The unreliability of the intermetatarsal angle in choosing a hallux abducto valgus surgical procedure

Modified Lapidus Procedure and Hallux Valgus: A Systematic Review and Update on Triplanar Correction

This review article examines contemporary methods and assesses radiographic outcomes and postoperative complications following the modified Lapidus procedure. A systematic review demonstrated significant improvements in intermetatarsal angle, hallux valgus angle, and tibial sesamoid position. We are updating a modified Lapidus technique for achieving triplanar correction of hallux valgus. Two cases of hallux valgus, one primary and one recurrent, are presented. As demonstrated in the systematic review, outcomes of Lapidus procedures create future opportunities. Surprisingly, only 78% of the studies assessed for this review reported on the hallux valgus angle and only 33% reported on tibial sesamoid position.

Medium-Term Outcomes of Chevron Osteotomy for Hallux Valgus Correction in a Spanish Population: Radiologic and Clinical Parameters and Patient Satisfaction

BACKGROUND

Chevron osteotomy for mild and moderate hallux valgus obtains good effects. It is suitable for a variety of cases, allowing for a significant degree of correction. This study aimed to investigate chevron osteotomy for the correction of hallux valgus in the medium-term by podiatric surgeons. It considers clinical and radiologic findings and patient perspectives and level of satisfaction.

METHODS

Forty-five patients (50 feet) were assessed preoperatively, postoperatively, and at final follow-up. Mean patient age was 59.43 years (range, 32-80 years). The protocols include medical record review, clinical examination, and radiologic assessment. Anteroposterior weightbearing radiographs were analyzed preoperatively and at final follow-up. Clinical effects were analyzed with visual analog scale and American Orthopaedic Foot and Ankle Society (AOFAS) scores.

RESULTS

Interobserver and intraobserver reliability were evaluated. Mean ± SD hallux valgus angle decreased at final follow-up (25.30° ± 7.21° versus 17.25° ± 10.32°; P = .041). There was no significant reduction in mean ± SD intermetatarsal angle at final follow-up (13.13° ± 3.03° versus 7.65° ± 3.47°; P = .078). Final AOFAS score was 82.08 ± 17.66. This study showed the relevance of magnet therapy, nail surgery, and other procedures. No patient was dissatisfied with the aesthetic scarring.

CONCLUSIONS

The radiologic results at final follow-up were not compatible with relapse of the deformity. The definitive clinical results and the degree of patient satisfaction achieved with this technique were favorable from the patients' point of view.

Reliability of Visual Estimation of the First Intermetatarsal Angle

The size of the radiographic first intermetatarsal (IM) angle is one of the main considerations in selecting a surgical procedure for hallux abducto valgus. Instead of directly measuring the IM angle with a goniometer or a virtual measurement system, physicians will often estimate the size of the IM angle by direct visual estimation. The purpose of the present study was to determine the accuracy of visual estimation of the IM angle size compared with direct measurement. A total of 45 respondents, composed of students, residents, and attending physicians, reviewed a series of radiographs with IM angles varying from 6° to 19°. The attending physician visual estimates differed from the measured values by 3.28° ± 1.56°. The interrater reliability, as determined by the intraclass correlation (ICC), increased with experience by group category: 0.426 (95% confidence interval 0.239 to 0.672) for students, 0.476 (95% confidence interval 0.290 to 0.710) for residents, and 0.656 (95% confidence interval 0.483 to 0.833) for attending physicians. Larger IM angles, defined as >10° were less accurately estimated than were smaller IM angles (3.96° ± 1.60° [n = 24] for larger IM angles and 3.14° ± 0.79° [n = 21] for smaller IM angles; p = .0389). These results suggest caution when visually estimating IM angles, especially larger IM angles. Direct angle measurement might be more appropriate for surgical decision-making.

A passing glance? Differences in eye tracking and gaze patterns between trainees and experts reading plain film bunion radiographs

Eye tracking and gaze pattern studies have been used to evaluate human behavior for decades. This is because of its ability to reveal conscious and subconscious behaviors when subjects are tasked with observation, decision making, and surgical performance. Many have popularized the use of this technology for radiographic assessment while evaluating radiologist behaviors, but little has been described for surgeon behavior patterns when evaluating preoperative deformities by radiograph. Because the radiographic assessment strongly influences surgical selection, the present study was designed to evaluate the differences between groups of novice and experienced surgeons' gaze patterns when tasked to describe hallux valgus deformities. The subjects were asked to rate the deformity as "none," "mild," "moderate," or "severe." Using an externally mounted eye tracking system, our study assessed saccades, fixations, overall time spent per radiograph, and the subjects' chosen bunion rating. Both the novice and advanced groups of foot and ankle surgeons were tasked to evaluate 25 total anteroposterior radiographs from patients who presented with a primary complaint of bunion pain. These patients were chosen at random, such that all participating surgeons had no previous patient familiarization. Statistically significant differences were observed with regard to the activity and rating of the moderate bunion films. The experience of surgeons does appear to modify gaze behavior with respect to time and attention, such that less overall time spent per image is needed by the advanced group, with improved efficiency. Future academic curriculum and training techniques could be developed to reflect these potential technical differences in search behavior, diagnostic technique, and surgical selection strategy.

Hypermobility of the first metatarsal bone in patients with rheumatoid arthritis treated by Lapidus procedure

Background

Foot deformities and related problems of the forefoot are very common in patients with rheumatoid arthritis. The laxity of the medial cuneometatarsal joint and its synovitis are important factors in the development of forefoot deformity. The impaired joint causes the first metatarsal bone to become unstable in the frontal and sagittal planes. In this retrospective study we evaluated data of patients with rheumatoid arthritis who underwent Lapidus procedure. We evaluated the role of the instability in a group of patients, focusing mainly on the clinical symptoms and X-ray signs of the instability.

Methods

The study group included 125 patients with rheumatoid arthritis. The indications of the Lapidus procedure were a hallux valgus deformity greater than 15 degrees and varus deformity of the first metatarsal bone with the intermetatarsal angle greater than 15 degrees on anterio-posterior weight-bearing X-ray.

Results

Data of 143 Lapidus procedures of 125 patients with rheumatoid arthritis, who underwent surgery between 2004 and 2010 was evaluated. Signs and symptoms of the first metatarsal bone instability was found in 92 feet (64.3%) in our group. The AOFAS score was 48.6 before and 87.6 six months after the foot reconstruction. Nonunion of the medial cuneometatarsal joint arthrodesis on X-rays occurred in seven feet (4.9%).

Conclusion

The Lapidus procedure provides the possibility to correct the first metatarsal bone varus position and its instability, as well as providing the possibility to achieve a painless foot for walking. We recommend using the procedure as a preventive surgery in poorly symptomatic patients with rheumatoid arthritis in case of the first metatarsal bone hypermobility.