An additional middle cuneiform?

Bipartite medial cuneiform: magnetic resonance imaging findings and prevalence of this rare anatomical variant

OBJECTIVE

To describe the imaging features of bipartite medial cuneiform and to determine the prevalence of this rare anatomical variant in a large group of patients that were evaluated by magnetic resonance imaging (MRI) of the foot.

MATERIALS AND METHOD

Seven hundred and fifty-one patients that underwent MRI of the foot from May 2016 to December 2018 were included in the study (mean age 49 years; 540 females; 211 males). All MRIs were retrospectively analyzed to identify bipartite medial cuneiform. For patients with bipartite medial cuneiform, we analyzed partial and complete bipartition, the type of articulation (synchondrosis, syndesmosis, or a combination of these two), and stress changes related to abnormal motion (i.e., subchondral cysts and sclerosis). Bone marrow edema-like signal, diastasis in the cleavage plane, concomitant fractures, and the presence of the E-sign were also evaluated.

RESULTS

Nine feet from six patients presented bipartite medial cuneiform on the MRI. Six and three feet exhibited complete and partial bipartition. All patients were referred for MRI because of midfoot pain, of which two had history of trauma prior to imaging. Stress changes related to abnormal motion were observed in three feet (34%), all with complete bipartition. Bone marrow edema-like signal was recorded in five feet (55%) and diastasis in one foot (11%). No fractures were present in the bipartite medial cuneiform. All patients had E-signs.

CONCLUSION

Bipartite medial cuneiform is a rare anatomical variant occurring in 0.79% of patients who underwent foot MRI in this study. It is important to be aware of this variant as it is a cause of midfoot pain. Being familiar with the E-sign helps identify and differentiate it from a fracture.

Anatomical variation in the ankle and foot: from incidental finding to inductor of pathology. Part II: midfooot and forefoot

Accessory anatomical structures in the ankle and foot usually represent incidental imaging findings; however, they may also eventually represent a source of pathology, such as painful syndromes, degenerative changes, be the subject of overuse and trauma, or appear as masses and cause compression syndromes or impingement. This review aims to describe and illustrate the imaging findings related to the presence of accessory ossicles and muscles in the midfoot and forefoot through different techniques, with special attention on those variants that associate factors of clinical relevance or that would trigger challenges in the differential diagnosis.

Symptomatic Os Intercuneiform: A Case Report

We encountered a case of an accessory bone in the foot in the distal portion of the tarsal navicular and the proximal portion of the intermediate cuneiform, namely an os intercuneiform. The patient presented with a history of pain on the dorsal aspect of the left foot, with tenderness and swelling. Perioperative findings revealed a synfibrotic connection between the accessory bone and the navicular and intermediate cuneiform. After unsuccessful conservative treatment, the accessory bone was excised, leading to postoperative symptomatic relief.