Abstract
Background
Patients with hallux valgus (HV) deformity often experience shoe-wearing discomfort, and increased foot width is considered a contributing factor. We assessed foot width using standing radiographs and 3-dimensional (3D) scans. This study aims to evaluate how these measurements are related to clinical outcomes in HV patients.
Methods
This cross-sectional study enrolled 19 consecutive adults presenting for hallux valgus evaluation. All participants underwent weight-bearing radiographs and 3D structured-light scanning, followed by completion of patient-reported outcome measures including pain visual analog scale, EuroQol 5-Dimension 5-Level (EQ-5D-5L), and Manchester-Oxford Foot Questionnaire (MOXFQ). Radiographic measurements included intermetatarsal angle, hallux valgus angle, bone width, and soft tissue width. 3D parameters included maximal and horizontal forefoot width, ball circumference, instep circumference, and ball-to-instep ratio. Pearson correlations and multivariable regression analyses examined relationships between morphological parameters and patient-reported outcomes.
Results
The cohort consisted of 14 women and 5 men with a median age of 57.0 years. Strong correlations were observed between radiographic and 3D measurements of bone and soft-tissue width (r = 0.93–0.97). The intermetatarsal angle showed moderate correlations with all 3D foot-width parameters (r = 0.54–0.65), while hallux valgus and interphalangeal angles did not demonstrate meaningful associations. In multivariable analyses, bone width was the predictor of MOXFQ-index scores and served as the predictor of social interaction difficulties. No dimensional parameters correlated with EQ-5D-5L scores. Domain-specific analysis revealed that bone width predicted social interaction problems, while maximal and horizontal width predicted walking/standing difficulties.
Conclusions
In hallux valgus patients, both radiographic bone width and 3D-scan-derived ball-to-instep ratio show notable associations with social interaction difficulties on the MOXFQ, highlighting the role of forefoot width in shoe wearing discomfort and patient-reported outcomes. Integrating these measurements into clinical evaluation may inform personalized footwear selection and design, such as wider toe boxes or customized last shapes, to alleviate symptoms and improve functional and social outcomes for patients with hallux valgus.
Keywords: Hallux valgus, Foot width, Three-dimensional imaging, Patient reported outcomes
Hallux valgus deformity is characterized by lateral deviation of the great toe and medial prominence of the first metatarsal head, resulting in a spectrum of symptoms such as forefoot pain, visible deformity and difficulty with footwear selection.1) Widening of the forefoot is associated with discomfort, particularly difficulties in shoe fitting and altered plantar pressure distribution, which together impair daily function and quality of life.2) Previous authors have noted correlations between changes in foot width and symptom severity, but these studies have almost exclusively used single-plane imaging modalities such as weight-bearing radiographs or computed tomography.3,4)
Conventional radiographic measures, including the intermetatarsal angle (IMA) and hallux valgus angle (HVA), focus on bony alignment and do not fully reflect the 3-dimensional (3D) morphology that may affect shoe fit and patient-reported outcome measures (PROMs).5) With the advent of 3D scanning technology, it has become possible to obtain accurate, automated measurements of external foot dimensions under physiologic loading, including various forefoot width indices and circumferential parameters.6)
In this study, we acquired weight-bearing foot shape data using 3D scanning and generated automatic dimensional and width indices. We then analyzed associations between these objective parameters and established clinical outcome scales from patient questionnaires. By comparing radiographic and scan-derived measurements, we aimed to determine whether volumetric metrics offer additional clinical value in understanding the functional and symptomatic burden of hallux valgus and to improve surgical planning and patient counseling. We hypothesized that 3D scan-based measurements would better reflect the morphological changes responsible for patient-reported symptoms than traditional single-plane methods.
METHODS
The Institutional Review Board of Gyeongsang National University Changwon Hospital approved the protocol (IRB No. 2024-06-001), and all patients provided written informed consent.
Study Population
This cross-sectional study enrolled consecutive adults who presented for evaluation of self-perceived hallux valgus between July 2024 and August 2024. All participants underwent weight-bearing foot radiographs and 3D structured-light scanning in a single session, then completed PROMs; pain visual analog scale (VAS), EuroQol 5-Dimension 5-Level (EQ-5D-5L),7) and Manchester-Oxford Foot Questionnaire (MOXFQ)-index and 3 domain scores.8) Exclusion criteria were prior foot surgery, first-metatarsal arthritis, arthrosis of the first tarsometatarsal joint, or inability to bear weight.
Radiographic and 3D Scanner Measurements
On weight-bearing anteroposterior radiographs, IMA, HVA, interphalangeal angle (IPA), bone width (maximal bony distance across the first metatarsal head), and soft-tissue width (maximal soft-tissue contour) were measured (Fig. 1). All radiographs were obtained with consistent patient positioning and imaging settings to ensure comparability. Two orthopedic surgeons (JA and GHJ) independently measured each radiologic parameter on Picture Archiving and Communication System (PACS) on 2 occasions, 2 weeks apart, and the mean of their measurements was used for analysis. Inter- and intraobserver reliability for these radiographic measurements was evaluated using intraclass correlation coefficients (ICCs), with ICC ≥ 0.90 indicating excellent agreement. For 3D structured-light scanning, each subject stood barefoot on a rotating platform of a structured-light foot scanner (MediACE-Scan, RealDimension); alternating light-stripe patterns were projected onto the surface while a camera completed a 360° sweep to generate a dense point cloud. Proprietary software then automatically quantified maximal and horizontal forefoot width, ball circumference, and instep circumference (Fig. 2). The ball-to-instep ratio was calculated as ball circumference divided by instep circumference.
Fig. 1. Radiographic measurements of hallux valgus. (A) Anteroposterior weight-bearing radiograph demonstrating hallux valgus assessment. White solid lines indicate intermetatarsal angle, hallux valgus angle, and interphalangeal angle. (B) Anteroposterior weight-bearing radiograph showing measurement of foot width. White parallel lines represent the maximal bony and soft-tissue width.
Fig. 2. Three-dimensional structured-light scan measurement. (A) Dorsal view showing maximal forefoot width and horizontal forefoot width. The white dotted line indicates the ball circumference. Vertical lines indicate reference boundaries for width measurement. (B) Lateral view demonstrating measurement of foot length and instep height. White dotted ovals indicate the instep circumference and ball circumference measurements used to calculate the ball-to-instep ratio.
Statistical Analysis
Continuous variables were assessed for normality using the Shapiro-Wilk test and summarized using medians and interquartile ranges (IQRs) due to non-normal distributions. Categorical variables were summarized using frequencies and percentages. Pearson ICCs were calculated to explore relationships between radiographic and 3D scanner measurements, and between these objective measurements and PROMs, including the pain VAS, EQ-5D-5L, and MOXFQ-index and domain scores.
For multivariable modeling, all 7 candidate predictors (bone width, soft tissue width, 3D maximum width, 3D horizontal width, ball circumference, instep circumference, and ball-to-instep ratio) were first screened in univariable linear regression analyses. Predictors with a univariable p < 0.10 were entered into an initial multivariable model. A backward elimination procedure, with removal of variables at p > 0.05, was then applied to derive the final set of independent predictors for each PROM. Multicollinearity was evaluated using variance inflation factors (VIF), and any predictor with VIF > 5 was excluded to ensure model stability. Final regression coefficients are presented as standardized β values with corresponding p-values. All statistical analyses were conducted using Python (version 3.10) with the statsmodels (v0.14.0) and pandas (v2.2.1) libraries.
RESULTS
Nineteen participants (14 women; median age, 57.0 years [IQR, 46.0–62.0]; median BMI, 22.2 kg/m2 [IQR, 19.1–24.8 kg/m2]) completed radiographs, 3D scans, and PROMs in a single visit (Table 1). On weight-bearing anteroposterior radiographs, the median IMA was 12.0° (IQR, 10.0°–15.5°), HVA 28.0° (22.0°–31.0°), and interphalangeal angle 10.0° (9.0°–12.0°). Bone width measured 87.9 mm (86.3–89.8 mm) while soft-tissue width was 99.8 mm (96.7–101.7 mm). The 3D scanning yielded a median maximal forefoot width of 101.9 mm (98.1–103.8 mm), horizontal width 97.0 mm (93.2–99.1 mm), ball circumference 241.5 mm (234.4–248.0 mm), instep circumference 236.7 mm (229.8–246.1 mm), and a ball-to-instep ratio of 1.020 (0.993–1.049) (Table 2).
Table 1. Baseline Characteristics.
| Variable | Value (n = 19) | |
|---|---|---|
| Age (yr) | 57.0 (46.0–62.0) | |
| Height (cm) | 158.0 (156.6–162.0) | |
| Weight (kg) | 54.0 (48.2–64.2) | |
| Body mass index (kg/m2) | 22.2 (19.1–24.8) | |
| Body fat percentage (%) | 29.1 (20.8–31.0) | |
| Sex | ||
| Female | 14 (73.7) | |
| Male | 5 (26.3) | |
| Side | ||
| Left | 9 (47.4) | |
| Right | 10 (52.6) | |
Values are presented as median (interquartile range) or number (%).
Table 2. Summary of Simple Radiograph Measurements, 3D Scan Measurements, and Clinical Outcomes.
| Variable | Study population | |||
|---|---|---|---|---|
| Simple radiograph measurements | ||||
| Intermetatarsal angle (°) | 12.0 (10.0–15.5) | |||
| Hallux valgus angle (°) | 28.0 (22.0–31.0) | |||
| Interphalangeal angle (°) | 10.0 (9.0–12.0) | |||
| Bone width (mm) | 87.9 (86.3 – 89.8) | |||
| Soft-tissue width (mm) | 99.8 (96.7–101.7) | |||
| 3D scan measurements | ||||
| Foot length (mm) | 240.3 (232.1–245.3) | |||
| Maximum width (mm) | 101.9 (98.1–103.8) | |||
| Horizontal width (mm) | 97.0 (93.2–99.1) | |||
| Instep height (mm) | 64.6 (61.7–66.4) | |||
| Ball circumference (mm) | 241.5 (234.4–248.0) | |||
| Instep circumference (mm) | 236.7 (229.8–246.1) | |||
| Ball-to-Instep ratio | 1.020 (0.993-1.049) | |||
| Clinical outcomes | ||||
| Pain VAS (0–10) | 1.0 (1.0–1.5) | |||
| EQ-5D-5L | 0.816 (0.787–0.849) | |||
| MOXFQ-Index | 26.6 (25.0–34.4) | |||
| Pain | 32.5 (22.5–42.5) | |||
| Walking/standing | 23.2 (16.1–39.3) | |||
| Social interaction | 31.2 (25.0–37.5) | |||
Values are presented as median (interquartile range).
3D: 3-dimensional, VAS: visual analog scale, EQ-5D-5L: EuroQol 5-Dimension 5-Level, MOXFQ: Manchester–Oxford Foot Questionnaire summary index and domains.
Pearson ICCs indicated excellent agreement between radiographic and 3D measurements of bone width and soft-tissue width (r = 0.93–0.97, p < 0.001). The IMA exhibited significant moderate correlations with all 3D foot-width parameters—maximum width (r = 0.65, p = 0.003), horizontal width (r = 0.63, p = 0.004), ball circumference (r = 0.64, p = 0.003), and instep circumference (r = 0.54, p = 0.016)—whereas HVA and IPA did not demonstrate significant associations (r range = –0.44 to 0.03, p > 0.05), indicating that width-based and angular metrics assess distinct anatomical characteristics of hallux valgus (Table 3).
Table 3. Pearson Correlation Coefficients (r) and p-values between Simple Radiograph Measurements and 3D Scan Measurements.
| Radiograph measurement | Maximum width | Horizontal width | Ball circumference | Instep circumference |
|---|---|---|---|---|
| Intermetatarsal angle | 0.65 (0.003)** | 0.63 (0.004)** | 0.64 (0.003)** | 0.54 (0.016)* |
| Hallux valgus angle | 0.03 (0.890) | –0.02 (0.951) | 0.01 (0.969) | –0.06 (0.811) |
| Interphalangeal angle | –0.38 (0.107) | –0.44 (0.059) | –0.36 (0.128) | –0.38 (0.109) |
| Bone width | 0.97 (< 0.001)*** | 0.94 (< 0.001)*** | 0.96 (< 0.001)*** | 0.95 (< 0.001)*** |
| Soft-tissue width | 0.94 (< 0.001)*** | 0.93 (< 0.001)*** | 0.94 (< 0.001)*** | 0.96 (< 0.001)*** |
Values are Pearson r (p-value).
3D: 3-dimensional.
*p < 0.05, **p < 0.01, ***p < 0.01.
Univariable correlations with pain VAS were statistically significant for most predictors (r = 0.59–0.70, p ≤ 0.008), whereas ball-to-instep ratio fell short of significance (r = 0.35, p = 0.138) (Fig. 3). No predictor reached p < 0.10 for EQ-5D-5L (r = 0.09–0.29, p = 0.235–0.708). For the MOXFQ total index, 6 of 7 measures met the entry criterion (p < 0.10): bone width (r = 0.52, p = 0.023), soft-tissue width (r = 0.45, p = 0.054), 3D horizontal width (r = 0.44, p = 0.057), 3D maximum width (r = 0.42, p = 0.071), ball circumference (r = 0.41, p = 0.079), and ball-to-instep ratio (r = 0.39, p = 0.095); only instep circumference did not (r = 0.33, p = 0.170) (Table 4). Backward elimination retained 4 independent predictors of pain VAS—maximal width (β = –6.00, p = 0.002), horizontal width (β = 3.05, p = 0.003), instep circumference (β = 3.47, p = 0.008), and ball-to-instep ratio (β = 1.03, p = 0.005). For EQ-5D-5L, 5 variables remained significant (soft-tissue width, maximal width, ball circumference, instep circumference, and ball-to-instep ratio), and for the MOXFQ-index only bone width was retained (β = 2.16, p = 0.001) (Table 4).
Fig. 3. Heatmap of correlations between morphology and patient-reported outcomes. Pearson correlation coefficients between dimensional metrics and outcomes. Warmer colors indicate stronger positive correlations. 3D: 3-dimensional, VAS: visual analog scale, MOXFQ: Manchester-Oxford Foot Questionnaire.
Table 4. Univariable Correlation and Multivariable Regression of Radiographic and 3D Scan Measures for Patient-Reported Outcomes.
| Predictor | Pain VAS | EQ-5D-5L | MOXFQ-Index | |||
|---|---|---|---|---|---|---|
| Univariate | Multivariate | Univariate | Multivariate | Univariate | Multivariate | |
| Bone width | 0.59 (0.008) | - | 0.19 (0.440) | - | 0.52 (0.023) | 2.16 (0.001) |
| Soft-tissue width | 0.63 (0.004) | - | 0.09 (0.708) | –2.12 (0.002) | 0.45 (0.054) | - |
| 3D maximum width | 0.65 (0.003) | –6.0 (0.002) | 0.29 (0.235) | 6.16 (0.001) | 0.42 (0.071) | - |
| 3D horizontal width | 0.70 (0.001) | 3.05 (0.003) | 0.25 (0.293) | - | 0.44 (0.057) | - |
| 3D ball circumference | 0.68 (0.001) | - | 0.23 (0.342) | –26.42 (0.004) | 0.41 (0.079) | - |
| 3D instep circumference | 0.62 (0.005) | 3.47 (0.008) | 0.19 (0.433) | 21.71 (0.010) | 0.33 (0.170) | –1.73 (0.006) |
| Ball-to-instep ratio | 0.35 (0.138) | 1.03 (0.005) | 0.21 (0.393) | 5.27 (0.011) | 0.39 (0.095) | - |
Univariate β denotes Pearson correlation coefficient (r) with its p-value; Multivariate β denotes standardized regression coefficient (β) with its p-value.
All β values are reported to 2 decimal places and p-values to 3 decimal places. Variables not included in the final multivariate model are indicated by hyphens (-).
3D: 3-dimensional, VAS: visual analog scale, EQ-5D-5L: EuroQol 5-Dimension 5-Level, MOXFQ: Manchester–Oxford Foot Questionnaire summary index and domains.
In multivariable analyses of MOXFQ subscales (Table 5), a total of 7 candidate predictors were screened via univariable correlations (p < 0.10) before inclusion. For the Pain domain, 4 predictors emerged as independent determinants: greater bone width was associated with higher pain scores (standardized β = 8.37, p = 0.041), whereas each 1-standard-deviation increase in maximal forefoot width corresponded to an average 6.00-point reduction in reported pain (β = –6.00, p = 0.002). Horizontal width (β = 3.05, p = 0.003) and the ball-to-instep ratio (β = 1.03, p = 0.005) also contributed significantly. In contrast, only 2 variables—maximal width (β = –77.77, p = 0.018) and horizontal width (β = 48.20, p = 0.048)—remained predictive for the Walking/Standing domain. Notably, the Social Interaction domain was explained exclusively by bone width (β = 51.49, p < 0.001), with no 3D scan parameters retained, underscoring the dominant role of skeletal width in social discomfort associated with hallux valgus. Nonetheless, a supplemental scatterplot (Fig. 4) illustrates the unadjusted relationship between ball-to-instep ratio and the MOXFQ-social interaction score, demonstrating a moderate positive Pearson correlation (r = 0.45, p = 0.053). Although this association falls short of conventional significance, it suggests a trend toward a bivariate link between ball-to-instep ratio and patients’ perceived social impact of hallux valgus.
Table 5. Univariable Correlation and Multivariable Regression of Radiographic and 3D Scan Measures for MOXFQ Domains.
| Predictor | MOXFQ-pain | MOXFQ-walking/standing | MOXFQ-social interaction | |||
|---|---|---|---|---|---|---|
| Univariate | Multivariate | Univariate | Multivariate | Univariate | Multivariate | |
| Bone width | 0.47 (0.041) | 8.37 (0.041) | 0.49 (0.032) | 38.67 (0.014) | 0.49 (0.033) | 51.49 (< 0.001) |
| Soft-tissue width | 0.40 (0.092) | - | 0.44 (0.061) | - | 0.43 (0.066) | - |
| 3D maximum width | 0.42 (0.075) | - | 0.40 (0.088) | 6.16 (0.001) | 0.37 (0.120) | - |
| 3D horizontal width | 0.41 (0.080) | - | 0.44 (0.061) | –77.77 (0.018) | 0.38 (0.109) | - |
| 3D ball circumference | 0.40 (0.088) | - | 0.40 (0.091) | - | 0.36 (0.130) | - |
| 3D instep circumference | 0.31 (0.199) | - | 0.35 (0.144) | - | 0.26 (0.281) | –43.72 (< 0.000) |
| Ball-to-instep ratio | 0.44 (0.060) | - | 0.24 (0.313) | - | 0.45 (0.053) | - |
Univariate β denotes Pearson correlation coefficient (r) with its p-value; Multivariate β denotes standardized regression coefficient (β) with its p-value.
All β values are reported to 2 decimal places and p-values to 3 decimal places. Variables not included in the final multivariate model are indicated by hyphens (-).
3D: 3-dimensional, MOXFQ: Manchester–Oxford Foot Questionnaire summary index and domains.
Fig. 4. Correlation between ball-to-instep ratio and Manchester-Oxford Foot Questionnaire (MOXFQ) social interaction domain. Scatterplot with a linear regression line (red). Each “×” represents 1 patient (r = 0.45, p = 0.053).
DISCUSSION
This study demonstrates meaningful correlations between 3D foot morphometry and PROMs in hallux valgus, with multivariable analyses revealing distinct patterns of association across different symptom domains. Our findings indicate that bone width was the sole predictor of MOXFQ-index scores, while multiple 3D scan parameters contributed to pain assessment, suggesting that dimensional metrics capture different aspects of the hallux valgus symptom complex than traditional radiographic angular measurements.
Hallux valgus represents a multifaceted deformity that extends beyond simple angular malalignment, encompassing complex 3D morphological changes that impact patients’ daily functioning and footwear selection.9) Despite the prevalence and clinical relevance of hallux valgus, limited research has examined the relationship between objective 3D foot morphology and patient-reported symptom severity, particularly using validated outcome measures specifically designed for foot and ankle pathology. Previous investigations have predominantly relied on traditional radiographic angular measurements, which demonstrate good interobserver reliability for conventional parameters.10) However, previous studies examining correlations between radiographic parameters and PROMs have yielded inconsistent results, highlighting the need for alternative assessment approaches.11)
Structured-light scanning offers rapid, non-invasive, and highly accurate measurement of external foot dimensions, enabling assessment of complex morphological parameters that cannot be adequately captured through conventional radiography.12) The use of 3D modeling and computational anatomy in other orthopedic contexts further supports the broader clinical value of incorporating 3D-based morphometric evaluation.13) Our 3D scanning approach revealed several clinically relevant findings. The strong correlations between radiographic and 3D scan measurements validate the accuracy of structured-light scanning technology for morphometric assessment. Notably, the IMA showed moderate correlations with all 3D scan foot-width parameters, while HVA and interphalangeal angle did not demonstrate meaningful associations. This finding suggests that the IMA, which reflects metatarsal divergence, better correlates with 3D morphological changes than the HVA or IPA, indicating that metatarsal splaying may be more functionally relevant than hallux angulation alone.
The multivariable analyses demonstrated that 3D parameters provide unique predictive value for PROMs. Notably, different width measurements showed varying associations with pain VAS scores, though the clinical interpretation of these findings requires caution. The VAS represents a subjective measure that may reflect overall discomfort rather than specific pain mechanisms, and the observed relationships between dimensional parameters and VAS scores may be influenced by factors beyond pure morphological considerations. These findings suggest that the relationship between objective foot morphology and patient-perceived symptoms is less straightforward than previously understood and highlights the importance of using comprehensive outcome measures that capture different aspects of the patient experience.
Interestingly, bone width consistently emerged as a predictor across multiple outcome domains, while soft-tissue width showed limited predictive value. This differential finding may reflect the more stable and reproducible nature of skeletal measurements compared to soft-tissue dimensions, which can be influenced by various physiological and technical factors. The superior predictive value of bone width suggests that the underlying skeletal deformity, rather than secondary soft-tissue changes, may be the primary driver of patient-reported symptoms in hallux valgus. The superior predictive value of bone width aligns with, yet provides additional context to, previous findings in the literature. Ramachandran et al. reported conflicting associations between transverse osseous foot width and PROMs, with increased width correlating with worsening PROMs Measurement Information System physical scores but paradoxically better MOXFQ and VAS scores.11) The authors interpreted these contradictory findings as likely spurious due to their inconsistent nature. However, their analysis did not examine domain-specific MOXFQ subscales, particularly the social interaction domain which specifically addresses footwear-related difficulties and appearance concerns that are central to the patient experience in hallux valgus. Additionally, their study population consisted exclusively of patients scheduled for surgery, which may introduce selection bias toward more severe or refractory cases compared to our cohort of patients seeking initial evaluation. Our domain-specific analysis reveals that bone width serves as a strong predictor specifically for social interaction difficulties, suggesting that the relationship between skeletal prominence and PROMs may be more meaningful than previously recognized when examined through the lens of symptom-specific domains rather than composite scores.
The absence of meaningful correlations between our dimensional measurements and EQ-5D-5L scores warrants careful interpretation. The EQ-5D-5L is a well-validated instrument that has undergone extensive cultural adaptation across diverse populations worldwide.7) The lack of correlation in our study may reflect the inherently limited impact of hallux valgus on overall quality of life compared to more systemic conditions. Additionally, our study population consisted predominantly of mild to moderate deformity cases, which may not be severe enough to substantially affect the broader health domains captured by the EQ-5D-5L.
In contrast, the MOXFQ has undergone extensive validation for foot and ankle pathology and is widely considered among the most responsive instruments for hallux valgus assessment.8,14) The domain-specific analyses revealed particularly compelling patterns that provide insights into the nature of hallux valgus symptoms. Bone width serving as the exclusive predictor of social interaction scores highlights the profound psychological impact of visible deformity on patient well-being. This finding is noteworthy because the MOXFQ social interaction domain specifically addresses footwear-related concerns and appearance-related discomfort, suggesting that patients’ self-reported social difficulties are directly related to the most visible aspect of their deformity. The precise correspondence between objective skeletal prominence and subjective social concerns supports the clinical relevance of morphological assessments in understanding the patient experience beyond traditional pain and functional measures. The walking/standing domain showed a different pattern, with both maximal width and horizontal width emerging as predictors. This finding suggests that functional limitations during ambulation are more closely related to overall foot dimensions than to specific skeletal prominence, likely reflecting the consequences of altered foot shape on daily activities such as walking and standing.
The study limitations include the relatively small sample size, which constrains the generalizability of our findings and limits the power to detect smaller effect sizes. The cross-sectional design precludes assessment of causality and does not allow evaluation of changes over time or following treatment. Additionally, our patient population represented mild to moderate hallux valgus severity, and the relationships observed may not apply to patients with severe deformities or those with concurrent foot pathology. The single-institution recruitment may have introduced selection bias, as patients seeking evaluation at our clinic may not be representative of the broader hallux valgus population, potentially limiting the external validity of our findings. Despite these limitations, this preliminary investigation provides valuable insights into the relationships between 3D foot morphology and PROMs in hallux valgus. Our study employed precise 3D morphometric assessment combined with validated foot-specific outcome measures to examine the multifaceted nature of hallux valgus symptoms. The observed domain-specific correlations between dimensional parameters and different aspects of patient experience demonstrate the complexity of this condition and support the value of comprehensive morphological evaluation in understanding patient concerns beyond traditional radiographic assessment.
In conclusion, this study demonstrates that 3D foot morphometry, incorporating both radiographic bone width and 3D ball-to-instep ratio, provides clinically meaningful insights into the hallux valgus symptom complex beyond traditional angular measurements. Both bone width and ball-to-instep ratio are associated with social interaction difficulties on the MOXFQ, underlining the relevance of forefoot width in shoe wearing comfort and PROMs. Integrating these measurements into routine evaluation may inform personalized footwear selection and design, such as wider toe boxes or customized last shapes, to alleviate symptoms and improve functional and social outcomes for patients with hallux valgus.
ACKNOWLEDGEMENTS
This work was supported by the Korea Medical Device Development Fund grant funded by the Korea government (the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, the Ministry of Health & Welfare, the Ministry of Food and Drug Safety) (Project Number: RS-2022-00164554).
The authors acknowledge the use of ChatGPT 5 for English language editing assistance. All authors have contributed to the manuscript.
Footnotes
CONFLICT OF INTEREST: No potential conflict of interest relevant to this article was reported.
References
- 1.Colò G, Leigheb M, Surace MF, Fusini F. The efficacy of shoes modification and orthotics in hallux valgus deformity: a comprehensive review of literature. Musculoskelet Surg. 2024;108(4):395–402. doi: 10.1007/s12306-024-00839-9. [DOI] [PubMed] [Google Scholar]
- 2.Galica AM, Hagedorn TJ, Dufour AB, et al. Hallux valgus and plantar pressure loading: the Framingham foot study. J Foot Ankle Res. 2013;6(1):42. doi: 10.1186/1757-1146-6-42. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Ahn J, Jeong BO. Relationship between foot width reduction and clinical outcomes after chevron osteotomy for hallux valgus deformity. Clin Orthop Surg. 2023;15(1):159–165. doi: 10.4055/cios21272. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Conti MS, MacMahon A, Ellis SJ, Cody EA. Effect of the modified lapidus procedure for hallux valgus on foot width. Foot Ankle Int. 2020;41(2):154–159. doi: 10.1177/1071100719884556. [DOI] [PubMed] [Google Scholar]
- 5.Matthews M, Klein E, Youssef A, et al. Correlation of radiographic measurements with patient-centered outcomes in hallux valgus surgery. Foot Ankle Int. 2018;39(12):1416–1422. doi: 10.1177/1071100718790255. [DOI] [PubMed] [Google Scholar]
- 6.Rogati G, Leardini A, Ortolani M, Caravaggi P. Semi-automatic measurements of foot morphological parameters from 3d plantar foot scans. J Foot Ankle Res. 2021;14(1):18. doi: 10.1186/s13047-021-00461-z. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Kim SH, Ahn J, Ock M, et al. The eq-5d-5l valuation study in Korea. Qual Life Res. 2016;25(7):1845–1852. doi: 10.1007/s11136-015-1205-2. [DOI] [PubMed] [Google Scholar]
- 8.Schrier JC, Palmen LN, Verheyen CC, Jansen J, Koëter S. Patient-reported outcome measures in hallux valgus surgery. A review of literature. Foot Ankle Surg. 2015;21(1):11–15. doi: 10.1016/j.fas.2014.11.004. [DOI] [PubMed] [Google Scholar]
- 9.Lewis TL, Ray R, Gordon DJ. The impact of hallux valgus on function and quality of life in females. Foot Ankle Surg. 2022;28(4):424–430. doi: 10.1016/j.fas.2021.07.013. [DOI] [PubMed] [Google Scholar]
- 10.Lee KM, Ahn S, Chung CY, Sung KH, Park MS. Reliability and relationship of radiographic measurements in hallux valgus. Clin Orthop Relat Res. 2012;470(9):2613–2621. doi: 10.1007/s11999-012-2368-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Ramachandran SS, Reine S, Archer H, Koay J, Wukich DK, Chhabra A. Interreader reliability assessment of hallux valgus evaluation on dorsoplantar weightbearing radiographs from a prospective multi-center trial and correlation with patient-reported outcome measures. Skeletal Radiol. 2023;52(12):2419–2425. doi: 10.1007/s00256-023-04365-w. [DOI] [PubMed] [Google Scholar]
- 12.Farhan M, Wang JZ, Bray P, Burns J, Cheng TL. Comparison of 3D scanning versus traditional methods of capturing foot and ankle morphology for the fabrication of orthoses: a systematic review. J Foot Ankle Res. 2021;14(1):2. doi: 10.1186/s13047-020-00442-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Ahn J, Jeong SL, Jung GH. How to obtain the desired results from distal tibial nailing based on anatomy, biomechanics, and reduction techniques. J Musculoskelet Trauma. 2025;38(2):74–85. [Google Scholar]
- 14.Park MJ, Ko YC, Huh JW, Park SH, Park TH, Park JH. Validation of the Korean version of the Manchester-Oxford foot questionnaire in patients with hallux valgus. J Foot Ankle Surg. 2017;56(2):252–254. doi: 10.1053/j.jfas.2016.11.013. [DOI] [PubMed] [Google Scholar]