Trends in the Utilization of Implants in Index Procedures for Early Onset Scoliosis From the Pediatric Spine Study Group.

INTRODUCTION: Because of the relative rarity of Early Onset Scoliosis (EOS) cases, patient registries were developed to combine clinical information from multiple institutions to maximize patient care and outcomes. This study examines the history and trends regarding the use of growth-friendly devices for index surgical procedures in EOS patients within the Pediatric Spine Study Group database. METHODS: All index growth-friendly implants were queried from registry inception until October 2020. EOS etiology, device/implant type, and geographic area/institution for each procedure were recorded. RESULTS: From 1994 to 2020, 2786 patients underwent index surgery at a mean age of 6.2±2.9 years. There were 908 traditional growing rods (TGR) (32.3%), 922 vertical expandable prosthetic titanium rib devices (VEPTR) (33.1%), 5 hybrid VEPTR/TGR (0.18%), and 951 magnetically controlled growing rods (MCGR) (34.2%) index implants. Fifty-six different institutions reported an index implant, and 5 accounted for 823 (30%) of the cases during the study period. Institutions in the Northeast accounted for more index implants than other regions of the United States. There was a 40% increase in index implant insertions annually when comparing 1994 (3 implants/1 center) to 2018 (234 implants/56 centers), ( P <0.001). Beginning in 2009, there was a 90.9% decrease in the number of TGR/VEPTR procedures (2009: 156 implants/32 centers; 2019: 22 implants/49 centers P =0.001), and a 479% increase in MCGR (2009: 1 implant/1 center; 2018: 197 implants/34 centers ( P =0.005). The overall number of growth-friendly index procedures performed in 2019 (150/49 centers) decreased 34.5% when compared to 2018 (234/48 centers). CONCLUSION: The number of growth-friendly implants reported in the Pediatric Spine Study Group registry as the initial surgical management of EOS increased markedly over the past 20 years. MCGR is currently the predominant type of device utilized for index surgical procedures by group members, surpassing the use of VEPTR and TGR in 2014. There was a significant decrease in index growth-friendly procedures in 2019 compared to 2018. LEVEL OF EVIDENCE: Level IV.

No Difference in the Rates of Unplanned Return to the Operating Room Between Magnetically Controlled Growing Rods and Traditional Growth Friendly Surgery for Children With Cerebral Palsy.

BACKGROUND: Early-onset scoliosis (EOS) is common in children with cerebral palsy (CP). The effectiveness of magnetically controlled growing rods (MCGR) and the risk for unplanned return to the operating room (UPROR) remain to be studied in this patient population. The primary outcome of this study was to examine the frequency of UPROR between MCGRs as compared with traditional growth friendly (TGF) surgeries for children with EOS secondary to CP. METHODS: Patients with EOS secondary to CP were prospectively identified from an international database, with data retrospectively analyzed. Scoliosis, kyphosis, T1-S1, and T1-T12 height were measured preoperation, immediate postoperation, and at minimum 2-year follow-up. The risk and etiology of UPRORs were compared between MCGR and TGF. RESULTS: Of the 120 patients that met inclusion criteria, 86 received TGF (age 7.5±0. 1.8 y; mean follow-up 7.0±2.9 y) and 34 received MCGR (age 7.1±2.2 y, mean follow-up 2.8±0.0.5 y). Compared with TGF, MCGR resulted in significant improvements in maintenance of scoliosis (P=0.007). At final follow-up, UPRORs were 8 of 34 patients (24%) for MCGR and 37 of 86 patients (43%) for TGF (P=0.05). To minimize the influence of follow-up period, UPRORs within the first 2 years postoperation were evaluated: MCGR (7 of 34 patients, 21%) versus TGF (20 of 86 patients, 23%; P=0.75). Within the first 2 years, etiology of UPROR as a percentage of all patients per group were deep infection (13% TGF, 6% MCGR), implant failure/migration (12% TGF, 9% MCGR), dehiscence (4% TGF, 3% MCGR), and superficial infection (4% TGF, 3% MCGR). The most common etiology of UPROR for TGF was deep infection and for MCGR was implant failure/migration. CONCLUSION: For patients with EOS secondary to CP, there was no difference in the risk of UPROR within the first 2 years postoperatively whether treated with TGF surgery or with MCGRs (23% TGF, 21% MCGR). LEVEL OF EVIDENCE: Level III-retrospective cohort, therapeutic study.

Magnetically Controlled Growing Rods (MCGR) Versus Single Posterior Spinal Fusion (PSF) Versus Vertebral Body Tether (VBT) in Older Early Onset Scoliosis (EOS) Patients: How Do Early Outcomes Compare?

STUDY DESIGN: Retrospective review of prospective data from multicenter registry. OBJECTIVE: Compare outcomes of posterior spinal fusion (PSF) versus magnetically controlled growing rods (MCGR) versus vertebral body tethers (VBT) in 8- to 11-year-old idiopathic early onset scoliosis (EOS) patients. SUMMARY OF BACKGROUND DATA: In EOS, it is unclear at what age the benefit of growth-sparing strategies outweighs increased risks of surgical complications, compared with PSF. METHODS: One hundred thirty idiopathic EOS patients, 81% female, aged 8-11 at index surgery (mean 10.5 yrs), underwent PSF, MCGR, or VBT. Scoliosis curve, kyphosis, thoracic and spinal height, complications, and Quality of Life (QoL) were assessed preoperatively and at most recent follow-up (prior to final fusion for VBT/MCGR). RESULTS: Of 130 patients, 28.5% received VBT, 39.2% MCGR, and 32.3% PSF. The VBT cohort included more females (P < 0.0005), was older (P < 0.0005), more skeletally mature (P < 0.0005), and had smaller major curves (P < 0.0005). At follow-up, scoliosis curve corrected 41.1 ±â€Š22.4% in VBT, 52.2 ±â€Š19.9% in PSF, and 27.4 ±â€Š23.9% in MCGR (P < 0.0005), however, not all VBT/MCGR patients finished treatment. Fifteen complications occurred in 10 VBTs, 6 requiring unplanned surgeries; 45 complications occurred in 31 MCGRs, 11 requiring unplanned surgeries, and 9 complications occurred in 6 PSFs, 3 requiring unplanned revisions. Cox proportional hazards regression adjusted for age, gender, and preoperative scoliosis curve revealed that MCGR (hazard ratio [HR] = 21.0, 95% C.I. 4.8-92.5; P < 0.001) and VBT (HR = 7.1, 95% C.I. 1.4-36.4; P = 0.019) patients were at increased hazard of requiring revision, but only MCGR patients (HR = 5.6, 95% C.I. 1.1-28.4; P = 0.038) were at an increased hazard for unplanned revisions compared with PSF. Thoracic and spinal height increased in all groups. QoL improved in VBT and PSF patients, but not in MCGR patients. CONCLUSION: In older idiopathic EOS patients, MCGR, PSF, and VBT controlled curves effectively and increased spinal height. However, VBT and PSF have a lower hazard for an unplanned revision and improved QoL.Level of Evidence: 3.

The Effect of Proximal Anchor Choice During Distraction-based Surgeries for Patients With Nonidiopathic Early-onset Scoliosis: A Retrospective Multicenter Study.

BACKGROUND: It is unclear whether the type of proximal anchor affects the spine length achieved with distraction-based surgeries in patients with nonidiopathic early-onset scoliosis (EOS). Since distraction may produce kyphosis, spine length should be assessed in the sagittal plane using the sagittal spine length (SSL-curved arc length of the spine in the sagittal plane). Our purpose was to determine if the type of proximal anchor in distraction-based surgeries will affect final spine length. METHODS: Patients with nonidiopathic EOS treated with distraction-based systems (minimum 5 y follow-up, 5 lengthenings) were identified from 2 EOS registries. Radiographic analysis preoperative, postimplant (L1), and after each lengthening (L2-L5, L6-L10, L11-L15) was performed with the primary outcome of T1-S1 SSL. RESULTS: We identified 126 patients-70 had rib-based implants (52 congenital, 9 syndromic, 9 neuromuscular) and 56 had spine-based implants (15 congenital, 29 syndromic, 12 neuromuscular) with preoperative age 4.6 years, scoliosis 75 degrees, and kyphosis 48 degrees. After initial correction (P<0.05), scoliosis remained constant [58 degrees (13 to 104 degrees) at L11-L15] and kyphosis increased over time [38 degrees (9 to 108 degrees) at L1 to 60 degrees (17 to 134 degrees) at L11-L15] (P<0.05). Preoperative SSL was higher in the spine-based group (29.6 cm) when compared with the rib-based group (25.2 cm) (P<0.05). This difference was maintained after initial implantation (spine-based: 32.2 cm vs. rib-based: 26.7 cm, P<0.05) and at final follow-up (spine-based: 37.0 cm vs. rib-based: 34.4 cm, P<0.05). As preoperative SSL differed between groups, maximum SSL gains per interval were also normalized to preoperative SSL. There was no statistically significant difference between groups at L1, L2-L5, and L6-L10. However, at L11-L15, the rib-based group achieved a more relative increase in spine length compared with the spine-based group (45% vs. 31%, P<0.05). CONCLUSION: At minimum 5 year follow-up, distraction-based surgeries increased spine length for patients with nonidiopathic EOS; regardless of proximal anchor type.

Improvement of Pulmonary Function Measured by Patient-reported Outcomes in Patients With Spinal Muscular Atrophy After Growth-friendly Instrumentation.

BACKGROUND: Children with spinal muscular atrophy (SMA) sustain a progressive reduction in pulmonary function (PF) related to both muscular weakness and the concomitant effects of spinal deformity on the thorax. Growth-friendly instrumentation is commonly utilized for younger patients with scoliosis and SMA to halt the progression of spinal curvature, but its effect on PF in these patients has not previously been investigated. Using the change in Early Onset Scoliosis 24-Item Questionnaire (EOSQ-24) PF subdomain scores, the authors will investigate whether PF improves in patients with SMA after a growth-friendly intervention. METHODS: This was a multicenter retrospective cohort study from 2 international registries of patients with SMA undergoing spinal deformity surgery from 2005 to 2015. Data collected were age, sex, degree of major coronal curve, type of growth-friendly construct, forced vital capacity (FVC), and EOSQ-24 scores at the patient's preoperative, 1-year postoperative, and 2-year postoperative visits. Differences in EOSQ-24 PF scores and FVC between baseline and postoperative assessment were examined by paired tests. RESULTS: A total of 74 patients were identified (mean age, 7.6±2.3 y, major curve 68.1±22.4 degrees, 51.4% female individuals). The mean EOSQ-24 PF scores improved significantly from 70.6 preoperatively to 83.6 at 1 year (P=0.092) and 86.5 at 2 years postoperatively (P=0.020). The scores in patients with rib-based constructs showed steeper increases at 1-year assessments than those in patients with spine-based constructs. The mean paired FVC value decreased from 63.9% predicted preoperatively, to 57.6% predicted at 1 year postoperatively (P=0.035), and 61.9% predicted preoperatively, to 56.3% predicted at 2 years postoperatively (P=0.178). CONCLUSIONS: Patients with SMA who received growth-friendly instrumentation did experience improvements in PF as measured by EOSQ-24 assessing the caregivers' perception. Given the uncertain reliability of PFTs in this young population, EOSQ-24 is an important tool for measuring improvements in health-related quality of life. LEVEL OF EVIDENCE: Level III-retrospective study.

Prospectively collected surgeon indications for discontinuation of a lengthening program for early-onset scoliosis.

INTRODUCTION: At some point after children with early-onset scoliosis (EOS) undergo implantation of a distraction construct to control deformity and promote growth, a decision is made to discontinue lengthening. The purpose of this study was to evaluate surgeon indications for discontinuation of a lengthening program and to evaluate patient outcomes. METHODS: As a part of a multicenter database, surgeons prospectively completed a questionnaire at the completion of growth-friendly treatment. Surgeon indications for discontinuation included patient age, pain/functional status, implant status, and spinal deformity parameters. Patient demographics, scoliosis type, deformity parameters, and length of time in a growing program were queried. Patients were treated with a final fusion or observation, and rate of secondary surgeries was analyzed. RESULTS: Questionnaires were completed on 121 patients (61% female). EOS etiology was 31% neuromuscular, 43% congenital, 16% idiopathic, and 10% syndromic. Average age at initiation of growing program was 6.8 ± 3.1 years, and average age at discontinuation was 12.7 ± 2.5 years. The most commonly cited indications for discontinuation of a lengthening program included bone age/skeletal maturity (n = 46), patient age (n = 33), and diminishing returns with expansions (n = 33). A larger coronal Cobb angle was found in patients who underwent definitive fusion (65°) when compared with continued observation (55°, p = 0.001). Twenty-nine (24%) patients were initially treated with observation after completion of a growing construct. In this subgroup, at a minimum of 2 years' (average 3.8 years') follow-up, 26/29 (90%) patients remained stable with observation alone; whereas, three (10%) underwent delayed final fusion surgery. CONCLUSIONS: The most common surgeon-cited indications for discontinuation of a lengthening program in EOS patients are skeletal maturity and patient age. The majority of patients (76%) underwent definitive spinal fusion after discontinuation of a lengthening program; whereas, those treated with observation alone had a survivorship of 90% at a minimum follow-up of two years.

Burden of care in families of patients with early onset scoliosis.

Early onset scoliosis is a complex manifestation of a heterogenous group of disorders, often necessitating multiple medical and surgical interventions to address the spinal deformity and its accompanying comorbidities. Current literature documents decreases in the health-related quality of life of these patients; however, there is a distinct lack of published data examining the burden on their caregivers. The purpose of this study is to compare burden on caregivers of children with early onset scoliosis and those on caregivers of age-matched healthy peers. A multicenter retrospective cohort study was conducted by querying a national registry for patients with early onset scoliosis diagnosed before 10 years old whose caregivers completed the caregiver burden (CB) and financial burden (FB) domains of the Early Onset Scoliosis Questionnaire (EOSQ-24) before their treatment. Scores were compared by etiology and planned treatment. The study identified 503 patients categorized by etiology and eventual treatment type. Overall, FB and CB scores for patients with early onset scoliosis were ≥10% worse than those of their age-matched peers, greater than the minimal clinically important difference for the EOSQ-24 (P < 0.001). Non-idiopathic patients' scores were ≥16% worse than age-matched peers regardless of future treatment (P < 0.001), while scores for idiopathic patients were varied. Idiopathic patients who went on to be observed had similar scores to national norms, but those who were managed either non-operatively (14% worse FB, 7% worse CB; P < 0.001) or operatively (25% worse FB, 27% worse CB; P > 0.05) had caregivers who reported greater burdens compared to those of healthy peers. This study suggests burdens on caregivers of patients with early onset scoliosis of nearly all etiologies are greater than those imposed on caregivers of healthy children, even before the additional stress of treatment is imposed. Level of evidence: II.

Incidence of complications in the management of non-ambulatory neuromuscular early-onset scoliosis with a rib-based growing system: high- versus low-tone patients.

PURPOSE: The purpose of this study is to evaluate whether patients with high-tone neuromuscular early-onset scoliosis have different surgical outcome and complication rate, when compared to patients with low-tone neuromuscular early-onset scoliosis treated with a rib-to-pelvis rib-based dual growing system. METHODS: This is a retrospective cohort study of 67 neuromuscular early-onset scoliosis patients, collected from a multicenter database, treated with a rib-to-pelvis rib-based dual growing system. All patients were divided into two groups: high tone and low tone. Pre-, intra- and postoperative data were compared between both groups. Complications were reported by a standardized system. RESULTS: Twenty-six high-tone and 41 low-tone patients were found homogeneous regarding gender, age at surgery, weight, height, estimated blood loss and surgery time. High-tone group (19/26 = 73.1%) experiences more postoperative complications than low-tone group (22/41 = 53.7%). Most common complications were infection, device migration, death and hardware failure. Permanent abandonment of rib-based growing technique and device removal was required in 21% of high-tone patients (P < 0.001). None of the low-tone patients required abandonment. CONCLUSION: High-tone patients had more complications than those with low tone in management of neuromuscular early-onset scoliosis treated with a rib-to-pelvis rib-based dual growing system. A different surgical approach may be required to treat the high-tone neuromuscular early-onset scoliosis.

Outcomes of Primary and Conversion Magnetically Controlled Growth Rods Are Different at Two-Year Follow-up: Results of North American Release.

STUDY DESIGN: Multicenter retrospective review. OBJECTIVES: To compare the radiographic outcomes and complication rates in patients with primary and conversion magnetically controlled growing rod (MCGR) implants at one and two years after surgery. SUMMARY OF BACKGROUND DATA: Many initial early-onset scoliosis (MCGR) implantations in the United States were conversions from other types of growth-friendly systems, and the outcome similarities and differences between primary and conversion MCGR implantation procedures are still relatively unknown. METHODS: Multicenter retrospective review of EOS patients from two multicenter EOS registries identified consecutive EOS patients treated from 2014 to 2017 with a minimum of one-year follow-up. In addition, a subset of these patients who had two-year follow-up were further analyzed. RESULTS: In total, 383 MCGR patients were identified, of which 272 (71%) were primary (P) and 111 (29%) were conversion (C). Group P patients had significantly greater coronal curves at the time of MCGR implantation and greater initial coronal correction. There was no statistically significant difference in Cobb correction at one year or between follow-up at one and two years. The preimplantation thoracic spine height was identical in both groups, with statistically greater improvement at initial implantation in P than in C patients. Significantly greater height gains were seen in P than in C patients in the one-year follow-up cohort. There was a higher rate of complications in the C group than in the P group; however, the difference was not statistically significant. Overall, most complications were implant-related. No loss of curve correction occurred in either group. CONCLUSIONS: Patients with primary MCGR insertion can be expected to have greater radiographic correction and spine length gain than those with conversion from growth-friendly instrumentation to MCGR, most likely because of increased spine stiffness in conversion patients. The rate of complications, primarily implant-related, remains higher in conversion than in primary insertion patients. LEVEL OF EVIDENCE: Level III.

Distraction-Based Surgeries Increase Spine Length for Patients With Nonidiopathic Early-Onset Scoliosis-5-Year Follow-up.

STUDY DESIGN: Retrospective, comparative. OBJECTIVES: To determine if distraction-based surgeries will increase spine length in patients with nonidiopathic EOS and whether etiology affects final spine length. SUMMARY OF BACKGROUND DATA: As early-onset scoliosis (EOS) has many etiologies, it is unclear whether etiology affects the spine length achieved with distraction-based surgeries. Since distraction may produce kyphosis, sagittal spine length (SSL; curved arc length of the spine in the sagittal plane) should be utilized. METHODS: Patients with nonidiopathic EOS treated with distraction-based systems (minimum 5-year follow-up, 5 lengthenings) were identified from two EOS registries. Radiographic analysis preoperation, postimplant (L1), and after each lengthening (L2-L5, L6-L10, L11-L15) was performed with primary outcome of T1-S1 SSL. RESULTS: We identified 126 patients (67 congenital, 38 syndromic, 21 neuromuscular) with a mean preoperative age of 4.6 years, scoliosis 75°, kyphosis 48°, and a mean of 12 lengthenings. After initial correction (p < .05), scoliosis remained constant (58° at L11-L15) and kyphosis increased (38° at L1 to 60° at L11-L15) (p < .05). SSL increased for the entire group from 27.1 cm preoperation to 35.3 cm at L11-L15 (p < .05) and during the distraction phase (29.2 cm at L1 to 35.3 cm at L11-L15) (p < .05). Preoperative SSL was higher in neuromuscular compared with congenital patients and maintained that difference until the 10th lengthening. Preoperative SSL did not differ between syndromic and congenital patients (28.0 cm vs. 25.6 cm); however, syndromic patients had greater SSL after implantation (L1: 30.5 cm vs. 26.8 cm) (p < .05) and maintained that difference until the 15th lengthening (37.1 cm vs. 34.3 cm) (p < .05). CONCLUSION: At minimum 5-year follow-up, distraction-based surgeries increased spine length for all patients with nonidiopathic EOS; however, neuromusculars had higher preoperative spine length compared with congenital patients and maintained that difference until the 10th lengthening. Although congenital and syndromic patients had similar preoperative spine length, syndromic patients had greater SSL after implantation (L1) and maintained that difference until the 15th lengthening. LEVEL OF EVIDENCE: Level III.

The Effect of Expansion Thoracostomy on Spine Growth in Patients with Spinal Deformity and Fused Ribs Treated with Rib-Based Growing Constructs.

STUDY DESIGN: Retrospective review of prospective registries. OBJECTIVES: We hypothesized that patients with congenitally fused ribs who underwent thoracostomy upon implantation of rib-based distraction devices would achieve improved spine growth compared with those who did not undergo thoracostomy. SUMMARY OF BACKGROUND DATA: Patients with fused ribs may develop thoracic insufficiency syndrome. Treatment for severe early-onset spinal deformity with rib fusions often includes the placement of rib-based expansion devices with surgical division of the fused ribs (thoracostomy). The effect of thoracostomy on spinal growth has not been fully examined. METHODS: Two multicenter registries of primarily prospectively collected data were searched. Patients with fused ribs and implantation of a rib-based device were identified. A total of 151 patients with rib fusions treated with rib-based constructs and minimum two-year follow-up were included. Among those, 103 patients were treated with expansion thoracostomy at the time of implantation, whereas 48 patients received device implantation alone. We evaluated change in T1-T12 and T1-S1 height, coronal Cobb angle, kyphosis, and number of surgeries. Preoperative deformity was similar between the two groups. Only 19% of patient underwent final fusion, with similar numbers fused in each group. RESULTS: At latest follow-up, the expansion thoracostomy group had a greater total improvement in T1-S1 height (7.2 cm vs. 4.8 cm, p = .004). There was no difference between the two groups for change in spinal height at each lengthening procedure. Interestingly, thoracostomy patients also underwent more total surgeries (11.5 vs. 9.6, p = .031) and more lengthening procedures (8.3 vs. 6.6, p = .017) than the comparison group despite similar length of follow-up. CONCLUSIONS: Patients who underwent expansion thoracostomy at the time of rib expansion device implantation achieved greater improvement in T1-S1 height than those who underwent implantation of rib expansion device alone. Further work is needed to evaluate whether expansion thoracostomy impacts pulmonary function.

Best Practice Guidelines for Surgical Site Infection Prevention With Surgical Treatment of Early Onset Scoliosis.

BACKGROUND: Postoperative surgical site infection (SSI) is unfortunately a commonly encountered complication in the surgical treatment of children with Early Onset Scoliosis (EOS). There is documented variation in the treatment of this patient population. Previous work building consensus for the approach to high risk patients (eg, neuromuscular etiology) has been promising. The goal of the current study is to apply similar principles to develop consensus-based guidelines for the treatment of patients with EOS. METHODS: A focus group from 2 multicenter pediatric spine deformity study groups developed a list of statements to be distributed to a larger group of EOS experts. Using the Delphi process, participants were presented with a systematic review of the literature as well as a review of current practices in growth friendly surgery. The first round was conducted using an electronic survey. Results of this survey were then discussed face-to-face and the statements were further refined. A final round was conducted using the Audience Response System, allowing participants to vote for each statement (strongly agree or agree). Agreement >80% or disagreement <20% was considered consensus. RESULTS: A total of 29 of 57 statements reached consensus. Negative statements (statements of disagreement) were excluded, so the final consensus guidelines included 22 statements. The number of statements from the previously published Best Practice Guidelines (BPG) approved for insertion and lengthening growth friendly procedures were 12 of 14 and 11 of 14, respectively. The high risk BPG therefore does not cover all of the issues specific to the EOS population, and explains why 22 statements reached consensus in the current guideline. Upon completion of the surveys, 100% of the participants agreed to support its publication. CONCLUSIONS: Using the Delphi process several "best practices" were developed for growth friendly surgical treatment of EOS. LEVEL OF EVIDENCE: Level V.

Spine Deformity With Fused Ribs Treated With Proximal Rib- Versus Spine-Based Growing Constructs.

STUDY DESIGN: Retrospective review of prospectively collected data. OBJECTIVE: To compare the use of spine-based versus rib-based implants for the treatment of early-onset scoliosis (EOS) in the setting of rib fusions. SUMMARY OF BACKGROUND DATA: Treatment for severe early-onset spinal deformity with rib fusions includes growing spine devices with proximal rib or spine anchors. The results of treatment, however, have not been compared between spine-based versus rib-based proximal anchors. METHODS: 169 patients with rib fusions treated with rib-based or spine-based constructs and minimum two-year follow-up were included. Sixteen patients were treated with proximal spine-based anchors and 153 with proximal rib-based devices (VEPTRs). Overall, 104 of the patients with rib-based fixation underwent thoracoplasty at the index surgery. We evaluated change in T1-T12 and T1-S1 height, coronal Cobb angle, kyphosis, and number of lengthening/revision surgeries. RESULTS: Kyphosis increased a mean of 7° in the rib-based group and decreased a mean of 20 degrees in the spine-based group (p = .002). Major Cobb angle decreased in both groups (p < .0001); however, the spine-based group had greater Cobb angle improvement (24 vs. 11 degrees, p = .04). From implant and lengthening of distraction devices, there was a mean 3.3-cm (22%) increase in T1-T12 height and a mean of 8.0 lengthenings in the rib-based group compared with a 5.7-cm increase and 6.3 lengthening surgeries in the spine-based group. Patients with rib-based constructs had a mean of 11 total procedures, whereas spine-based patients had a mean of 8. CONCLUSIONS: Patients underwent a mean of eight lengthening surgeries before final fusion or cessation of lengthening with a modest 2.3-cm increase in T1-T12 height. Compared with proximal rib anchors, proximal spine anchors controlled kyphosis and improved Cobb angle correction for early-onset scoliosis with rib fusions.

Expert Consensus and Equipoise: Planning a Randomized Controlled Trial of Magnetically Controlled Growing Rods.

STUDY DESIGN: Expert consensus building using combined Delphi method and Nominal group technique. OBJECTIVES: To identify the current state of equipoise surrounding the use of magnetically controlled growing rods (MCGRs) and to determine consensus for planning a randomized controlled trial (RCT) with MCGRs. BACKGROUND: The use of MCGRs for the treatment of early-onset scoliosis (EOS) is a new technology. Optimal use has not been thoroughly investigated and much uncertainty exists. Areas of uncertainty include construct architecture, timing of lengthenings, and amount of distraction per lengthening. Expert discussion and consensus is useful at this early juncture and necessary when designing an RCT. METHODS: Two rounds of surveys were administered to a group of experienced pediatric spine surgeons, followed by a 2-hour, face-to-face meeting in November 2015 and a 1-hour, face-to-face meeting in February 2016. The first survey used example cases to establish agreement around the proper use of MCGRs and identified areas of equipoise and disagreement. The second survey again used example cases-this time selected for their equipoise status-to solicit trial arms for a potential RCT of MCGRs and identified important open questions in the use of MCGRs. Lastly, the face-to-face meetings employed iterative voting to preliminarily plan an RCT of MCGRs. RESULTS: Following the Delphi survey rounds and the two Nominal face-to-face meetings, the group of experts decided on an MCGR RCT design that standardized all patients to bidirectional constructs, and randomized to a lengthening interval of 6 versus 16 weeks with a standardized equation for calculating the total yearly lengthening that approximates normal spine growth. CONCLUSION: This endeavor indicates expert support for the use of MCGR in children older than 6 years, with curves greater than 60°. The uncertainty surrounding frequency of lengthening justifies an RCT of MCGRs. LEVEL OF EVIDENCE: Level V.

Growth-Friendly Surgery Is Effective at Treating Early-Onset Scoliosis Associated With Goldenhar Syndrome.

OBJECTIVE: To evaluate the radiographic results and complications of growth-friendly (GF) surgery in the treatment of early-onset scoliosis (EOS) associated with Goldenhar syndrome. BACKGROUND: Goldenhar syndrome has been associated with spinal deformity, which may be progressive. Efficacy and complication rate of GF treatment has not been reported for this population of patients with EOS. METHODS: Patients with Goldenhar syndrome and EOS with two years' follow-up were identified from two international multicenter EOS databases. Scoliosis, kyphosis, spine height, and hemithoracic height/width were determined preimplant, immediately postoperative, and at the two-year follow-up. Severity of complications (SV) was recorded (Smith et al. JPO 2015). RESULTS: Ten patients met inclusion criteria and had a mean age of 4.6 ± 2.5 years at GF implantation (one spine and nine rib-based). Mean preoperative scoliosis was 64°, postimplant 52°, and at mean follow up of 2.4 ± 0.5 years was 50° (p = .09). Preoperative kyphosis was 36°, postimplant 38°, and final 42° (p = .08). Preoperative T1-S1 height was 23.5 cm, postimplant 23.6 cm, and final 27.3 cm (p = .06). Preoperative convex hemithoracic height was 10.4 cm, postimplant 7.9 cm, and final 12.8 cm (p < .05). Preoperative concave hemithoracic height was 8.4 cm, postimplant 8.8 cm, and final 9.9 cm (p = .30). Preoperative right hemithoracic width was 8.02 cm, postimplant 7.22 cm, and final 7.86 cm (p = .07). Preoperative left hemithoracic width was 7.18 cm, postimplant 7.86 cm, and final 8.60 cm (p = .43). Eight patients had ≥1 complication with SV I (n = 7), SV II (n = 2), and SV IIA (n = 7). These included infection (n = 4), migration (n = 3), pneumonia (n = 2), and instrumentation failure (n = 2). CONCLUSION: At minimum two-year follow-up, GF surgical intervention for the treatment of EOS associated with Goldenhar syndrome trended toward improvements in scoliosis and spine height, but had a significant improvement in convex hemithoracic height; however, the majority of patients experienced severity grade I or II complications. LEVEL OF EVIDENCE: Level IV.

Complication Severity Score for Growth-friendly Surgery Has Strong Interrater and Intrarater Agreement.

BACKGROUND: Growth-friendly surgery has high complication rates. The Complication Severity Score for growth-friendly surgery was developed to maintain consistency while reporting complications as part of research in this rapidly evolving field. This study evaluates the interrater and intrarater reliability of this complication classification system. METHODS: After Institutional Review Board approval, complications during treatment for early onset scoliosis were identified from a prospectively collected database. Previous validation studies and a 10-case pilot survey determined that 60 cases were needed to represent a minimum of substantial agreement. In total, 63 of 496 cases were selected randomly to evenly represent each severity classification. The cases comprised an internet survey for classification sent to faculty and research coordinators involved in early onset scoliosis research, 3 weeks apart, with questions shuffled between iterations. Fleiss Kappa and Cohen Kappa were used to assess interrater and intrarater agreement, respectively. RESULTS: A total of 20 participants, 12 faculty and 8 research assistants, completed the survey twice. The overall Fleiss Kappa coefficient for interrater agreement from the second round of the survey was 0.86 (95% confidence interval, 0.86-87), which represents substantial agreement. Reviewers agreed almost perfectly on categorizing complications as Device I (0.85), Disease I (0.91), Disease II (0.94), Device IIB (0.92), and Disease IV (0.98). There was substantial agreement for categorizing Device IIA (0.73) and Device III (0.76) complications. Disease III and Device IV were not evaluated in this survey since none of these occurred in the database. There was almost perfect intrarater agreement among faculty (0.87), research coordinators (0.85), and overall (0.86). CONCLUSIONS: There is strong interrater and intrarater agreement for the published complications classification scheme for growing spine surgery. The complication classification system is a reliable tool for standardizing reports of complications with growth-friendly surgery. Adoption of this classification when reporting on growth-friendly surgery is recommended to allow for comparison of complications between treatment modalities. LEVEL OF EVIDENCE: Level I-diagnostic study.

Paper #41: Two Year HRQOL Measures are Similar Between Magnetically-Controlled Growing Rod Patients and Traditional Growing Rod Patients.

Despite having lower HRQoL domain scores pre-operatively, EOS patients treated with magnetically-controlled growing (MCGR) had similar EOSQ-24 domain scores after two years of treatment compared to patients treated with traditional growing rods (TGR).

Paper #30: Congenital Spine Deformity with Fused Ribs Treated with Proximal Rib- vs. Spine-Based Growing Constructs.

179 patients with congenital rib fusions treated with rib-based or spine-based constructs and minimum 2-year follow-up were reviewed. 19 patients were treated with proximal spine-based and 160 with proximal rib-based devices. Patients treated with growing rods achieved equivalent SAL to those treated with rib-based devices, while also achieving greater improvement to their spine deformity, as measured by postoperative kyphosis, and Cobb angle.

Paper #29: Does the Type of Proximal Anchor Used During Distraction-Based Surgeries for Patients With Non-Idiopathic EOS Affect Spine Length?

At minimum 5 yr f/u, distraction-based surgeries (Spine-based (SB)&Rib-based (RB)) are an effective way to increase spine length for non-idiopathic EOS. Spine length is greater for spine based implants pre-operatively and this length is maintained to the 15th lengthening; however, if normalized to pre-op spine length, rib-based implants achieved greater percentage of increase in spine length beyond the 10th lengthening surgeries.

Complications and Radiographic Outcomes of Posterior Spinal Fusion and Observation in Patients Who Have Undergone Distraction-Based Treatment for Early Onset Scoliosis.

STUDY DESIGN: Retrospective, multicenter. OBJECTIVES: To compare surgical and radiographic outcomes of early-onset scoliosis (EOS) patients who had stopped lengthening for ≥2 years without additional surgery to those who had posterior spinal fusion (PSF) at the end of lengthening. SUMMARY OF BACKGROUND DATA: Because of the risk of significant complications with PSF in patients with EOS, "watchful waiting" at the end of lengthening has been suggested as a viable alternative. METHODS: Retrospective review of the Children's Spine Study Group (CSSG) database identified all patients with the diagnosis of EOS who had distraction-based treatment, who were ≥2 years from their last distraction, and who had complete records. Radiographic measures were obtained by a single unbiased trained observer. Treatment outcomes including curve correction, height and length gain, as well as complications were recorded. RESULTS: The 37 patients (21 females and 16 males) had a mean age of 7.2 years; 12 were in the observation (OBS) and 25 in the PSF group. The PSF group had a slightly greater coronal Cobb angle and maximal kyphosis at the end of distraction. Although there was some correction of the coronal Cobb angle and maximal kyphosis following PSF, the differences between the two groups were not statistically significant at final follow-up. At final follow-up, the OBS group obtained 88% of T1-T12 height and 90% of T1-L1 length of that obtained by the PSF group. Twenty-six complications occurred in 15 patients, all in the PSF group. CONCLUSIONS: Observation may be a viable alternative to PSF after distraction-based treatment in a subset of patients with EOS. PSF was found to provide no significant curve correction or gains in spine height and length compared to observation and carries a significant risk of complications. LEVEL OF EVIDENCE: Level III, therapeutic.