Background: The newly described anteroposterior "off-axis view" (OAV) radiograph might help detect a hallux valgus interphalangeus (HVI) deformity more precisely compared to anteroposterior standing radiographs. Methods: A radiographic assessment of HVI angles was performed using preoperative standing anteroposterior and OAV radiographs for 67 ft. Intra-and interobserver agreement for all angles and their correlation with HV severity were analyzed. Results: The proximal-to-distal phalangeal articular angle showed less intra-and interobserver variance (intraclass correlation coefficient: 0.825) than did the other angles. OAV radiographs showed less interobserver reliability than did standing radiographs. HVI was underestimated significantly, by up to 5 degrees, on standing radiographs compared to OAV radiographs (p < 0.001). The mean differences between OAV and standing radiographs were 3.7 degrees and 5.0 degrees for the proximal-to-distal phalangeal articular and hallux interphalangeal angles, respectively, and were more pronounced for moderate-to-severe HV deformities. Conclusion: Angular measurements of HVI on traditional anteroposterior standing radiographs are significantly smaller than on OAV radiographs. Furthermore, angular measurements on OAV radiographs are associated with higher interobserver reliability. The most precise angle representing an HVI deformity might be the proximal-to-distal phalangeal articular angle. Clinical Relevance: Our findings may facilitate preoperative decision-making for additional akin osteotomy in HV correction. (C) 2020 Published by Elsevier Ltd on behalf of European Foot and Ankle Society.

BACKGROUND The aim of the present prospective randomized study was to evaluate the long-term outcomes of minimally invasive chevron osteotomy as compared with open distal chevron osteotomy for the correction of hallux valgus deformity. METHODS A randomized controlled design was applied. The following parameters were assessed at 6 and 12 weeks, 9 months, and 5 years postoperatively: the American Orthopaedic Foot & Ankle Society (AOFAS) Forefoot Score, a visual analog scale (VAS) score for pain, and a patient-satisfaction score. In addition, several radiographic parameters for hallux valgus correction and joint degeneration were collected. Range of motion was also assessed. Thirty-nine of 47 feet were available for analysis at the time of the latest follow-up. RESULTS During the 5-year study period, the outcomes of the minimally invasive technique were comparable with those of the open technique. No significant differences were seen between the 2 groups within 5 years postoperatively in terms of clinical outcomes (VAS, AOFAS, satisfaction), radiographic outcomes, joint degeneration, or range of motion. CONCLUSIONS Five years after treatment, the outcome following minimally invasive distal chevron osteotomy is comparable with that for the open technique for hallux valgus surgery. LEVELS OF EVIDENCE Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

The purpose of this study was to compare a minimally invasive chevron osteotomy technique (MIS group) and the well-established open chevron technique (OC group) for correction of hallux valgus deformity.