Orthopedics

Feature Articles 

Correlation Between Facial Asymmetry, Shoulder Imbalance, and Adolescent Idiopathic Scoliosis

Jae-Young Hong, MD; Seung-Woo Suh, MD, PhD; Hitesh N. Modi, MS; Jae-Hyuk Yang, MD; Young-Chul Hwang, MD; Dong-Yul Lee, MD, PhD; Chang-Yong Hur, MD, PhD; Young-Hwan Park, MD

Abstract

We conducted a prospective cross-sectional study to examine the correlation between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis. Sixty-nine adolescent idiopathic scoliosis patients and 29 healthy volunteers were enrolled in this study. All patients underwent whole-spine standing anteroposterior radiographs and frontal cephalograms. Patients were divided into mild, moderate, and severe groups depending on Cobb angle (10°–25°, 25°–40°, and >40°, respectively). Facial measurements included maxilla height difference, ramus length difference, and anterior nasal spine-menton angle. Shoulder measurements included coracoid height difference, clavicular angle, clavicle-rib intersection difference, and radiographic shoulder height.

The anterior nasal spine-menton angle in the severe group (>40°) was higher than in the other groups ( P<.05), as was the clavicle-rib intersection difference ( P<.05). In addition, the magnitude of the curve showed a possible correlation with the anterior nasal spine-menton angle and clavicle-rib intersection difference in scoliosis patients ( r=0.433 and r=0.511, respectively). According to different curve patterns, the anterior nasal spine-menton angle and clavicle-rib intersection difference were significantly higher in the double thoracic group than in the other groups ( P<.05). In the correlation analysis, the ramus length difference and anterior nasal spine-menton angle had a possible correlation with the coracoid height difference, clavicular angle, radiographic shoulder height, and clavicle-rib intersection difference ( P<.05).

Drs Hong, Suh, and Yang, and Mr Modi are from the Scoliosis Research Institute, Department of Orthopedics, Drs Hwang and Lee are from the Department of Orthodontics, and Drs Hur and Park are from the Department of Spine Surgery, Korea University Guro Hospital, Seoul, South Korea.

Drs Hong, Suh, Yang, Hwang, Lee, Hur, and Park, and Mr Modi have no relevant financial relationships to disclose.

Adolescent idiopathic scoliosis is a 3-dimensional deformity of the spine characterized by deformation in the sagittal, frontal, and transverse planes, which can cause several problems associated with the faulty posture of patients. Many related deformities affect the level of satisfaction in adolescent idiopathic scoliosis patients, such as trunk asymmetry, shoulder imbalance, and leg-length discrepancy. 1–4

Orthodontists have taken specific interest in adolescent idiopathic scoliosis, reporting that children affected by scoliosis have more malocclusions. Authors have reported that idiopathic scoliosis may correlate indirectly with facial asymmetry or dental deviations in the transverse dimension. 5,6 In addition, general abnormalities associated with congenital scoliosis, including facial hypoplasia and defective dental occlusion, have also been reported. 7,8 Facial asymmetry is defined as curvatures in relation to the vertical axis of the face. Although facial asymmetry and malocclusion are treated as focal pathological states, these deformities can originate from a faulty posture of the trunk.

Shoulder imbalance in patients with a proximal thoracic curve has been discussed, and the inclusion of the proximal thoracic curve in the instrumented fusion of adolescent idiopathic scoliosis patients is often a difficult clinical decision, particularly when attempting to balance the shoulders. 9–11 In addition to trunk shift and rib hump, shoulder balance is a criterion used to evaluate the postoperative outcomes of spinal deformity surgery. Moreover, the appearance of the back and shoulders is important to adolescent idiopathic scoliosis patients, as well as to their families. 1,2,4,12 Shoulder balance is a key component to body posture in adolescent idiopathic scoliosis patients.

Increasing concern regarding facial appearance and shoulder balance has highlighted the importance of a systemic approach to adolescent idiopathic scoliosis. However, little data exists on adolescent idiopathic scoliosis patients with facial asymmetry and shoulder imbalance. Thus far, no relationship has been established between adolescent idiopathic scoliosis and the development of facial asymmetry or shoulder imbalance. The aim of this study was to determine the correlation between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis.

Sixty-nine…

Abstract

We conducted a prospective cross-sectional study to examine the correlation between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis. Sixty-nine adolescent idiopathic scoliosis patients and 29 healthy volunteers were enrolled in this study. All patients underwent whole-spine standing anteroposterior radiographs and frontal cephalograms. Patients were divided into mild, moderate, and severe groups depending on Cobb angle (10°–25°, 25°–40°, and >40°, respectively). Facial measurements included maxilla height difference, ramus length difference, and anterior nasal spine-menton angle. Shoulder measurements included coracoid height difference, clavicular angle, clavicle-rib intersection difference, and radiographic shoulder height.

The anterior nasal spine-menton angle in the severe group (>40°) was higher than in the other groups ( P<.05), as was the clavicle-rib intersection difference ( P<.05). In addition, the magnitude of the curve showed a possible correlation with the anterior nasal spine-menton angle and clavicle-rib intersection difference in scoliosis patients ( r=0.433 and r=0.511, respectively). According to different curve patterns, the anterior nasal spine-menton angle and clavicle-rib intersection difference were significantly higher in the double thoracic group than in the other groups ( P<.05). In the correlation analysis, the ramus length difference and anterior nasal spine-menton angle had a possible correlation with the coracoid height difference, clavicular angle, radiographic shoulder height, and clavicle-rib intersection difference ( P<.05).

Drs Hong, Suh, and Yang, and Mr Modi are from the Scoliosis Research Institute, Department of Orthopedics, Drs Hwang and Lee are from the Department of Orthodontics, and Drs Hur and Park are from the Department of Spine Surgery, Korea University Guro Hospital, Seoul, South Korea.

Drs Hong, Suh, Yang, Hwang, Lee, Hur, and Park, and Mr Modi have no relevant financial relationships to disclose.

Correspondence should be addressed to: Seung-Woo Suh, MD, PhD, Scoliosis Research Institute, Department of Orthopedics, Korea University Guro Hospital, 80 Guro-Dong, Guro-Gu, Seoul 152–703, South Korea (spine@korea.ac.kr).
Posted Online: June 14, 2011

Adolescent idiopathic scoliosis is a 3-dimensional deformity of the spine characterized by deformation in the sagittal, frontal, and transverse planes, which can cause several problems associated with the faulty posture of patients. Many related deformities affect the level of satisfaction in adolescent idiopathic scoliosis patients, such as trunk asymmetry, shoulder imbalance, and leg-length discrepancy. 1–4

Orthodontists have taken specific interest in adolescent idiopathic scoliosis, reporting that children affected by scoliosis have more malocclusions. Authors have reported that idiopathic scoliosis may correlate indirectly with facial asymmetry or dental deviations in the transverse dimension. 5,6 In addition, general abnormalities associated with congenital scoliosis, including facial hypoplasia and defective dental occlusion, have also been reported. 7,8 Facial asymmetry is defined as curvatures in relation to the vertical axis of the face. Although facial asymmetry and malocclusion are treated as focal pathological states, these deformities can originate from a faulty posture of the trunk.

Shoulder imbalance in patients with a proximal thoracic curve has been discussed, and the inclusion of the proximal thoracic curve in the instrumented fusion of adolescent idiopathic scoliosis patients is often a difficult clinical decision, particularly when attempting to balance the shoulders. 9–11 In addition to trunk shift and rib hump, shoulder balance is a criterion used to evaluate the postoperative outcomes of spinal deformity surgery. Moreover, the appearance of the back and shoulders is important to adolescent idiopathic scoliosis patients, as well as to their families. 1,2,4,12 Shoulder balance is a key component to body posture in adolescent idiopathic scoliosis patients.

Increasing concern regarding facial appearance and shoulder balance has highlighted the importance of a systemic approach to adolescent idiopathic scoliosis. However, little data exists on adolescent idiopathic scoliosis patients with facial asymmetry and shoulder imbalance. Thus far, no relationship has been established between adolescent idiopathic scoliosis and the development of facial asymmetry or shoulder imbalance. The aim of this study was to determine the correlation between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis.

Materials and Methods

Sixty-nine adolescent patients with idiopathic scoliosis were examined by a spine surgeon and an orthodontist in an outpatient clinic between 2007 and 2008. The study group comprised 13 boys and 56 girls with an average age of 13.7 years (range, 13–15.2 years). Inclusion criteria were age 13 years or older and no prior surgery. Patients younger than 13 years were excluded because of the difficulty in finding a reference line and the lack of a significant number of permanent teeth on the cephalogram. Twenty-nine healthy volunteers (10 boys and 19 girls; Cobb <10°) with an average age of 13.2 years (range, 12.7–14.8 years) were recruited to compare parameters with the adolescent idiopathic scoliosis group.

Both groups underwent whole-spine standing anteroposterior (AP) and lateral radiographs and frontal cephalograms. Frontal cephalograms were taken in the natural head position in a rigid cephalostat with a film-focus distance of 154 cm. The fluid level method was used to define the natural head position, and specially designed ear rods were adjusted vertically to avoid head rotation. 13 During radiograph exposure, the teeth were kept in the centric occlusion. For imaging of the gravity vertical, a plumb wire was suspended on the cephalostat in front of the film cassette. In addition, radiographic measures of facial asymmetry were recorded using the V-Ceph 4.0 (Cybermed Co Ltd, Seoul, South Korea). Two reference lines were used to determine facial parameters: a line connecting the crista galli and anterior nasal spine defined as the midsagittal line, and a horizontal reference line defined as a line perpendicular to the midsagittal line that passes through the crista galli (Figure ).

Facial Parameters. Maxilla Height Difference (MHD) Is the Difference Between the Vertical Distance from the Horizontal Reference Line (HRL) to the Jugular Process. Ramus Length Difference (RLD) Is the Difference Between the Vertical Distance from the Horizontal Reference Line to the Antegonion. Anterior Nasal Spine-Menton Angle (ANS-ME) Is the Angle Formed by the Midsagittal Line (MSL) and a Line Connecting the Anterior Nasal Spine and Menton.

Figure 1:. Facial Parameters. Maxilla Height Difference (MHD) Is the Difference Between the Vertical Distance from the Horizontal Reference Line (HRL) to the Jugular Process. Ramus Length Difference (RLD) Is the Difference Between the Vertical Distance from the Horizontal Reference Line to the Antegonion. Anterior Nasal Spine-Menton Angle (ANS-ME) Is the Angle Formed by the Midsagittal Line (MSL) and a Line Connecting the Anterior Nasal Spine and Menton.

Shoulder balance was evaluated from radiographs taken by 1 technician at a 180-cm standard distance using a standard technique and the same radiograph machine. Radiographs were taken in the standing position with patients’ arms by their sides parallel to the trunk. Patients’ upper extremities were supported by bilateral vertical bars to avoid positional variances between patients. The physicians at the adolescent idiopathic scoliosis clinic were informed of the position of the arms during the radiographic examination to prevent any misinterpretation of these radiographs. If any radiograph was suspicious for positional variance, it was excluded from the study. In addition, radiographic measures of deformity in the spine and shoulder were recorded using the PiViewSTAR (Infinitt, Seoul, South Korea).

Spinal measurements included curve magnitude, type of curve, apical and end vertebra of each curve, number of vertebrae affected, and direction of the curve. The patients were divided into mild, moderate, and severe groups according to Cobb angle (10°–25°, 25°–40°, and >40°, respectively). In addition, the patients were divided into thoracic main, thoracolumbar/lumbar main, and double thoracic groups based on the location of the main curvature. Following the location of the main curvature, thoracic curve was defined as the apex location between the T2 to T11/12 disks, and the thoracolumbar/lumbar curve was defined as the apex location between the T12 to L4 disks; a double thoracic curve was defined as a double curve separately.

Three measurements were taken on frontal cephalogram to determine facial asymmetry. 14,15 Shoulder imbalance measured on radiographs included the 3 parameters described previously by Bagó et al, 16 as well as the radiographic shoulder height. 9 These parameters were determined from the standing AP radiograph.

The facial parameters included (Figure ):

  • Maxilla height difference: difference between the vertical distances from the horizontal reference line to the jugular process.
  • Ramus length difference: difference between the vertical distances from the horizontal reference line to the antegonion.
  • Anterior nasal spine-menton angle: angle formed by the midsagittal line and a line connecting the anterior nasal spine and menton.

The shoulder parameters included:

  • Coracoid height difference: height difference between the horizontal lines that pass through the upper margin of each coracoid process (Figure ).
  • Clavicular angle: angle between a line connecting the highest points of the clavicle and horizontal plane (Figure ).
  • Clavicle-rib intersection difference: height difference between the horizontal lines passing thorough the point where the superior border of the clavicle intersects with the outer edge of the second rib on each side (Figure ).
  • Radiographic shoulder height: difference in the soft tissue shadow directly superior to the acromioclavicular joint on standing AP radiographs (Figure ).

Facial and shoulder measurements were carried out twice independently by 2 orthodontists (D.Y.L., Y.C.H.) with a 2-week interval to decrease intraobserver (inter- and intraclass correlation coefficients [ICCs], >0.93; 95% confidence interval [CI], 0.88–0.95) and interobserver error (ICCs, >0.90; 95% CI, 0.85–0.92), and 2 spine fellows (H.N.M., J.Y.H.) with intraobserver (ICCs, >0.94; 95% CI, 0.89–0.96) and interobserver error (ICCs, >0.91; 95% CI, 0.88–0.93). Negative values represent right facial or shoulder elevation, whereas positive values represent left elevation. The absolute values were used to examine any deviation from normal regardless of the direction of shoulder imbalance and facial asymmetry. Statistical analysis was performed to determine any significant differences between the groups as well as the correlation between parameters. All analyses were performed using SPSS version 13 (SPSS, Inc, Chicago, Illinois).

Results

The mean Cobb angle of the 69 patients was 35.35° (range, 11°–80°). Nineteen patients made up the mild group (6 boys and 13 girls), 27 made up the moderate group (5 boy and 22 girls), and 23 made up the severe group (2 boys and 21 girls). According to the location of the main curve, 17 patients had a double thoracic curve (2 boys and 15 girls), 31 had a thoracic main curve (8 boys and 23 girls), and 21 had a thoracolumbar/lumbar main curve (3 boys and 18 girls).

The parameters that implied facial asymmetry and shoulder imbalance were analyzed by the severity of the main curve. The mean anterior nasal spine-menton angle was significantly different between the 4 groups (analysis of variance [ANOVA], P<.05). The anterior nasal spine-menton angle of the severe group was higher than that of the other groups (control, mild, moderate) (Tukey’s Honestly Significant Difference post hoc test, P<.05) (Table ). However, the maxilla height difference and ramus length difference showed no significant difference between the 4 groups ( P>.05). The clavicle-rib intersection difference was significantly different between the 4 groups (ANOVA, P<.05). The clavicle-rib intersection difference of the severe group was higher than that of the other groups (control, mild, moderate) (Tukey’s Honestly Significant Difference post hoc test, P<.05) (Table ). Although coracoid height difference and radiographic shoulder height showed a higher value in the severe group than in the other groups, it was not statistically significant ( P>.05). Pearson’s correlation analysis suggested a possible correlation between the magnitude of the curve and the anterior nasal spine-menton angle and clavicle-rib intersection difference in adolescent idiopathic scoliosis patients ( r=0.433 and r=0.511, respectively) (Table ). However, other parameters did not show a correlation with the magnitude of the curve ( P>.05).

Mean Value of Facial Parameters

Table 1. Mean Value of Facial Parameters

Mean Value of Shoulder Parameters

Table 2. Mean Value of Shoulder Parameters

Correlation of Cobb Angle and Parameters

Table 3. Correlation of Cobb Angle and Parameters

An analysis of the results according to the curve pattern showed a significant difference in anterior nasal spine-menton angle between the groups (ANOVA, P<.05). The anterior nasal spine-menton angle of the double thoracic group was significantly higher than in the control, thoracic main, and thoracolumbar/lumbar main groups (Tukey’s Honestly Significant Difference post hoc test, P<.05) (Table ). There was a significant difference in the clavicle-rib intersection difference between the 3 groups (ANOVA, P<.05) (Table ). The mean clavicle-rib intersection difference in the double thoracic, thoracic main, thoracolumbar/lumbar main, and control groups was 15.78 mm, 3.51 mm, 4.70 mm, and 4.00 mm, respectively. The clavicle-rib intersection difference was significantly higher in the double thoracic group than in the other groups (Tukey’s Honestly Significant Difference post hoc test, P<.05). The other parameters were similar between the groups ( P>.05). In the correlation analysis between facial and shoulder parameters, ramus length difference and anterior nasal spine-menton angle had a possible correlation with coracoid height difference, clavicular angle, and radiographic shoulder height ( r=0.327, P=.006; r=0.247, P=.04; r=0.258, P=.033, respectively), and clavicular angle and clavicle-rib intersection difference ( r=.395, P=.011; r=.647, P=.001, respectively) (Table ). Figure shows the representative case.

Mean Value of Facial Parameters According to Curve Type

Table 4. Mean Value of Facial Parameters According to Curve Type

Mean Value of Shoulder Parameters According to Curve Type

Table 5. Mean Value of Shoulder Parameters According to Curve Type

Correlation Between Facial and Shoulder Parameters

Table 6. Correlation Between Facial and Shoulder Parameters

Radiographs of a 14-Year-Old Girl with a Double Thoracic Curve (Cobb Angle, 52°) Who Had Facial Asymmetry (maxilla Height Difference, 1.95 mm; Ramus Length Difference, 5.8 mm; Anterior Nasal Spine-Menton Angle, 5.69°) (A) and Shoulder Imbalance (coracoid Height Difference, 11 mm; Clavicular Angle, 1.9°; Clavicle-Rib Intersection Difference, 6.1 mm; Radiographic Shoulder Height, 6.4 mm) (B).

Figure 6:. Radiographs of a 14-Year-Old Girl with a Double Thoracic Curve (Cobb Angle, 52°) Who Had Facial Asymmetry (maxilla Height Difference, 1.95 mm; Ramus Length Difference, 5.8 mm; Anterior Nasal Spine-Menton Angle, 5.69°) (A) and Shoulder Imbalance (coracoid Height Difference, 11 mm; Clavicular Angle, 1.9°; Clavicle-Rib Intersection Difference, 6.1 mm; Radiographic Shoulder Height, 6.4 mm) (B).

Discussion

Musculoskeletal anomalies occur frequently in association with congenital scoliosis. Disorders, such as clubfoot, Sprengel deformity, Klippel-Feil deformity, developmental dysplasia of the hip, and upper- and lower-limb deformities, need to be evaluated and treated in congenital scoliosis patients. 7,8,17 Huggare et al 5 reported that dentofacial status was associated with adolescent idiopathic scoliosis patients who had been treated with a brace. Rotated orbital, maxillary, and mandibular planes, as well as lateral malocclusions, were also observed in idiopathic scoliosis patients. Lippold et al 6 found a potential correlation between idiopathic scoliosis and malocclusion, as well as between weak body posture and malocclusion. In addition, some reports cite a relationship between adolescent idiopathic scoliosis and shoulder balance. 9,18,19 However, although adolescent idiopathic scoliosis has become a component of many spine surgery practices, few reports exist on its related deformities to the extremities, such as facial and shoulder deformities.

In the past, mild facial asymmetry was disregarded because it was believed that the normal craniofacial skeleton had some asymmetry that was subclinical and could be compatible with a normal dental occlusion. 20 Recently, it has become possible to detect mild facial asymmetry due to increasing concern regarding facial appearance and the development of digital imaging systems. In addition, shoulder imbalance becomes a significant factor in the treatment of scoliosis, as well as the curvature itself. Therefore, systematic studies regarding the related deformities of adolescent idiopathic scoliosis will be needed. The possibility of systematic relationships can alter the clinical attitude of physicians in the treatment of adolescent idiopathic scoliosis. Therefore, to find possible relationships, we analyzed the parameters of shoulder and facial asymmetry in adolescent idiopathic scoliosis patients.

A number of factors determine the facial asymmetry. 14,15 A distortion of the mandible, the maxilla, and other portions of the face can produce facial asymmetry. The present study evaluated 3 parameters and found that the anterior nasal spine-menton angle was significantly different in the severe scoliosis and double thoracic groups. The anterior nasal spine-menton angle indicates the deviation of the menton from the midsagittal line of the face. This value represents the angular distortion of the mandible from the vertical plane and can be a significant parameter in determining facial asymmetry. Although facial asymmetry includes a distortion of the entire face, it appears that there is some relationship between facial asymmetry and adolescent idiopathic scoliosis. Clinically, the severe scoliosis or double thoracic groups may have a higher prevalence of facial asymmetry. Therefore, in the treatment of adolescent idiopathic scoliosis patients, physicians must consider that these types of scoliosis can accompany facial asymmetry. Orthopedic surgeons must also consider the assessment of facial asymmetry with orthodontists in severe and double thoracic scoliosis. For a better treatment outcome, these systemic considerations can be important.

In this study, the anterior nasal spine-menton angle was significantly higher in the severe scoliosis group than in the control group, but the difference was small (1.44° vs 2.95°, respectively). Facial asymmetry can also be found in the normal population, and small differences can be taken as a normal variation. However, we found a statistically significant difference between the control (normal) and severe groups ( P<.05). The cephalograms were taken with the head in the natural position with fluid-level control, as well as specially designed ear rods adjusted vertically to take into account the habitual head tilt. Proper placement of the skull is essential for making a true interpretation of the facial structure. These small values will be significant if accurate measurements are carried out under strictly controlled conditions, which is also supported by the literature. 21–23 In addition, in the orthodontic field, these small differences can cause complications such as malocclusion and facial asymmetry. In contrast to the orthopedic field, even a difference of 1° can cause asymmetry in the orthodontic field. 21,23 The outcome of surgery in the orthodontic field commonly depends on correction of this small angle. Therefore, we consider this small difference significant.

Some authors have reported that shoulder balance plays an important role in the appearance of adolescent idiopathic scoliosis patients. 3,9,19 The left shoulders are often elevated in adolescent idiopathic scoliosis patients with double thoracic curves with a positive T1 tilt. Elevation of shoulder balance in adolescent idiopathic scoliosis patients with a double thoracic curve is important for decision making by most spine surgeons, as well as for evaluating the clinical outcome. Shoulder balance is an important indication to decide whether to instrument up to the proximal thoracic curve. 9–11 To quantify shoulder balance, Bagó et al 16 examined the relationship between shoulder height and radiographic parameters. They reported 4 radiographic measurements to estimate shoulder height in scoliosis. In other studies, many radiographic parameters have been used to evaluate shoulder balance, including T1 tilting, unelevated first rib, clavicle angle, and radiographic shoulder height. 9,18,19 We also used 4 of these parameters.

In our study, the severity of the main curve was related to the clavicle-rib intersection difference. The clavicle-rib intersection difference was significantly higher in the double thoracic group than in the thoracic main, thoracolumbar/lumbar main, and control groups. The clavicle-rib intersection difference is the height difference between the horizontal lines passing thorough the point where the superior border of the clavicle intersects with the outer edge of the second rib on each side. It is an important parameter representing shoulder balance. Although not all the parameters that represent shoulder balance were significantly different, there is a possible relationship between the magnitude or type of curve and shoulder imbalance.

Although the difference in clavicle-rib intersection difference between the groups was small (15.78, 3.51, 4.70, and 4.00 in double thoracic, thoracic main, thoracolumbar/lumbar main, and control, respectively), Kuklo et al 9 defined shoulder imbalance as a =10-mm difference between the shoulder heights, and Akel et al 18 reported the cut-off values that can differentiate clinically above and below a 10-mm difference between shoulders for each radiological parameter. Therefore, despite the small differences, shoulder imbalance was significantly higher in the severe scoliosis and double thoracic groups than in the other groups. Clinically, the severe scoliosis or double thoracic groups may have a higher prevalence of shoulder imbalance. Therefore, in the treatment of adolescent idiopathic scoliosis patients, physicians must consider that these types of scoliosis can accompany shoulder imbalance. In correction surgery, surgeons must consider the correction of shoulder imbalance as well as correction of the curvature itself in severe or double thoracic scoliosis.

Goldberg et al 24 suggested the hypothesis of adolescent idiopathic scoliosis as a whole-body problem. They reported that developmental instability may result in a loss of symmetry in growth and that the presence of an increased developmental left-right asymmetry may be a main cause of scoliosis. Whole-body asymmetry is related to scoliosis development, and the pathogenesis of adolescent idiopathic scoliosis can be developmental asymmetry. In another study, Goldberg et al 25 reported asymmetries in palmar dermatoglyphics and the brain in adolescent idiopathic scoliosis patients. They concluded that patients with adolescent idiopathic scoliosis showed generalized asymmetry of many functions and structures. They also proposed examination at the level of morphology and development of the whole body in adolescent idiopathic scoliosis. 26,27

A general assumption exists that the central sacral line bisects the trunk into 2 halves with similar shape and function. Asymmetry in any portion of the body can cause some imbalance in the whole body. Spinal deformities not only distort the vertebral alignment, but may also result in facial, shoulder, rib cage, and waist line asymmetry. Deformities of the spinal column may cause not only facial asymmetry, but also shoulder imbalance. However, no reports clearly determine the relationship between these deformities. Establishing a relationship between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis is equally important in the treatment of these patients. Our study is the first to analyze the possible relationships between shoulder and facial asymmetry in adolescent idiopathic scoliosis. In our study, Pearson’s correlation analysis showed a relationship between facial and shoulder parameters. Ramus length difference and anterior nasal spine-menton angle were associated with coracoid height difference, clavicular angle, radiographic shoulder height, and clavicle-rib intersection difference. These results suggest a possible relationship between the facial asymmetry and shoulder imbalance in adolescent idiopathic scoliosis. Although not all the parameters that represent facial asymmetry and shoulder balance were significantly related, and the correlation coefficient was not strong enough to confirm a positive relationship, there was a possible relationship between deformities of the trunk and face. In addition, in the severe scoliosis group, anterior nasal spine-menton angle and clavicle-rib intersection difference were higher than others in a similar pattern. In the double thoracic group, a similar pattern of difference was found in these parameters. It appears that there is some relationship between facial and shoulder asymmetry.

Accordingly, deformities of the spinal column can cause not only facial asymmetry, but also shoulder imbalance. These findings can provide a clinical clue for orthopedic surgeons and should be taken into account during the treatment of scoliosis patients. A systemic review of other extremities in the adolescent idiopathic scoliosis patient is important because severe curvature commonly accompanies the other deformities such as facial asymmetry and shoulder imbalance. Regarding the type of curve, double thoracic curvature also can accompany these deformities. Therefore, surgeons should examine the related facial or shoulder asymmetry in the treatment of severe or double thoracic adolescent idiopathic scoliosis. This possible relationship can influence the clinical decision in treatment of adolescent idiopathic scoliosis and can improve the treatment outcome. Adolescent idiopathic scoliosis is not a focal spinal disease but 1 part of the spectrum of whole-body asymmetry. Systemic consideration is important in treatment of adolescent idiopathic scoliosis. Facial asymmetry has received little attention in adolescent idiopathic scoliosis patients. This may in part result from the impression of independent facial pathologic conditions rather than a deformity related to other asymmetries. Although shoulder imbalance has been investigated in the literature, no reports have studied the possible systemic relationships with other deformities.

A strength of our study is that it is the first study to correlate facial asymmetry with adolescent idiopathic scoliosis and shoulder imbalance. However, the study could not evaluate the clinical data regarding facial asymmetry and shoulder imbalance. The clinical features of this deformity could be different from the radiological evaluations. Further study is warranted to compare the radiologic and clinical findings. Although we have experienced several congenital scoliosis patients with other anomalies, including facial, we only analyzed facial asymmetry in idiopathic scoliosis patients. To clarify the origin and differences of the facial asymmetry, another study is warranted. However, it appears that some characteristics of facial asymmetry found in adolescent idiopathic scoliosis are simple imbalances with no related deformities. This is different from genetic deformity with congenital scoliosis, which is commonly combined with clubfoot, Sprengel deformity, Klippel-Feil deformity, developmental dysplasia of the hip, and upper- and lower-limb deformities. 7,8,17 Although this study found some significant relationships in the parameters using strict methods by several surgeons to obtain reliable data, and these findings and methods are supported by the literature, 9,18,21–23 the difference between the parameters was small and can be different in clinical assessment.

Our study population was relatively small, with difference of sex ratios between each group. However, 90% power was achieved with our study population in power analysis of anterior nasal spine-menton angle, which shows the small difference. We analyzed the result using strict statistical methods with repeated accurate measurements. Although we cannot establish the clinical relevance with these small differences, it can provide a new concept in the treatment of adolescent idiopathic scoliosis that can encourage further study.

Conclusion

This study found a correlation between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis. Anterior nasal spine-menton angle and clavicle-rib intersection difference was higher in the severe scoliosis and double thoracic groups than in the other groups. In addition, Pearson’s correlation analysis revealed a possible correlation between the facial and shoulder parameters. Therefore, in the treatment of adolescent idiopathic scoliosis, surgeons should consider systemic-related anomalies such as facial and shoulder asymmetry.

References

  1. 1. Asher M, Min Lai S, Burton D, Manna B. The reliability and concurrent validity of the scoliosis research society-22 patient questionnaire for idiopathic scoliosis. Spine (Phila Pa 1976). 2003; 28(1):63–69. doi: 10.1097/00007632-200301010-00015 [CrossRef]
  2. 2. Iwahara T, Imai M, Atsuta Y. Quantification of cosmesis for patients affected by adolescent idiopathic scoliosis. Eur Spine J. 1998; 7(1):12–15. doi: 10.1007/s005860050020 [CrossRef]
  3. 3. Raso VJ, Lou E, Hill DL, Mahood JK, Moreau MJ, Durdle NG. Trunk distortion in adolescent idiopathic scoliosis. J Pediatr Orthop. 1998; 18(2):222–226. doi: 10.1097/00004694-199803000-00017 [CrossRef]
  4. 4. Theologis TN, Jefferson RJ, Simpson AH, Turner-Smith AR, Fairbank JC. Quantifying the cosmetic defect of adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 1993; 18(7):909–912. doi: 10.1097/00007632-199306000-00016 [CrossRef]
  5. 5. Huggare J, Pirttiniemi P, Serlo W. Head posture and dentofacial morphology in subjects treated for scoliosis. Proc Finn Dent Soc. 1991; 87(1):151–158.
  6. 6. Lippold C, van den Bos L, Hohoff A, Danesh G, Ehmer U. Interdisciplinary study of orthopedic and orthodontic findings in pre-school infants [in English, German]. J Orofac Orthop. 2003; 64(5):330–340. doi: 10.1007/s00056-003-0236-4 [CrossRef]
  7. 7. Hedequist D, Emans J. Congenital scoliosis: a review and update. J Pediatr Orthop. 2007; 27(1):106–116. doi: 10.1097/BPO.0b013e31802b4993 [CrossRef]
  8. 8. McMaster MJ, Ohtsuka K. The natural history of congenital scoliosis. A study of two hundred and fifty-one patients. J Bone Joint Surg Am. 1982; 64(8):1128–1147.
  9. 9. Kuklo TR, Lenke LG, Graham EJ, et al. Correlation of radiographic, clinical, and patient assessment of shoulder balance following fusion versus nonfusion of the proximal thoracic curve in adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 2002; 27(18):2013–2020. doi: 10.1097/00007632-200209150-00009 [CrossRef]
  10. 10. Kuklo TR, Lenke LG, Won DS, et al. Spontaneous proximal thoracic curve correction after isolated fusion of the main thoracic curve in adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 2001; 26(18):1966–1975. doi: 10.1097/00007632-200109150-00006 [CrossRef]
  11. 11. Suk SI, Kim WJ, Lee CS, et al. Indications of proximal thoracic curve fusion in thoracic adolescent idiopathic scoliosis: recognition and treatment of double thoracic curve pattern in adolescent idiopathic scoliosis treated with segmental instrumentation. Spine (Phila Pa 1976). 2000; 25(18):2342–2349. doi: 10.1097/00007632-200009150-00012 [CrossRef]
  12. 12. Asher MA, Lai SM, Glattes RC, Burton DC, Alanay A, Bago J. Refinement of the SRS-22 Health-Related Quality of Life questionnaire Function domain. Spine (Phila Pa 1976). 2006; 31(5):593–597. doi: 10.1097/01.brs.0000201331.50597.ea [CrossRef]
  13. 13. Huggare J. Natural head position recording on frontal skull radiographs. Acta Odontol Scand. 1989; 47(2):105–109. doi: 10.3109/00016358909167310 [CrossRef]
  14. 14. Grummons DC, Kappeyne van de Coppello MA. A frontal asymmetry analysis. J Clin Orthop. 1987; 21(7):448–465.
  15. 15. Hwang HS, Youn IS, Lee KH, Lim HJ. Classification of facial asymmetry by cluster analysis. Am J Orthod Dentofacial Orthop. 2007; 132(3):279.e1–6. doi: 10.1016/j.ajodo.2007.01.017 [CrossRef]
  16. 16. Bagó J, Carrera L, March B, Villanueva C. Four radiological measures to estimate shoulder balance in scoliosis. J Pediatr Orthop B. 1996; 5(1):31–34. doi: 10.1097/01202412-199605010-00006 [CrossRef]
  17. 17. Mohanty S, Kumar N. Patterns of presentation of congenital scoliosis. J Orthop Surg (Hong Kong). 2000; 8(2):33–37.
  18. 18. Akel I, Pekmezci M, Hayran M, et al. Evaluation of shoulder balance in the normal adolescent population and its correlation with radiological parameters [published online ahead of print November 20, 2007]. Eur Spine J. 2008; 17(3):348–354. doi: 10.1007/s00586-007-0546-0 [CrossRef]
  19. 19. Qiu XS, Ma WW, Li WG, et al. Discrepancy between radiographic shoulder balance and cosmetic shoulder balance in adolescent idiopathic scoliosis patients with double thoracic curve [published online ahead of print November 29, 2008]. Eur Spine J. 2009; 18(1):45–51. doi: 10.1007/s00586-008-0833-4 [CrossRef]
  20. 20. Peck S, Peck L, Kataja M. Skeletal asymmetry in esthetically pleasing faces. Angle Orthod. 1991; 61(1):43–48.
  21. 21. Pirttiniemi P, Miettinen J, Kantomaa T. Combined effects of errors in frontal-view asymmetry diagnosis. Eur J Orthod. 1996; 18(6):629–636. doi: 10.1093/ejo/18.1.629 [CrossRef]
  22. 22. Zepa I, Huggare J. Reference structures for assessment of frontal head posture. Eur J Orthod. 1998; 20(6):694–699. doi: 10.1093/ejo/20.6.694 [CrossRef]
  23. 23. Zepa I, Hurmerinta K, Kovero O, Nissinen M, Könönen M, Huggare J. Trunk asymmetry and facial symmetry in young adults. Acta Odontol Scand. 2003; 61(3):149–153. doi: 10.1080/00016350310001695 [CrossRef]
  24. 24. Goldberg CJ, Fogarty EE, Moore DP, Dowling FE. Scoliosis and developmental theory: adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 1997; 22(19):2228–2237. doi: 10.1097/00007632-199710010-00006 [CrossRef]
  25. 25. Goldberg CJ, Dowling FE, Fogarty EE, Moore DP. Adolescent idiopathic scoliosis and cerebral asymmetry. An examination of a nonspinal perceptual system. Spine (Phila Pa 1976). 1995; 20(15):1685–1691. doi: 10.1097/00007632-199508000-00007 [CrossRef]
  26. 26. Goldberg CJ, Dowling FE, Fogarty EE, Moore DP. Adolescent idiopathic scoliosis as developmental instability. Genetica. 1995; 96(3):247–255. doi: 10.1007/BF01439579 [CrossRef]
  27. 27. Goldberg CJ, Moore DP, Fogarty EE, Dowling FE. The relationship between minor asymmetry and early idiopathic scoliosis. Stud Health Technol Inform. 2002; (88):17–19.

Mean Value of Facial Parameters

Group Maxilla Height Difference, mm Ramus Length Difference, mm Anterior Nasal Spine-Menton Angle, deg a
Mild 1.17±0.91 2.28±1.64 1.19±0.86
Moderate 1.16±0.76 2.31±1.74 1.42±0.97
Severe 1.67±1.06 2.47±2.14 2.95±1.77 b
Control 1.16±0.84 1.77±1.11 1.44±1.31

Mean Value of Shoulder Parameters

Group Coracoid Height Difference, mm Clavicular Angle, deg Clavicle-Rib Intersection Difference, mm a Radiologic Shoulder Height, mm
Mild 6.81±5.61 1.47±1.40 4.93±4.40 8.79±7.23
Moderate 6.33±6.09 1.34±1.27 4.05±3.54 6.86±6.37
Severe 9.56±7.67 1.87±1.78 11.86±3.68 b 9.19±7.18
Control 7.91±6.62 1.70±1.65 4.00±3.05 8.86±7.19

Correlation of Cobb Angle and Parameters

Cobb Angle Correlation
r Value P Value
Maxilla height difference 0.181 .136
Ramus length difference 0.027 .828
Anterior nasal spine-menton angle 0.433 .0001 a
Coracoid height difference 0.168 .168
Clavicle-rib intersection difference 0.511 .001 a
Clavicular angle 0.140 .252
Radiologic shoulder height 0.046 .707

Mean Value of Facial Parameters According to Curve Type

Group Maxilla Height Difference, mm Ramus Length Difference, mm Anterior Nasal Spine-Menton Angle, deg a
Double thoracic 1.54±0.84 2.98±1.82 3.31±1.50 b
Thoracic main 1.38±1.05 1.91±1.56 1.35±1.20
Thoracolumbar/lumbar main 1.10±0.77 2.50±2.11 1.46±1.23
Control 1.16±0.84 1.77±1.11 1.44±1.31

Mean Value of Shoulder Parameters According to Curve Type

Group Coracoid Height Difference, mm Clavicular Angle, deg Clavicle-Rib Intersection Difference, mm a Radiologic Shoulder Height, mm
Double thoracic 9.47±5.66 2.00±1.20 15.78±6.16 b 10.37±6.03
Thoracic main 6.17±5.98 1.27±1.23 3.51±3.45 6.99±6.28
Thoracolumbar/lumbar main 8.00±7.33 1.60±1.45 4.70±3.61 8.13±8.12
Control 7.91±6.62 1.70±1.65 4.00±3.05 8.86±7.19

Correlation Between Facial and Shoulder Parameters

r Value
Maxilla Height Difference Ramus Length Difference Anterior Nasal Spine-Menton Angle
Coracoid height difference 0.470 0.327 a 0.177
Clavicular angle -0.054 0.247 a 0.395 a
Clavicle-rib intersection difference -0.065 0.197 0.647 a
Radiologic shoulder height 0.053 0.258 a 0.166

10.3928/01477447-20110427-14

Sign up to receive

Journal E-contents