Evaluation of cosmetic shoulder balance in Lenke type 1 and 2 adolescent idiopathic scoliosis across different observational perspectives

Introduction

Adolescent idiopathic scoliosis (AIS) is a three-dimensional torsional spine deformity that leads to shoulder and trunk asymmetry (1,2). In addition to pain and reduced pulmonary function, perceivable shoulder imbalance is often a major concern for patients, adversely impacting their psychological health and self-evaluation of appearance (2-5). Regarding the evaluation of cosmetics by clinicians, previous studies have demonstrated a weak correlation between radiographic shoulder balance (Sh.B) and cosmetic Sh.B in patients with AIS, highlighting the importance of evaluation of cosmetic Sh.B for improving health-related quality of life (HRQoL) and enhancing surgical satisfaction (5-9). Despite comprehensive preoperative assessment of both radiological and cosmetic Sh.B, some patients with AIS still report residual cosmetic deformities and unsatisfactory improvement in self-perceived appearance postoperatively (6,10-12). Recent studies suggest that this discrepancy may be partially due to the inconsistency in observational viewpoints during cosmetic evaluation (13,14).

It has been reported that different viewing perspectives can lead to variability in the evaluation of clinical parameters, such as the cross-over sign of the acetabulum, and this may also occur for cosmetic evaluations (13-16). As outlined in previous work on research methodologies, clinical Sh.B evaluations are often conducted from a posterior perspective at the shoulder level (5-7,17). However, patients typically perform self-evaluation using mirrors from an anterior perspective at eye level (13). Although they cannot lower their gaze to shoulder level, this method reflects the patient’s authentic perception in daily life (13). Moreover, in clinical practice, despite most cosmetic Sh.B parameters being evaluated from a posterior perspective, differences in height between clinicians and patients may lead to misjudgments when different patients are measured from the same observational point. The potential inconsistency in height difference between clinicians and patients, along with the that between clinical and self-assessment perspectives, may affect the accuracy of cosmetic Sh.B evaluation. Despite this, there is a lack of research on whether different viewing perspectives affect cosmetic evaluation and on which viewing perspective produces cosmetic Sh.B evaluations with the strongest correlation with patient-reported outcomes (PROs). Clarifying these issues may optimize clinical decision-making.

The presence of the main thoracic or proximal thoracic curves in patients with Lenke type 1 or 2 AIS potentially increases the prominence of their shoulder imbalance (2,6); consequently, this study focused on patients with Lenke type 1 or 2 and sought to determine the following: (I) whether there are differences in cosmetic evaluations of Sh.B across different observational perspectives; and (II) the correlation between cosmetic measurements obtained from different perspectives and PROs. We present this article in accordance with the STROBE reporting checklist (available at https://qims.amegroups.com/article/view/10.21037/qims-2024-2873/rc).

Methods

Participants

This study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments and was approved by the institutional review board of Nanjing Drum Tower Hospital (No. 2021-LCYJ-DBZ-05). Informed consent was obtained from all patients’ legal guardians.

Patients with AIS who had undergone posterior spinal fusion between January 2022 and December 2022 were retrospectively reviewed. All radiographic data and photographic documentation were retrieved from the institutional clinical database. Due to the anatomical differences in the anterior and posterior trunk structures between males and females, particularly the breast development during female adolescence, this study exclusively included female patients. To minimize the potential confounding effects of obesity on cosmetic evaluation, patients with a body mass index (BMI) exceeding 25 kg/m² were excluded from the study (18). The inclusion and exclusion criteria are provided in Figure 1.

Figure 1 Flowchart of patient inclusion and exclusion. BMI, body mass index.

Data collection

Demographic information such as age, sex, and height were collected. The Scoliosis Research Society-22 (SRS-22) questionnaire was obtained preoperatively and at 2-year follow-up. All patients were required to receive a full-spine posterior-anterior X-ray preoperatively. Standing posteroanterior and lateral spinal radiographs were taken preoperatively, postoperatively, and at the 2-year follow-up, while clinical photographs were only obtained before preoperative radiographs. The process was conducted by an experienced technician with the approval of both the patients and their parents, with at least one parent being present during the procedure. The patients were photographed in a relaxed, neutral stance on level ground with their shoes removed. The technician stood at a fixed distance of 150 cm from the patient and took photographs from four observation points (Figure 2): point A, posterior shoulder level; point B, 20 cm above point A; point C, anterior shoulder level; and point D (20 cm above point C).

Figure 2 Diagram illustrating photographs taken from four observation points (point A: posterior shoulder level; point B: posterior eye level; point C: anterior shoulder level; point D: anterior eye level).

For radiographic shoulder and trunk balance, nine parameters were measured:

• Radiographic shoulder height difference (RSHD), which is the height difference between the soft tissue shadows above the bilateral acromioclavicular joints, with the left shoulder higher than the right shoulder being defined as positive (Figure 3A);
• First rib angle (FRA), which is the tilt of a tangential line connecting the highest points of the first ribs on both sides (Figure 3B);
• The clavicle-rib cage intersection (CRCI), which is the vertical height difference at the intersection of the clavicles and ribs on both sides (Figure 3C);
• The coracoid process height (CPH), which is the vertical height difference between the highest points of the coracoid processes on both sides, with the left coracoid process higher than the right being defined as positive (Figure 3D).
• T₁ tilt, which is the angle between a line though the upper endplate of T₁ and the horizontal line, with the vertebral body on the left side higher than the right being defined as positive (Figure 3E);
• Clavicle angle (CA), which is the angle between the horizontal line and the line connecting the highest points of the bilateral clavicles, with the left side higher than the right being defined as positive (Figure 3F);
• Clavicle-chest cage angle difference (CCAD), which is the difference in the angles between the vertical line through the centers of the T₁ and T₁₂ vertebral bodies and the lines connecting the midpoints of the proximal and distal ends of each clavicle (Figure 3G);
• Coronal balance distance (CBD), which is the horizontal distance between the C₇ plumb line (C₇PL) and central sacral vertical line (CSVL) (Figure 3H, green caption).
• The Cobb angle; which is the angle between the upper endplate of the upper end vertebra and the lower endplate of the lower end vertebra of the main curve (Figure 3H, white caption).

Figure 3 Radiographic parameters. (A) RSHD (the two white arrows indicate the horizontal lines passing through the soft tissue shadows superior to the acromioclavicular joints). (B) FRA. (C) CRCI (the two white arrows indicate the horizontal lines passing through the intersection between the clavicle and the outer face of the rib cage). (D) CPH (the two white arrows indicate the horizontal lines passing through the highest points of the coracoid processes). (E) T1 tilt. (F) CA. (G) CCAD. (H) CBD (the two green arrows respectively indicate the C7 plumb line and the CSVL) and Cobb angle (white). CA, clavicle angle; CB, coronal balance; CBD, coronal balance distance; CCAD, clavicle-chest cage angle difference; CPH, coracoid process height; CRCI, clavicle-rib cage intersection; CSVL, central sacral vertical line; FRA, first rib angle; RSHD, radiographic shoulder height difference; C7PL, C7 plumb line.

For Sh.B, six parameters were measured:

• Shoulder angle (α₁), which is the angle between the line connecting the shoulders and the upper arm turning points and the horizontal line, with the left shoulder higher than the right being defined as positive (Figure 4A);
• Axilla angle (α₂), which is the angle between the line connecting the bilateral axillae and the horizontal line, with the left axilla higher than the right being defined as positive (Figure 4B);
• Shoulder area index 1 (SAI₁), which is the ratio of the area above the axilla between the left and right sides of the back (refer to Figure 4C for details);
• Shoulder area index 2 (SAI₂), which is the ratio of the area above the shoulders between the left and right sides of the back (refer to Figure 4D for details); and
• Cosmetic shoulder height, which is further divided into outer shoulder height (SHo; refer to Figure 4E for details) and inner shoulder height (SHi; refer to Figure 4F for details).

Figure 4 Cosmetic parameters. (A) α₁. (B) α₂. (C) The area enclosed by the line connecting the inflection points between the neck and shoulders on both sides (L1), the horizontal line passing through the higher axilla (L2), the superior margins of the shoulders, with the outer margin of the upper arms being divided by a plumb line drawn through the midpoint of the neck into the left thoracic area (A1) and right thoracic area (A2). The ratio of A1 to A2 was defined as the SAI₁. (D) SAI₂: the area enclosed by L1 and the horizontal line passing through the lower inflection point between the shoulder and upper arm (L3), with the superior margins of the shoulders being divided by a plumb line drawn through the midpoint of the neck into the left shoulder area (B1) and right shoulder area (B2). SAI₂ is the ratio of B1 to B2. (E,F) A horizontal line is drawn across the higher axilla, intersecting the upper arm at points L (left) and R (right). The cervical midline intersects the horizontal line at point O. Trisection lines from O to L and O to R intersect the lateral and medial sides of the left shoulder at points A and B and the right shoulder at points A' and B'. The height difference between points A and A' is defined as SHo (the vertical distance between horizontal lines indicated by the two blue arrows), and the height difference between points B and B' is defined as SHi (the vertical distance between horizontal lines indicated by the two red arrows). α₁, shoulder angle; α₂, axilla angle; SAI₁, shoulder area index 1; SAI₂, shoulder area index 2; SHi, inner shoulder height; SHo, outer shoulder height.

The trunk appearance perception scale (TAPS) was also recorded. The TAPS assessment comprises three distinct visual perspectives of trunk deformity evaluation: posterior view, overhead view during forward bend test, and anterior view (with gender-specific illustrations). Each perspective is evaluated on a five-point scale, where 1 represents maximum deformity and 5 indicates minimal deformity. Patients select the illustrations that best correspond to their perceived body image, and the final score is calculated as the mean of these three ratings, yielding a comprehensive score between 1 and 5 (19).

The radiographic parameters were measured with Surgimap software (Nemaris Inc., New York, NY, USA), and the cosmetic parameters were measured using Image-Pro Plus 6.0 software (Media Cybernetics, Rockville, MD, USA). All radiographic and cosmetic parameters were independently measured by two experienced surgeons, and the average values were applied for further analysis.

Statistical analysis

All analyses were conducted using SPSS version 28 (IBM Corp., Armonk, NY, USA). Continuous variables with a normal distribution were compared between the two groups via t-tests and are presented as the mean ± standard deviation (SD). Pearson correlation coefficients were used to assess the relationship between cosmetic measurements obtained from different perspectives and preoperative SRS-22 scores, in addition to changes in SRS-22 scores from preoperation to 2-year follow-up. Intraclass correlation coefficients (ICCs) were used to evaluate the interobserver and intraobserver reliability of cosmetic measurements and radiographic measurements. The minimum detectable difference (MDD_95%) was calculated to examine clinical applicability. The Benjamini-Yekutieli method was applied to control the false-discovery rate (FDR) in comparisons. A P value <0.05 was considered statistically significant.

Results

Demographic and preoperative radiographic data

The preoperative demographic and preoperative radiographic data are shown in Table 1. In this study, 74 patients with AIS who underwent posterior spinal fusion were ultimately recruited, including 47 with Lenke type 1 and 27 with Lenke type 2. All patients were female, with a mean age of 14.5±1.9 years (range, 11–18 years), a mean Risser sign value of 2.7±1.0 (range, 1–5), and a mean follow-up duration of 27.0±1.7 months (range, 24–34 months). The mean preoperative height was 163.0±8.2 cm, and the mean weight was 47.8±8.0 kg. For preoperative radiographic trunk balance, the Cobb angle was 52.9°±10.0°, and the CBD was −1.0±17.2 mm. The radiographic Sh.B measurements yielded a preoperative RSHD of −2.2±12.1 mm, an FRA of −1.3°±4.7°, a CRCI of −4.5°±8.3°, a CPH of −1.4±10.9 mm, a T₁ tilt of 0.5°±6.9°, a CA of −0.7°±2.7°, and a CCAD of 2.3±10.3 mm. There were no significant statistical differences in preoperative demographic or radiographic measurements between the Lenke type 1 and Lenke type 2 groups.

The interobserver and intraobserver ICCs demonstrated robust reliability, ranging from 0.774 to 0.892 for cosmetic parameters and from 0.794 to 0.895 for radiographic parameters, indicating substantial agreement across all measurements (Table 2).

Cosmetic measurements obtained from four observation points

Cosmetic parameters related to angle (α₁ and α₂), height (SHo and SHi), and area (SAI₁ and SAI₂) were measured from four observation points (Figure 2 and Table 3), including two at the shoulder level (points A and C) and two 20 cm above the shoulders to simulate the patient’s eye level (points B and D).

Regardless of whether the evaluations were obtained from the anterior or posterior perspectives, there were significant statistical differences in angle-related and height-related cosmetic parameters between the different heights. The respective posterior cosmetic measurements for point A and point B were as follows: α₁, 1.77°±2.17° vs. 1.11°±1.59° (P=0.029); α₂, −3.12°±3.01° vs. −2.10°±3.22° (P=0.021); SHo, 0.20±1.73 vs. −0.19±1.44 cm (P=0.009); and SHi, 0.95±0.62 vs. 0.29±0.59 cm (P<0.001). Meanwhile, the respective anterior cosmetic measurements for point C and point D were as follows: α₁, 1.71°±2.02° vs. 1.13°±1.65° (P=0.022); α₂, −2.09°±3.20° vs. −1.71°±2.01° (P=0.029); SHo 0.19±1.29 vs. −0.18±1.35 cm (P=0.005); and SHi 0.89±0.88 vs. 0.30±0.59 cm (P<0.001).

When the measurements were obtained at the same level, only α₂ was significantly difference between the anterior and posterior perspectives (point A vs. point C: −3.12°±3.01° vs. −2.09°±3.20°, P=0.028; point B vs. point D: −2.10°±3.22° vs. −1.71°±2.01°, P=0.037), while the differences for α₂, SHo, SHi, SAI₁, and SAI₂ were not statistically significant.

The mean absolute values of all parameters with significant differences surpassed their corresponding MDDs, indicating clinically relevant changes (Table 4).

Correlation between cosmetic measurements and preoperative SRS-22 scores

The preoperative and 2-year follow-up SRS-22 scores for each domain are presented in Figure 5. Compared to the preoperative period, at the 2-year follow-up, the scores in all domains of the SRS-22 increased, with significant statistical improvements observed in pain scores (4.0±0.14 vs. 4.32±0.21; P=0.021), self-image scores (3.55±0.67 vs. 4.11±0.11; P=0.007), and mental health scores (4.48±0.11 vs. 4.67±0.18; P=0.029).

Figure 5 Comparison of SRS-22 outcome scores between groups. *, P value <0.05; **, P value <0.01. SRS-22, Scoliosis Research Society-22.

From the posterior perspective, when cosmetic parameters were obtained from the shoulder level, only α₂ demonstrated a significant negative correlation with the preoperative self-image domain (R=−0.218; P=0.032). However, at a higher level, α₁ (R=−0.217; P=0.032), α₂ (R=−0.229; P=0.025), and SHo (R=−0.207; P=0.038) demonstrated a significant negative correlation with the preoperative self-image domain. However, there were no significant correlations at the posterior shoulder level or eye level between any of the cosmetic parameters and the preoperative mental health domain.

Compared to posterior observation, anterior observation had more parameters correlated with the preoperative SRS-22 scores. Significant negative correlations with the preoperative self-image domain were observed for eye-level α₁ (R=−0.359; P=0.009), α₂ (R=−0.413; P=0.003), SAI₁ (R=−0.229; P=0.024), SAI₂ (R=−0.211; P=0.037), and SHo (R=−0.305; P=0.010), as well as for shoulder-level α₁ (R=−0.287; P=0.013), α₂ (R=−0.249; P=0.017), and SHo (R=−0.211; P=0.036). Moreover, significant negative correlations with preoperative mental health domain were also found eye-level α₁ (R=−0.391; P=0.007), α₂ (R=−0.361; P=0.009), SAI₁ (R=−0.233; P=0.021), and SHo (R=−0.266; P=0.015), as well as for shoulder-level α₁ (R=−0.282; P=0.014), α₂ (R=−0.225; P=0.027), and SHo (R=−0.219; P=0.030) (Table 5).

Correlation between cosmetic measurements and ΔSRS-22 scores during follow-up

Significant correlations with the Δself-image domain were observed for posterior shoulder-level α₁ (R=−0.219; P=0.030), α₂ (R=−0.237; P=0.019), SHo (R=−0.225; P=0.027), and SHi (R=−0.229; P=0.024); significant correlations with the Δmental-health domain were observed for α₁ (R=−0.199; P=0.041), SHo (R=−0.209; P=0.038), and SHi (R=−0.197; P=0.041); significant correlations with the Δfunction domain were observed for α₁ (R=0.225; P=0.028) and SHo (R=0.192; P=0.042); and significant correlations with the Δpain domain were observed for α₁ (R=0.187; P=0.045), α₂ (R=0.198; P=0.041), and SHo (R=0.225; P=0.028). At the higher level, SHi was significantly correlated with Δself-image domain (R=−0.192; P=0.042). From the anterior shoulder level, α₁ was correlated with both the Δself-image domain (R=−0.199; P=0.040) and Δmental-health domain (R=−0.187; P=0.045), SHo was correlated with both Δself-image domain (R=−0.188; P=0.045) and the Δpain domain (R=0.192; P=0.042), and SHi was correlated with the Δfunction domain (R=0.192; P=0.042) (Table 6).

Discussion

An accurate evaluation of the Sh.B is the prerequisite for successful surgical correction, especially for Lenke 1 and 2 curves (6,12,13). Given the disparities in radiographic examinations, patients perceived balance, and observed cosmetic abnormities from other individuals, the determination on Sh.B is clinically challenging (13,14). Although previous studies have emphasized the importance of combining preoperative radiographic and cosmetic Sh.B evaluations (17,20,21), the influence of different observational perspectives on cosmetic Sh.B evaluation has been largely overlooked, which may contribute to inconsistencies and potential inaccuracies in assessment outcomes (6,7,13). Our study is the first to demonstrates that cosmetic Sh.B measurements from different observation points vary and have distinct clinical significance. Anterior measurements at eye level better reflected the patient’s self-assessment, while improvements in SRS-22 scores from preoperative to 2-year follow-up demonstrated a stronger correlation with cosmetic parameters obtained from the posterior shoulder level, highlighting the necessity of incorporating multiperspective cosmetic assessments both pre- and postoperatively.

Shoulder cosmesis represents one of the most crucial components of overall cosmetic balance in patients with AIS (6,22). Since Qiu et al. first introduced cosmetic Sh.B parameters (6,7), this aspect has garnered heightened attention among spine surgeons in recent years, with some studies suggesting that cosmetic Sh.B more reliably reflects PROs, which are closely linked to surgical satisfaction (3,14). However, the assessment of Sh.B remains susceptible to various influences, with the observational perspective being particularly significant. Initially, clinicians often focus on cosmetic Sh.B from the posterior perspective (6), whereas patients typically prioritize anterior Sh.B (13). Given that anterior self-assessment represents patients’ genuine subjective perception, discrepancies in cosmetic Sh.B evaluation between the anterior and posterior perspectives may adversely impact the validity of those clinical assessments based exclusively on posterior observations. Moreover, discrepancies arise not only between anterior and posterior perspectives but also across different observational heights on the same side, presenting significant challenges to the accuracy and consistency of cosmetic Sh.B assessment. For instance, when patients perform self-assessments using a mirror, they cannot lower their observational perspective to shoulder level. Similarly, height differences between surgeons and patients also lead to discrepancies in observational height. However, it remains unclear whether these inconsistent observational perspectives result in inaccuracies in cosmetic Sh.B assessments, potentially influencing clinical treatment strategies. Therefore, further research regarding the effects these different perspectives on the assessment of cosmetic Sh.B is necessary.

Our study evaluated the cosmetic Sh.B of patients from four observation points, simulating both the eye level and shoulder level from the anterior and posterior perspectives (Figure 2). The primary finding of our study is that cosmetic measurements vary significantly depending on the observation point, particularly in angle-related (α₁ and α₂) and height-related (SHo and SHi) parameters. In our comparative analysis of the anterior and posterior perspectives demonstrated, the anterior α₂ angle was significantly smaller than was the posterior α₂ angle at the same observational level (Table 3). This discrepancy may be attributed to the female breast structure attenuating the asymmetry in axillary height when viewed anteriorly (23,24) (Figure 6). These findings are consistent with Yang et al.’s study, in which no significant correlation between anterior and posterior shoulder cosmesis was found (13). Additionally, in patients with Lenke type 2 curves, cosmetic Sh.B assessed anteriorly has a stronger association with radiographic Sh.B than does that observed posteriorly (10,13).

Figure 6 Radiographs and clinical photographs of a 16-year-old female patient with AIS and a Lenke 1 curve (A,B). From observation point A, the patient exhibited a significant α₂ angle of 7.9° (C). However, from observation point C, due to anterior chest wall deformity and elevated positioning of the right breast, the anterior α₂ measured only 1.6° (D). Consequently, despite notable a shoulder imbalance observed from the posterior perspective, the relatively level anterior α₂ contributed to a higher preoperative score in the self-evaluation domain of the Scoliosis Research Society-22 (4.1). AIS, adolescent idiopathic scoliosis; α₁, shoulder angle; α₂, axilla angle; SHi, inner shoulder height; SHo, outer shoulder height.

In the comparative analysis across different observation heights, angle-related parameters (α₁ and α₂) and height-related parameters (SHo and SHi) demonstrated more pronounced differences (Table 3). From the posterior perspective, when assessed at shoulder level, patients’ α₁, α₂, SHo, and SHi were significantly larger than those obtained at eye level. A similar pattern was also observed from the anterior perspective. These findings suggest that on the same side, cosmetic measurements obtained from higher observation points may underestimate the patient’s actual clinical Sh.B (Figure 7). Consequently, when female patients conduct self-evaluation using a mirror, they are limited to evaluating from eye level and are subject to the smaller shoulder imbalance. As a result, the PROs obtained under these conditions may be more favorable than are those estimated from the posterior shoulder-level perspective. Our subsequent correlation analysis further validated this hypothesis.

Figure 7 Radiographs and clinical photographs of a 15-year-old female patient with AIS with a Lenke 1 curve (A,B). From observation point A, the patient demonstrated significant shoulder imbalance with measurements of α₁ =6.9°, α₂ =−2.51°, SHo =3.1 cm, and SHi =2.8 cm (C). However, from observation point B, the degree of shoulder imbalance was underestimated, with measurements of α₁ =0°, α₂ =−2.1°, SHo =1.1 cm, and SHi =0.9 cm (D). AIS, adolescent idiopathic scoliosis; α₁, shoulder angle; α₂, axilla angle; SHi, inner shoulder height; SHo, outer shoulder height.

We further determined the correlation between cosmetic Sh.B from different observational perspectives and PROs (Tables 5,6). Preoperatively, although none of the cosmetic parameters showed a strong correlation (R>0.8) with the SRS-22 scores, most anterior cosmetic parameters exhibited statistically significant correlations with the SRS-22 scores for self-image and mental health, particularly when assessed from eye level (Table 5). Moreover, whether viewed from the posterior or anterior perspective, all observed cosmetic parameters were negatively correlated with scores in all SRS domains, indicating that a more severe shoulder imbalance, as reflected by these cosmetic indicators, was associated with poorer SRS-22 scores. The strongest correlation was observed for the a₂ from the anterior eye level (R=−0.413; P=0.003). This finding is consistent with the disparities in cosmetic assessments across various observational perspectives and suggests that for patient self-evaluation, assessments conducted from the anterior eye-level perspective more accurately reflect their real PROs. Ramsay et al. suggested that the majority of patients with AIS, particularly females, demonstrate heightened preoperative concern regarding anterior breast asymmetry, primarily focusing on bilateral discrepancies in size and height (25). Furthermore, inadequate correction or exacerbation of postoperative breast asymmetry significantly reduces surgical satisfaction (24,26). Lee et al. also demonstrated that cosmetic parameters derived from the anterior perspective are more reliable for evaluating clinical Sh.B and are closely associated with PROs (14).

At the 2-year follow-up, the SRS-22 scores for pain, self-evaluation, and mental health all showed significant improvement (Figure 5). Although the improvement in SRS-22 scores during follow-up also did not show a strong correlation with cosmetic parameters obtained from all observation points, a greater number of cosmetic parameters from the posterior perspective, particularly those assessed at the shoulder level, exhibited statistically significant correlations with ΔSRS-22 scores (Table 6). Moreover, patients with more severe preoperative shoulder imbalance exhibited less improvement in the more subjective domains of self-image and mental health. This may be because these patients underestimated the severity of their shoulder imbalance, believing they could achieve similar surgical outcomes as those in other patients with milder preoperative shoulder imbalance. Their higher preoperative expectations resulted in limited improvement in these two SRS-22 domains. Conversely, in the more objective indicators of pain and function, patients with more severe shoulder imbalance demonstrated greater improvement, suggesting that corrective surgery provides more significant enhancement to their daily lives.

As improving the patient’s self-perceived cosmetic appearance is the primary purpose of corrective surgery for AIS, it has been suggested that spine surgeons conduct comprehensive evaluations incorporating both the anterior and posterior perspectives, as well as multiple vertical observation points including eye-level and shoulder-level assessments, when formulating surgical strategies. For example, for patients with type 2 AIS who demonstrate shoulder imbalance from the posterior shoulder-level perspective but appear balanced from the anterior eye-level perspective, overcorrection of the main thoracic and proximal thoracic curves during surgery may achieve great Sh.B from posterior perspective but may result in a left shoulder elevation that patients perceive as a iatrogenic worsening of shoulder imbalance, adversely affecting self-perception and surgical satisfaction. Therefore, incorporating these discrepancies between different perspectives in cosmetic evaluation bears substantial clinical significance in improving patients’ self-perception.

There are several limitations to our study which should be addressed. First, due to the retrospective design, the assessments were conducted from only four observation points. Future research incorporating additional perspectives, such as lateral views, may provide a more comprehensive evaluation of cosmetic outcomes. Second, although photography is a commonly used method for assessing clinical cosmesis, it may still be inadequate for accurately depicting three-dimensional deformities. Third, as multiperspective photography was only obtained preoperatively, further investigation is needed to evaluate the correlation between multiperspective evaluations of cosmetic Sh.B and PROs postoperatively and during follow-up. Finally, due to the higher prevalence of AIS in the female population, this study included only female patients. Future studies should expand the sample size and perform case matching to further investigate the impact of different perspectives on cosmetic evaluation and surgical strategies.

Conclusions

Our study revealed significant differences in cosmetic Sh.B across various observation points in patients with Lenke 1 and 2 curves. Although cosmetic Sh.B measured from the anterior eye level underestimates the patient’s actual shoulder asymmetry, it more accurately reflects the patient’s authentic self-perception. Meanwhile, Sh.B evaluated from posterior shoulder level demonstrates a stronger correlation with changes in SRS-22 scores during follow-up. Therefore, we recommend that spine surgeons integrate Sh.B assessments from the anterior eye level and posterior shoulder level when developing surgical strategies.

Acknowledgments

None.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://qims.amegroups.com/article/view/10.21037/qims-2024-2873/rc

Funding: This work was supported by Nanjing Medical Science and Technology Development Foundation (No. ZKX22017 to Z.L.) and the Jiangsu Provincial Medical Innovation Center of Orthopedic Surgery (No. CXZX202214 to Y.Q.).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-2024-2873/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by institutional review board of Nanjing Drum Tower Hospital (No. 2021-LCYJ-DBZ-05) and informed consent was obtained from all patients’ legal guardians.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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