Central JSM Neurosurgery and Spine

Cite this article: Gotfryd A, Avanzi O (2018) Current Methods for the Evaluation of Shoulder Balance in Idiopathic Adolescent Scoliosis: A Literature Review. JSM Neurosurg Spine 6(1): 1096.

*Corresponding authorAlberto Gotfryd, Department of Orthopedics and Traumatology, Santa Casa de Misericórdia de São Paulo, Einstein Perdizes Unit, Rua Apiacás, 85 - 3 floor, São Paulo, Brazil

Submitted: 06 February 2018

Accepted: 20 March 2018

Published: 22 March 2018

Copyright© 2018 Gotfryd et al.

OPEN ACCESS

Keywords• Scoliosis; Shoulder; Treatment; Review of the literature

Review Article

Current Methods for the Evaluation of Shoulder Balance in Idiopathic Adolescent Scoliosis: A Literature ReviewAlberto Gotfryd* and Avanzi ODepartment of Orthopedics and Traumatology, Santa Casa de Misericórdia de São Paulo, Brazil

Abstract

Shoulder’s asymmetry is one of the most notable clinical manifestations in individuals with Adolescent Idiopathic Scoliosis (AIS). Several papers have reported a correlation between shoulders unbalance and patients’ dissatisfaction. Despite the availability of several clinical and radiographic methods for the evaluation of the shoulders leveling in the current literature, there are still many controversies about how to do it properly. Moreover, the correlation between cosmetic deformity and x-rays images is also questionable and surgeons may be giving excessive attention to radiographic images in detriment to the clinical deformity. The present study aims to highlight the most recent methods for the clinical and radiographic measurements of the shoulder balance, as well as the advantages and limitations of each of them.

INTRODUCTIONThe asymmetry of the shoulders is one of the most notable

clinical manifestations in individuals with AIS [1], and the misalignment of the shoulders after surgical treatment worsens results in quality of life scores and generates patient dissatisfaction [2-4]. Thus, it is part of the routine of the orthopedic physical examination an adequate evaluation of thorax asymmetries and measurement of shoulders leveling, by clinical and radiographic methods, which must be repeated at different stages of the treatment [1].

There is no consensus in the medical literature about the best method of evaluating of shoulder misalignment. Several clinical and radiographic measurements are described. There are also radiographic measurements of the thorax and the ribs that can complement the analysis. More recently, software’s have been employed for this purpose. The present study aims to highlight the most recent methods available in the current literature for the clinical and radiographic measurement of shoulder unbalance, as well as the advantages and limitations of each of them.

CLINICAL MEASUREMENTSClinical evaluation should be considered the most important

reference, because it is the one that is visible to the patient. It can be performed ventrally or dorsally (Figure 1), but the correlation between these two evaluations is questionable [6].

Biacromial angle

Should be drawn in a clinically photography in posterior view. It is the angle formed between the line that touches both

Acromion and the horizontal plane (Figure 2). The value obtained must be expressed in degrees. In medical literature, there is not a threshold value for the definition of “shoulder decompensation” [6].

External angle of the shoulder

Analogous to the biacromial angle, it is the angular measurement obtained between a straight line that touches the highest points of both Acromion and the horizontal plane (Figure 3a) [5].

Anterior axillary angle

Is the angle formed from a line that touches both axillary

Figure 1 Ventral and dorsal clinical evaluation of the leveling of the shoulders. It is possible to observe the right shoulder elevation, measured by means of the biacromial angle, is twice as high when evaluated ventrally.

Central

Gotfryd et al. (2018)Email:

JSM Neurosurg Spine 6(1): 1096 (2018) 2/4

fold and the horizontal plane, with the patient being observed ventrally (Figure 3b) [5].

Posterior axillary angle

Is the angle formed from the line that touches both axillary fold and the horizontal plane, with the patient being observed dorsally (Figure 3c) [5].

The trapezial prominence: Should be drawn in a clinically photography in anterior view. Represents the angle between the horizontal line and the line connecting the intersections of sternocleidom astoid muscle and trapezius muscle profiles, with a positive value assigned when the left side was higher than the right. The trapezial area was defined as the area enclosed by the following borders: the line connecting the top margin of acromial processes, the perpendicular line to it through the intersection of sternocleidomastoid muscle and trapezius muscle, and the superior margin of the trapezial muscle.

Radiographic measurements

Clavicle angle: Measured in posteroanterior spine x-rays, it is the intersection of a line drawn between the highest points of the clavicles and the horizontal plane (Figure 4). Positive values are usually used to describe a left shoulder elevation and negative values for the opposite. However, there is no standardization for these measurements and the reverse can be also observed in the literature [7].

Chest cage angle difference: this tool can be used to identify the presence of superior chest cage asymmetries [8]. It is measured as following: 1.a “central chest cage thoracic line” (CCCL) is drawn from the center of T1 to the center of T12; 2. A line is drawn perpendicular to the first line; 3. After that, two lines that touch the clavicles bilaterally are identified; 4. The angle formed by the intersection of the CCCL and the vertical line is the “chest cage clavicle angle” (CCCA).5. The difference of the CCCA is calculated by means of the subtraction of the right and left angles (Figure 5). Such results determine the following classification: < 0 degrees, minimal deformity; 0 to 10 degrees, mild deformity; >10 severe, severe deformities.

T1 tilt: It is the angle formed by a straight line that touches the upper plateau of T1 and the horizontal plane [9].

First Rib Index: It is the difference between the diameter of the first vertebral arch on the right and left side divided by the diameter of the thorax at the same level. The value is expressed as a percentage [10].

Coracoid height: It is the distance, expressed in millimeters, between two horizontal lines, traced from the right and left coracoid processes in a posteroanterior x-ray. Due to the risk of distortions resulting from the magnification or minimization of the x-ray, calibration of the images must be carried out before measurements [10].

SOFTWARE’SSAPO

Software for Postural Evaluation is free software that can be used to measure position, length, angles and the alignment of the body. It requires clinical images of the entire body in the

anterior, posterior, right and left lateral views, marked with pre-established anatomical landmarks (Figure 7) [11].

Surgimap

Computer program developed for the measurement of several radiographic or clinical parameters in patient photographs and x-rays. It can be accessed, free of charge, through the website <http://www.surgimap.com>.

DISCUSSIONShoulders’ leveling is a primary goal of the surgical treatment

of AIS patients [12-16]. When absent, in addition to being related to worse indicators of quality of life [2], unevenness causes patient dissatisfaction. Thus, shoulder measurement has gained importance in recent years, and several methods have been described for this purpose.

Figure 2 Measurement of the clinical deformity of shoulders by means of the biacromial angle - in which a straight line that touches both Acromion - and its relationship with the horizontal plane should be drawn.

Figure 3 Clinical photographs of a patient in ventral view - left image, in which the external shoulder angle (measurement “a”) and the anterior axillary angle (measurement “b”) - and dorsal view - the right image in which measures the posterior axillary angle (measurement “c”).

Figure 4 Illustration of the clavicle angle. The angle is comprised between a line that touches the highest points of the clavicles bilaterally and the horizontal plane. The left side is represented by “L” and the right by “R”.

Central

Gotfryd et al. (2018)Email:

JSM Neurosurg Spine 6(1): 1096 (2018) 3/4

Although most physicians evaluate patients looking at them from the back, the ventral deformity is the one seen by the individual when observed in the mirror [5]. Yang et al. [6], reported that patients with double thoracic deformities (Lenke 2 curves), only had ventral deformities correlated with radiographic changes. In addition, the correlation between ventral and dorsal clinical measurements of the shoulders was weak.

Several studies have attempted to correlate clinical and radiographic shoulder deformities [2,3,5,6,9,10,13]. Qiu et al. [12], evaluated 34 patients with Lenke 2 curves and observed that such correlation occurred only partially. The authors stated that the aesthetic balance was more important than the radiographic one, and that both did not always walk together.

Hong et al. [10], studied four radiographic methods for measuring shoulder height and found that the clavicular angle and difference height of the coracoids were the most reliable. The clavicular angle was also pointed out by other authors as having the best predictive factor for the postoperative balance of the shoulders [4]. According to Kuklo et al. [2], the leveling of the shoulders was also correlated with better quality of life scores. Residual elevation of two or more centimeters of the shoulder was a potential cause of dissatisfaction in patients submitted to spinal fusion [18].

Ono et al. [19], examined two clinical parameters of the shoulders: the clavicular tilt (biacromial angle) and the trapezius prominence in AIS patients with Lenke 1 and 2 type curves. According to them, there are two distinct deformities: the medial asymmetries of the trapezius muscle, which reflect the deformities created by inclined ribs and T1, and the lateral differences, which are related to changes on the clavicular angle.

Regarding T1 tilt, Menon et al. [16], studied 85 AIS cases (Lenke 1 and 2) and observed that the shoulder height may or may not correlate with the T1 slope. In addition, the deformity may depend on the magnitude of both the proximal and main thoracic curves. However, in a retrospective study, Lee et al. [19], reported that T1 tilt had no correlation with the shoulder asymmetry.

Currently, shoulder height has been subject of several publications for the indication of fusion level [20-25] and the density of pedicle screws constructions [26,27]. In addition, the development of more powerful surgical implants led to the creation of iatrogenic deformities, especially at the non-instrumented lumbar curves as well as at the shoulders [28-30]. Such arguments have stimulated the development of more accurate shoulder height measurement tools that should be easy to apply and have good reproducibility among observers.

FINAL CONSIDERATIONSCurrently, there are several clinical and radiographic

methods for evaluating shoulder height, both in the ventral and in the dorsal view. There is no clear superiority between methods, although the clavicular angle presents the best clinical radiographic correlation. In Lenke type 2 curves, the measurement of the ventral deformity of the shoulders seems to be more reliable than the dorsal one.

REFERENCES1. Moe JH, Byrd JA. Idiopathic Scoliosis. In: Moe’s Scoliosis and other

spinal deformities. Translations of Terezinha Oppido. 1994; 191-232.

2. Kuklo TR, Lenke LG, Graham EJ, Won DS, Sweet FA, Blanke KM, 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: 2013-2020.

Figure 5 Posteroanterior x-ray of the spine with a drawing of the angle formed by the clavicles and the left (CCT E) and right (CCT D) thoracic chests, drawn from the chest wall (LCC), its perpendicular and the lines tangent to the right and left clavicles. The angle formed between the latter and the perpendicular is called the clavicle-rib cage angle.

Figure 6 Schematic drawing of the of the first rib index, calculated by the difference of the diameter of the first right (A) and left (B) vertebral arch, divided by the diameter of the thoracic.

Figure 7 Use of SAPO software to evaluate an AIS patient. The white dots are previously established and should be used as a parameter for the analysis of several angles in anterior, posterior and lateral views (image displayed with authors’ permission).

Central

Gotfryd et al. (2018)Email:

JSM Neurosurg Spine 6(1): 1096 (2018) 4/4

Gotfryd A, Avanzi O (2018) Current Methods for the Evaluation of Shoulder Balance in Idiopathic Adolescent Scoliosis: A Literature Review. JSM Neurosurg Spine 6(1): 1096.

Cite this article

3. Asher MA, Burton DC. Adolescent idiopathic scoliosis: natural history and long term treatment effects. Scoliosis. 2006; 1: 2.

4. Raso VJ, Lou E, Hill DL, Mahood JK, Moreau MJ, Durdle NG. Trunk distortion in adolescent idiopathic scoliosis. J Pediatr Orthop. 1998; 18: 222-226.

5. Yang S, Feuchtbaum E, Werner BC, Cho W, Reddi V, Arlet V. Does anterior shoulder balance in adolescent idiopathic scoliosis correlate with posterior shoulder balance clinically and radiographically? Eur Spine J. 2012; 21: 1978-1983.

6. Yang S, Jones-Quaidoo SM, Eager M, Griffin JW, Reddi V, Novicoff W, et al. Right adolescent idiopathic thoracic curve (Lenke 1 A and B): does cost of instrumentation and implant density improve radiographic and cosmetic parameters? Eur Spine J. 2011; 20: 1039-1047.

7. Ginsburg H, Goldstein L, De Vanny J. An evaluation of the upper thoracic curve in idiopathic scoliosis: Guidelines in the selection of the fusion area. Paper presented at: Annual Meeting of the Scoliosis Research Society. 1977.

8. Yagi M, Takemitsu M, Machida M. Chest cage angle difference and rotation of main thoracic curve are independent risk factors of postoperative shoulder imbalance in surgically treated patients with adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 2013; 38: 1209-1215.

9. Bagó J, Carrera L, March B, Villanueva C. Four radiological measures to estimate shoulder balance in scoliosis. J Pediatr Orthop B. 1996; 5: 31-34.

10. Hong JY, Suh SW, Yang, SY Park, Han JH. Reliability analysis of shoulder balance measures comparison of the 4 available methods. Spine (Phila Pa 1976). 2013; 38: 1684-1690.

11. Santos LM, Souza TP, Crescentini MCV, Poleeto PR, Gotfryd AO, Chiau Yi, L. Postural evaluation by photogrammetry in patients with idiopathic scoliosis submitted to arthrodesis: a pilot study. Fisioter Mov. 2012; 25: 165-173.

12. Qiu XS, Ma WW, Li WG, Wang B, Yu Y, Zhu ZZ, et al. How to determine the upper level of instrumentation in Lenke types 1 and 2 adolescent idiopathic scoliosis patients. Eur Spine J 2009; 18: 45-51.

13. Carlson BB, Burton DC, Asher MA. Comparison of trunk and spine deformity in adolescent idiopathic scoliosis. Scoliosis. 2013; 8: 2.

14. Suk SI, Kim WJ, Lee CS, Lee SM, Kim JH, Chung ER, 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: 2342-2349.

15. Chang DG, Ha KY, Kim JH, Kim SS, Lim DJ, Suk SI. How to improve shoulder balance in the surgical correction of double thoracic adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 2014; 39: 1359-1367.

16. Menon KV, Tahasildar N, Pillay HM, Anbuselvam M, Renjit KJ. Patterns of shoulder imbalance in adolescent idiopathic scoliosis: a retrospective observational study. J Spinal Disord Tech. 2014; 27: 401-408.

17. Timothy R. Kuklo, M, Lenke LG. Correlation of Radiographic, Clinical, and Patient Assessment of Shoulder Balance Following Fusion Versus Nonfusion of the Proximal Thoracic Curve in Adolescent Idiopathic Scoliosis. Spine. 2002; 27: 2013-2020.

18. Smyris PN, Sekouris N. Surgical assessment of the proximal thoracic curve in adolescent idiopathic scoliosis. Eur Spine J. 2009; 18: 522-530.

19. Ono T, Bastrom TP, Newton PO. Defining 2 components of shoulder imbalance: clavicle tilt and trapezial prominence. Spine (Phila Pa 1976). 2012; 37: 1511-1516.

20. Lee CK, Denis F, Winter RB. Analysis of the upper thoracic curve in surgically treated idiopathic scoliosis. A new concept of the double thoracic curve pattern. Spine (Phila Pa 1976). 1993; 18: 1599-1608.

21. Sanders AE, Baumann R, Brown H, Johnston CE, Lenke LG, Sink E. Selective anterior fusion of thoracolumbar/lumbar curves in adolescents: when can the associated thoracic curve be left unfused? Spine (Phila Pa 1976). 2003; 28: 706-713.

22. Cao K, Watanabe K, Hosogane N, Toyama Y, Yonezawa I, Machida M, et al. Association of postoperative shoulder balance with adding-on in Lenke Type II adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 2014; 39: 705-712.

23. Winter RB. The idiopathic double thoracic curve pattern. Its recognition and surgical management. Spine (Phila Pa 1976). 1989; 14: 1287-1292.

24. Elfiky TA, Samartzis D, Cheung WY, Wong YW, Luk KD, Cheung KM. The proximal thoracic curve in adolescent idiopathic scoliosis: surgical strategy and management outcomes. Global Spine J. 2011; 1: 27-36.

25. Cil A, Pekmezci M, Yazici M, Alanay M, Acaroglu ME, Deviren V, et al. The Validity of Lenke Criteria for Defining Structural Proximal Thoracic Curves in Patients with Adolescent Idiopathic Scoliosis. Spine. 2005; 30: 2550-2555.

26. Gotfryd AO, Avanzi O. Randomized clinical study on surgical techniques with different pedicle screw densities in the treatment of adolescent idiopathic scoliosis types Lenke 1A and 1B. Spine Deformity. 2013; 1: 272-279.

27. Yang S, Jones-Quaidoo SM, Eager M, Griffin JW, Reddi V, Novicoff W, et al. Right adolescent idiopathic adolescent curve (Lenke 1A and 1B): does cost instrumentation and implant density improve radiographic and cosmetic parameters? Eur Spine J. 2011; 20: 1039-1047.

28. Imrie M, Yaszay B, Bastrom TP, Wenger DR, Newton PO. Adolescent idiopathic scoliosis: should 100% correction be the goal? J Pediatr Orthop. 2011; 31: 9-13.

29. Sanders JO, Diab M, Richards SB. Fixation points within the main thoracic curve: does more instrumentation produce greater curve correction and improved results? Spine (Phila Pa 1976). 2011; 36: 1402.

30. Carreon LY, Sanders JO, Diab M, Sturm PF, Sucato DJ. Patient satisfaction after surgical correction of adolescent idiopathic scoliosis. Spine (Phila Pa 1976). 2011; 36: 965-968.