Introduction: Patients often present to the clinic with radiographs taken without weight bearing. However, weight-bearing radiographs are typically required for surgical planning, resulting in additional cost and radiation exposure.

Aim: This study aimed to evaluate the effect of weight-bearing X-ray imaging on angular measurements and clinical decision-making in patients with hallux valgus.

Materials and methods: Sixty-one feet from thirty-two patients presenting to our hospital in 2023–2024 were included. Hallux valgus angle (HVA) and intermetatarsal angle (IMA) measurements were compared between weight-bearing and non-weight-bearing radiographs. The association between these imaging differences and surgical decision-making was analyzed.

Results: HVA was significantly higher on non-weight-bearing radiographs, whereas IMA was significantly higher on weight-bearing radiographs (p=0.004 and p<0.001, respectively). Surgical planning differed between the two imaging modalities in only 2 of 61 feet (3.3%).

Conclusion: Despite measurable differences in angular values, non-weight-bearing radiographs can be reliably used for preoperative planning in most cases. Surgeons often base their decisions on experience and preferred techniques rather than small variations in measurements.

hallux valgus, imaging, preoperative planning, radiograph, weight bearing

Hallux valgus (HV) is a structural deformity of the first metatarsophalangeal joint, defined radiographically in the transverse plane. Although numerous objective parameters exist, the hallux valgus angle (HVA), intermetatarsal angle (IMA), and metatarsal-sesamoid position form the basis of most preoperative planning and postoperative assessment.‌^[1] HV is among the most common foot deformities, with a prevalence of 23% in adults under 65 years and 36% in those over 65 years.^[2]

Weight-bearing radiographs are considered the gold standard for evaluating symptomatic hallux valgus.^[3] However, in clinical practice, initial imaging is often performed without weight bearing. When a patient presents with non-weight-bearing radiographs, surgeons face a dilemma: relying on these images may affect decision-making, while repeating imaging increases radiation exposure. Repeated radiographs should be obtained only when they meaningfully contribute to patient management.^[4]

Most studies agree that radiological parameters differ between weight-bearing and non-weight-bearing ima-ging.^[5] However, findings regarding the clinical relevance of these differences remain inconsistent.^[3,6] In our clinic, patients initially undergo non-weight-bearing imaging, while weight-bearing radiographs are obtained only after a surgical decision is made.

This study aimed to determine whether radiographs taken with and without weight bearing influence angular measurements or surgical indications for osteotomy or soft-tissue procedures.

This was a single-center, retrospective, non-invasive study. Sixty-one feet from thirty-two patients who presented in 2023–2024 with a diagnosis of hallux valgus (ICD-10: M20.1) and symptoms lasting at least six months were included (Fig. 1). Twenty-four patients (75%) were female and eight were male.

Figure 1.

Photograph showing bilateral hallux valgus deformity in a study participant.

Figure 2.

Medullary axis lines used to measure the hallux valgus angle (HVA) and intermetatarsal angle (IMA).

Exclusion criteria included prior foot surgery, deformity related to previous fractures, and the absence of appropriate radiographs.

Non-weight-bearing radiographs lacked standardization. Weight-bearing anteroposterior radiographs were obtained with patients standing on a flat surface, both feet included on the same film, and an X-ray tube angle of approximately 15° (Fig. 2).

As shown in Table 1, HVA and IMA were measured using the hospital’s digital goniometric software. The HVA was defined as the angle between the axes of the first metatarsal and the proximal phalanx, while the IMA was defined as the angle between the axes of the first and second metatarsals.

Patients with hallux valgus interphalangeus were also identified. Surgical planning followed the hallux valgus treatment algorithm in Mann’s Surgery of the Foot and Ankle.^[7]

Descriptive data were presented as mean±SD, median (min–max), or percentages. The Kolmogorov–Smirnov test assessed normality. The paired Wilcoxon test was used for dependent quantitative variables, and the McNemar test for dependent qualitative variables. Analyses were performed using SPSS 28.0, with significance set at p≤0.05.

The mean age of the 32 patients was 39.3±20.7 years. The hallux valgus angle measured 29.0° (17–48) on non-weight-bearing radiographs and 27.2° (16–45) on weight-bearing radiographs, with significantly higher values observed in the non-weight-bearing images (p=0.004) (Fig. 3). The intermetatarsal angle (IMA) measured 11.0° (5–22) on non-weight-bearing radiographs and 12.4° (6–20) on weight-bearing radiographs, with significantly higher values found in the weight-bearing images (p<0.001) (Table 2, Fig. 4).

Figure 3.

Difference in hallux valgus angle (HVA) measurements between weight-bearing and non-weight-bearing radiographs.

Figure 4.

Difference in intermetatarsal angle (IMA) measurements between weight-bearing and non-weight-bearing radiographs.

Hallux valgus interphalangeus assessment did not differ between imaging modalities (Fig. 5).

Figure 5.

Comparison of HVA and IMA measurements and evaluation of hallux valgus interphalangeus with and without weight bearing.

Nine different surgical procedures were used in this study cohort. Surgical plans were identical between the two imaging types in 59 of 61 feet (96.7%) (Fig. 6). Only two feet (3.3%) required different procedures when decisions were based on weight-bearing vs. non-weight-bearing radiographs (Table 3).

Figure 6.

Distribution of surgical procedures performed in the study cohort.

Preoperative planning for hallux valgus traditionally relies on anteroposterior weight-bearing radiographs. When selecting a corrective procedure, factors such as deformity location, joint congruity, deformity severity, first tarsometatarsal joint laxity, and soft-tissue tension must be considered.^[7]

Several studies have shown that HVA and IMA differ between weight-bearing and non-weight-bearing radiographs. Shereff et al. reported inconsistent differences but concluded that weight-bearing radiographs were adequate for planning.^[8] Tanaka et al. noted significant increases in HVA and IMA under weight-bearing conditions in HV patients.^[3] Fuhrmann et al. observed increases in IMA with weight bearing but found HVA higher on non-weight-bearing images.^[9] Burg et al. reported no significant differences.‌^[6] Our findings align with studies showing higher HVA in non-weight-bearing films and higher IMA in weight-bearing films.

Reliability studies have shown high inter- and intraobserver agreement for HVA, IMA, and DMAA.^[10] Some authors report improved accuracy with computer-assisted measurement^[11], while others find no difference between manual and computerized techniques.^[12] All measurements in our study were performed using digital software.

Burg et al. also showed that surgical planning rarely changes based on imaging modality, likely because surgeons rely on familiar techniques and holistic evaluation rather than small angular variations.^[6] Similarly, despite significant differences in measurements, our study found no clinically meaningful impact on surgical decisions. Although statistically significant differences in HVA and IMA were observed between weight-bearing and non-weight-bearing radiographs, these variations rarely translated into changes in surgical planning. This finding suggests that many surgeons rely on a standardized or experience-based operative strategy rather than strictly on small angular differences when selecting a procedure. In contrast, in centers or among surgeons who adopt a more individualized approach, particularly in borderline deformities, weight-bearing radiographs may still provide additional value for fine-tuning surgical decision-making.

This study has several limitations, including its single-center retrospective design, modest sample size, and the lack of standardized non-weight-bearing radiographs. However, the use of non-standardized films may also reflect real-world clinical conditions.

Surgeons can reliably use non-weight-bearing radiographs when planning hallux valgus surgery. Although angular differences exist, they rarely alter clinical decision-making. Besides angular measurements, surgical planning should also consider joint congruence, arthritic changes, and first-ray hypermobility.

Ethical statement

• The authors declared that no clinical trials were used in the present study.
• The authors declared that no experiments on humans or human tissues were performed for the present study.
• The authors declared that no informed consent was obtained from the humans, donors or donors’ representatives participating in the study.
• The authors declared that no experiments on animals were performed for the present study.
• The authors declared that no commercially available immortalized human and animal cell lines were used in the present study.

Conflict of interest

The authors have declared that no competing interests exist.

Artificial Intelligence (AI) use

The authors accept full responsibility for the content of the manuscript, including the disclosure of any use of AI. No AI tools were used in the preparation of this manuscript.

Funding

No funding was reported.

Author contributions

GB: Conception and design of the study, data acquisition, radiographic measurements, and drafting of the manuscript; CK: Contribution to methodology, clinical evaluation, and interpretation of results; MFÇ: Data analysis, statistical evaluation, and preparation of tables and figures; LH: Literature review, manuscript editing, and critical revision for important intellectual content; RÖ: Supervision of the research process, surgical evaluation, final approval of the manuscript, and accountability for all aspects of the work. All authors read and approved the final version of the manuscript and agree to be accountable for all aspects of the work.

Author ORCIDs

Cihan Kırçıl https://orcid.org/0000-0001-9758-5778

Data availability

All of the data that support the findings of this study are available in the main text.