Midfoot width changes after first metatarsal osteotomy in hallux valgus surgery: A biomechanical effect?

Hallux valgus is a challenging pathology characterized by a valgus deformity in the metatarsophalangeal area of the first ray. The aim of this study was to analyze the influence of first metatarsal osteotomy on the relationship between midfoot bones in patients with hallux valgus. The sample consisted of patients from the orthopedics and traumatology outpatient clinic who underwent surgical treatment for hallux valgus. Preoperative and postoperative X-rays were compared regarding the width of the midfoot and the tarsometatarsal joint. The sample consisted of 17 women, with 22 feet assessed in each group. The distance from the medial cuneiform to the cuboid, the distance from the intermediate cuneiform to the cuboid, the distance between the first and fifth metatarsals, and the distance between the second and fifth metatarsals reduced significantly between pre- and postoperative assessments. Hallux valgus correction through osteotomy of the first metatarsal leads to a structural change in the midfoot. Further studies should determine whether these changes persist over time.

Open-source navigation system for tracking dissociated parts with multi-registration

PURPOSE

During reconstructive surgery, knee and hip replacements, and orthognathic surgery, small misalignments in the pose of prosthesis and bones can lead to severe complications. Hence, the translational and angular accuracies are critical. However, traditional image-based surgical navigation lacks orientation data between structures, and imageless systems are unsuitable for cases of deformed anatomy. We introduce an open-source navigation system using a multiple registration approach that can track instruments, implants, and bones to precisely guide the surgeon in emulating a preoperative plan.

METHODS

We derived the analytical error of our method and designed a set of phantom experiments to measure its precision and accuracy. Additionally, we trained two classification models to predict the system reliability from fiducial points and surface matching registration data. Finally, to demonstrate the procedure feasibility, we conducted a complete workflow for a real clinical case of a patient with fibrous dysplasia and anatomical misalignment of the right femur using plastic bones.

RESULTS

The system is able to track the dissociated fragments of the clinical case and average alignment errors in the anatomical phantoms of [Formula: see text]  mm and [Formula: see text]. While the fiducial-points registration showed satisfactory results given enough points and covered volume, we acknowledge that the surface refinement step is mandatory when attempting surface matching registrations.

CONCLUSION

We believe that our device could bring significant advantages for the personalized treatment of complex surgical cases and that its multi-registration attribute is convenient for intraoperative registration loosening cases.

Radiographic angular measurements of the foot and ankle in weight-bearing: A literature review

BACKGROUND

For the diagnosis and treatment of the foot and ankle, bone alignments have long been evaluated using planar radiographs in weight-bearing conditions and a large number of measurements have been reported. The present survey reviews the major radiographic angles that are currently present in the literature for a possible better comprehension and classification of them.

METHODS

PubMed and Google Scholar were used to retrieve technical and clinical papers related to these angles, and were classified based on five typologies and the three projection planes. These angles were grouped into one definition if they described similar concepts, regardless of their anatomical references and names. A corresponding original definition and diagrammatic representation are offered.

RESULTS

Thirty-one conceptual radiographic angles were identified across all descriptions from the literature: 18 in the sagittal plane, 9 in the transverse, and 4 in the coronal. Most angular measures represent relative bone orientations; absolute orientations, bone morphology and joint lines are less frequently used or reported.

CONCLUSIONS

The present survey reveals a confused scenario of angular measures, particularly in terms of anatomical references and names. It is therefore recommended to establish common relevant techniques and terminology.