navicular dividing it into two unequal-sized segments. It extends into both the naviculocuneiform and talonavicular joints. Diagnosis: intra-articular navicular fracture.

navicular tuberosity avulsion fracture
navicular tuberosity avulsion fracture marked

Lateral oblique view. An ill-defined curvilinear decreased density separated the navicular tuberosity from the body. Diagnosis: navicular tuberosity avulsion fracture.

LisFranc fracture/dislocation
LisFranc fracture/dislocation marked

Dorsoplantar view. The first through fiftth metarsal bases do not articulate with their respective tarsal bones. Diagnosis: LisFranc dislocation. (CT would be necessary to visualize any fracture fragments in this case.) mc = medial cuneiform; im = intermediate cuneiform; lc = lateral cuneiform; 2 = 2nd metatarsal base; 3 = 3rd metatarsal base; c = cuboid.

Should a radiographic study be ordered for suspicion of midfoot/rearfoot fracture?

Definitely yes.

What are the best views to order?

At a minimum order DP and lateral views. Oblique views are not necessary but can be valuable when evaluating the following anatomic area:

  • cuboid: medial oblique
  • navicular tuberosity: lateral oblique
  • metatarsal-tarsal joints: medial oblique

CT may be necessary for pathology that is inconclusive on plain films.

Other information

Cuboid fractures are very uncommon.

Bipartite medial cuneiform may be associated with medial arch pain.

References:

  1. Christman RA: Foot and Ankle Radiology, 2nd edition, Lippincott Williams & Wilkins, 2015.