Radiographic Analysis on the Distortion of the Anatomy of First Metatarsal Head in Dorsoplantar Projection

Abstract

Background: The diagnostic of flat and crest-shaped of first metatarsal heads has been associated as an important risk factor for hallux deformities, such as hallux valgus and hallux rigidus. The rounded form of the first metatarsal head on the dorsoplantar radiograph of the foot has been believed to be associated with the development of hallux valgus. Purpose: The aim of this study was to clarify the effect of tube angulation on the distortion of first metatarsal head shape, and verify the real shape of the metatarsal head in anatomical dissection after an X-ray has been taken. Materials and Methods: In this prospective study at Universidad Complutense de Madrid, from December 2016 to June 2019, 103 feet from embalmed cadavers were included. We performed dorsoplantar radiograph tube angulation from 0° until 30° every 5° on all specimens; then, two observers verified the shape of the first metatarsal head in the radiographs and after its anatomic dissection. Kappa statistics and McNemar Bowker tests were used to assess and test for intra and interobserver agreement of metatarsal shape. Results: We calculated the intraobserver agreement, and the results showed that the first metatarsal head is distorted and crested only when the angle of the X-ray beam is at 20° of inclination (p < 0.001). The interobserver agreement showed good agreement at 0°, 5°, 10°, 20°, and 25° and was excellent at 30° (p < 0.001). Conclusion: All of the studies that we identified in the literature state that there are three types of shapes of the first metatarsal head and relate each type of head to the diagnosis of a foot pathology, such as hallux valgus or hallux rigidus. This study demonstrates that there is only the round-shaped form, and not three types of metatarsal head shape. Therefore, no diagnoses related to the shape of the first metatarsal head can be made.

Adult Stature Estimation from Radiographic Metatarsal Length in a Contemporary Korean Population

“…Radiographic measurement of the bones of a living person offers the advantage of utilizing radiology in the display of skeletal structures without removing the surrounding soft tissue to avoid damage to the body. However, the method of indirectly measuring using radiographs may have limitations that may differ from the actual bone size because structures overlap in the radiographic image [ 39 , 40 ]. So, further study is needed to derive a formula for estimating the stature by measuring the actual metatarsal length in a cadaver with known antemortem stature.…”

Outcomes of Scarf and Akin Osteotomy with Intra-Articular Stepwise Lateral Soft Tissue Release for Correcting Hallux Valgus Deformity in Rheumatoid Arthritis

“…Exclusion from the application of joint-preserving procedure was judged by an experienced foot and ankle surgeon but did not follow such a strict guideline as using radiographic parameters in the present study. Although hallux valgus is a complex three-dimensional deformity, most of the commonly used parameters for evaluating hallux valgus, such as the hallux valgus angle, can only explain the deformity in the horizontal plane and might not evaluate the real three-dimensional deformity of the hallux [41,42]. Further studies with consideration of the three-dimensional deformity of the hallux will be needed to expand the application of joint-preserving arthroplasty in rheumatoid forefoot deformity.…”

Correlations of Sesamoid Bone Subluxation with the Radiologic Measures of Hallux Valgus and Its Clinical Implications

“…Flat foot and navicular bone drop are typical symptoms of hallux valgus. Patients may experience gradual changes in the alignment and shape of the forefoot and midfoot, and the changes frequently occur in the medial direction [ 6 ]. Medial deviation of the first metatarsal bone is common, along with lateral deviation of the first phalange, deformity of the phalangeal bone and interphalangeal joint, and pronation of the big toe in conjunction with sesamoid subluxation [ 7 ].…”