SPINE Volume 40, Number 1, pp 50-55 ©2014, Lippincott Williams & Wilkins
OUTCOMES
Outcomes of Bracing in Juvenile Idiopathic Scoliosis Until Skeletal Maturity or Surgery Amir Khoshbin, MD,* Liora Caspi, MSc,† Peggy W. Law, MSc,† Sandra Donaldson, BA,‡ Derek Stephens, MSc,† Trevor da Silva, BSc,§ Catharine S. Bradley, MSc,¶ and James G. Wright, MD, MPH, FRCSC*
Study Design. Retrospective comparative study. Objective. To evaluate the outcome of bracing in patients with juvenile idiopathic scoliosis (JIS) at either skeletal maturity or time of scoliosis surgery. Summary of Background Data. JIS is generally thought to have poor outcomes with high rates of surgical fusion. Methods. All patients with JIS between the ages of 4 and 10 years treated with a brace at the Hospital for Sick Children (SickKids) between 1989 and 2011 were eligible. Data were collected from patient health records until either 2 years after skeletal maturity or date of surgery. Results. The average age at diagnosis of 88 patients with JIS was 8.4 ± 1.4 years, with a female to male ratio of approximately 8:1. Pretreatment, Risser score was zero for 80 patients (91%); 72 (92%) of the females were premenarche; and primary Cobb angles ranged from 20° to 71°. Of the 88 patients, 60 (68%) had used a thoracolumbosacral orthosis exclusively; 28 (32%) patients used “other braces” (Milwaukee, Charleston, or a combination of braces), with an average treatment duration of 3.6 ± 1.9 years. As per Scoliosis Research Society definitions, a “non–curveprogression” (≤5° change) group consisted of 25 (28%) patients; and a “curve-progression” group consisted of 63 (72%) patients where the curve had progressed 6° or more. Of the 88 patients, 44 (50%) underwent surgery. The operative rate was higher for patients with curves 30° or more than those
From the *Faculty of Orthopaedic Surgery, University of Toronto; †Child Health Evaluative Sciences; ‡Developmental and Stem Cell Biology Program; §Centre for Orthotics and Medical Devices; ¶Department of Rehabilitation Services; and Department of Surgery, The Hospital for Sick Children, Toronto, Ontario, Canada. Acknowledgment date: March 12, 2013. First revision date: October 17, 2013. Second revision date: August 6, 2014. Acceptance date: September 1, 2014. The device(s)/drug(s) is/are FDA-approved or approved by corresponding national agency for this indication. SickKids Foundation funds were received in support of this work. Relevant financial activities outside the submitted work: board membership, employment, grants. Address correspondence and reprint requests to Amir Khoshbin, MD, Faculty of Orthopaedic Surgery, University of Toronto, The Hospital for Sick Children, S107-555 University Ave, Toronto, Ontario, Canada M5G 1×8; E-mail: [email protected] DOI: 10.1097/BRS.0000000000000669
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with curves 20° to 29° prior to brace treatment (37/58 [64%] vs. 7/30 [23%], respectively; P = 0.001); other braces compared with thoracolumbosacral orthosis (19/28 [68%] vs. 25/60 [42%], respectively; P = 0.02); Lenke I and III curves compared with Lenke VI curves (33/54 [61%] vs. 2/14 [14%], respectively; P = 0.007). Key words: juvenile idiopathic scoliosis, bracing, curve progression, operative, skeletal maturity. Level of Evidence: 3 Spine 2015;40:50–55
I
diopathic scoliosis has been categorized into 3 age groups: infantile idiopathic scoliosis, juvenile idiopathic scoliosis (JIS), and adolescent idiopathic scoliosis (AIS). JIS, defined as scoliosis occurring between the ages of 3 years1–6 or 4 years1,7–10 and 10 years, represents approximately 8% to 24% of idiopathic cases.5,11 It is more common in females, particularly in patients between the ages of 7 and 9 years, with an estimated female to male ratio of 2:1 to 4:1.2,7–9 The longer growth period presumably places patients with JIS at a higher risk for curve progression and subsequent surgery. Though many curves seem to stabilize initially with treatment, rapid increase is frequently noted during the peak growth velocity.5,7,11,12 Reports on the success of bracing in this population range between 13% and 81%.2,4,5,7,10 This variability is not unexpected given the inconsistent definition of success used in previous studies. Despite ongoing research efforts, factors that influence bracing outcome in patients with JIS remain unclear. The purpose of this study was to follow a cohort of patients, all treated by bracing, until either 2 years after skeletal maturity or spinal arthrodesis.
MATERIALS AND METHODS Study Population Ethics board approval was obtained from the Hospital for Sick Children prior to commencement. The guidelines recommended by the Scoliosis Research Society were considered when designing this study.13 A total of 734 patients with scoliosis were treated at the Hospital for Sick Children in Toronto, Ontario, Canada, between January 1, 1982 and December 31, 2011. Patients diagnosed with JIS, defined as scoliosis occurring between 4 and 10 years inclusive, with no January 2015
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPINE130325_LR 50
26/11/14 6:13 AM
OUTCOMES prior operative treatments were included. All nonidiopathic cases were excluded. A cohort of 88 patients with JIS was identified, all of whom were treated initially by bracing. All females began treatment either premenarche or within 1 year of menarche.
Bracing Treatment
Outcomes Bracing JIS • Khoshbin et al
in-brace correction. Finally, we contacted all patients in the nonoperative group to determine if they had surgery at an adult institution.
Statistical Analysis Statistical analyses were performed using SAS software version 9.1 (SAS Institute, Cary, NC), with α values preset at 0.05. Data were evaluated using independent samples t tests for continuous data and the χ2 or Fisher exact test (when appropriate) for categorical data. We compared the characteristics of patients in (1) operative versus nonoperative groups, and (2) progression versus no progression groups. We also examined the effects of brace type, baseline curve magnitude and classification, and in-brace correction on overall curve progression.
Three types of braces were prescribed by physicians during the study period on the basis of physician choice or for some patients, if offered, if they chose the Charleston brace: (1) the thoracolumbosacral orthosis (TLSO), (2) the Milwaukee, and (3) the Charleston. All 3 were readily available to our cohort, with minimal differences in materials and construction techniques over time at the Hospital for Sick Children. Patients were recommended to wear the TLSO and Milwaukee brace full time (22–23 hr/d), and the Charleston brace at night only. Compliance, as reported by patients, was recorded at subsequent clinic visits and stratified as: (1) full (brace wear ≥20 hr/d or entire night for Charleston), (2) partial (
OUTCOMES
Outcomes of Bracing in Juvenile Idiopathic Scoliosis Until Skeletal Maturity or Surgery Amir Khoshbin, MD,* Liora Caspi, MSc,† Peggy W. Law, MSc,† Sandra Donaldson, BA,‡ Derek Stephens, MSc,† Trevor da Silva, BSc,§ Catharine S. Bradley, MSc,¶ and James G. Wright, MD, MPH, FRCSC*
Study Design. Retrospective comparative study. Objective. To evaluate the outcome of bracing in patients with juvenile idiopathic scoliosis (JIS) at either skeletal maturity or time of scoliosis surgery. Summary of Background Data. JIS is generally thought to have poor outcomes with high rates of surgical fusion. Methods. All patients with JIS between the ages of 4 and 10 years treated with a brace at the Hospital for Sick Children (SickKids) between 1989 and 2011 were eligible. Data were collected from patient health records until either 2 years after skeletal maturity or date of surgery. Results. The average age at diagnosis of 88 patients with JIS was 8.4 ± 1.4 years, with a female to male ratio of approximately 8:1. Pretreatment, Risser score was zero for 80 patients (91%); 72 (92%) of the females were premenarche; and primary Cobb angles ranged from 20° to 71°. Of the 88 patients, 60 (68%) had used a thoracolumbosacral orthosis exclusively; 28 (32%) patients used “other braces” (Milwaukee, Charleston, or a combination of braces), with an average treatment duration of 3.6 ± 1.9 years. As per Scoliosis Research Society definitions, a “non–curveprogression” (≤5° change) group consisted of 25 (28%) patients; and a “curve-progression” group consisted of 63 (72%) patients where the curve had progressed 6° or more. Of the 88 patients, 44 (50%) underwent surgery. The operative rate was higher for patients with curves 30° or more than those
From the *Faculty of Orthopaedic Surgery, University of Toronto; †Child Health Evaluative Sciences; ‡Developmental and Stem Cell Biology Program; §Centre for Orthotics and Medical Devices; ¶Department of Rehabilitation Services; and Department of Surgery, The Hospital for Sick Children, Toronto, Ontario, Canada. Acknowledgment date: March 12, 2013. First revision date: October 17, 2013. Second revision date: August 6, 2014. Acceptance date: September 1, 2014. The device(s)/drug(s) is/are FDA-approved or approved by corresponding national agency for this indication. SickKids Foundation funds were received in support of this work. Relevant financial activities outside the submitted work: board membership, employment, grants. Address correspondence and reprint requests to Amir Khoshbin, MD, Faculty of Orthopaedic Surgery, University of Toronto, The Hospital for Sick Children, S107-555 University Ave, Toronto, Ontario, Canada M5G 1×8; E-mail: [email protected] DOI: 10.1097/BRS.0000000000000669
50
www.spinejournal.com
with curves 20° to 29° prior to brace treatment (37/58 [64%] vs. 7/30 [23%], respectively; P = 0.001); other braces compared with thoracolumbosacral orthosis (19/28 [68%] vs. 25/60 [42%], respectively; P = 0.02); Lenke I and III curves compared with Lenke VI curves (33/54 [61%] vs. 2/14 [14%], respectively; P = 0.007). Key words: juvenile idiopathic scoliosis, bracing, curve progression, operative, skeletal maturity. Level of Evidence: 3 Spine 2015;40:50–55
I
diopathic scoliosis has been categorized into 3 age groups: infantile idiopathic scoliosis, juvenile idiopathic scoliosis (JIS), and adolescent idiopathic scoliosis (AIS). JIS, defined as scoliosis occurring between the ages of 3 years1–6 or 4 years1,7–10 and 10 years, represents approximately 8% to 24% of idiopathic cases.5,11 It is more common in females, particularly in patients between the ages of 7 and 9 years, with an estimated female to male ratio of 2:1 to 4:1.2,7–9 The longer growth period presumably places patients with JIS at a higher risk for curve progression and subsequent surgery. Though many curves seem to stabilize initially with treatment, rapid increase is frequently noted during the peak growth velocity.5,7,11,12 Reports on the success of bracing in this population range between 13% and 81%.2,4,5,7,10 This variability is not unexpected given the inconsistent definition of success used in previous studies. Despite ongoing research efforts, factors that influence bracing outcome in patients with JIS remain unclear. The purpose of this study was to follow a cohort of patients, all treated by bracing, until either 2 years after skeletal maturity or spinal arthrodesis.
MATERIALS AND METHODS Study Population Ethics board approval was obtained from the Hospital for Sick Children prior to commencement. The guidelines recommended by the Scoliosis Research Society were considered when designing this study.13 A total of 734 patients with scoliosis were treated at the Hospital for Sick Children in Toronto, Ontario, Canada, between January 1, 1982 and December 31, 2011. Patients diagnosed with JIS, defined as scoliosis occurring between 4 and 10 years inclusive, with no January 2015
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPINE130325_LR 50
26/11/14 6:13 AM
OUTCOMES prior operative treatments were included. All nonidiopathic cases were excluded. A cohort of 88 patients with JIS was identified, all of whom were treated initially by bracing. All females began treatment either premenarche or within 1 year of menarche.
Bracing Treatment
Outcomes Bracing JIS • Khoshbin et al
in-brace correction. Finally, we contacted all patients in the nonoperative group to determine if they had surgery at an adult institution.
Statistical Analysis Statistical analyses were performed using SAS software version 9.1 (SAS Institute, Cary, NC), with α values preset at 0.05. Data were evaluated using independent samples t tests for continuous data and the χ2 or Fisher exact test (when appropriate) for categorical data. We compared the characteristics of patients in (1) operative versus nonoperative groups, and (2) progression versus no progression groups. We also examined the effects of brace type, baseline curve magnitude and classification, and in-brace correction on overall curve progression.
Three types of braces were prescribed by physicians during the study period on the basis of physician choice or for some patients, if offered, if they chose the Charleston brace: (1) the thoracolumbosacral orthosis (TLSO), (2) the Milwaukee, and (3) the Charleston. All 3 were readily available to our cohort, with minimal differences in materials and construction techniques over time at the Hospital for Sick Children. Patients were recommended to wear the TLSO and Milwaukee brace full time (22–23 hr/d), and the Charleston brace at night only. Compliance, as reported by patients, was recorded at subsequent clinic visits and stratified as: (1) full (brace wear ≥20 hr/d or entire night for Charleston), (2) partial (
