Clinically significant proximal junctional kyphosis (PJK) occurs in 20% of children treated with posterior distraction-based growth friendly surgery. In an effort to identify modifiable risk factors, it has been theorized biomechanically that low radius of curvature (ROC) implants (i.e., more curved rods) may increase post-operative thoracic kyphosis, and thus may pose a higher risk of developing PJK. We sought to test the hypothesis that EOS patients treated with low ROC (more curved rods) distraction-based treatment will have a greater risk of developing PJK as compared to those treated with high ROC (straighter) implants.

This is a retrospective review of prospectively collected data obtained from a multi-centre EOS database on children treated with rib-based distraction with minimum 2-year follow-up. Variables of interest included: implant ROC at index (220 mm or 500 mm), patient age, pre-operative scoliosis, pre-operative kyphosis, and scoliosis etiology. In the literature, PJK has been defined as clinically significant if revision surgery with superior extension of the upper instrumented vertebrae was performed.

In 148 scoliosis patients, there was a higher risk of clinically significant PJK with low ROC (more curved) rods (OR: 2.6 (95%CI 1.09-5.99), χ2 (1, n=148) = 4.8, p = 0.03). Patients had a mean pre-operative age of 5.3 years (4.6y 220 mm vs 6.2y 500 mm, p = 0.002). A logistic regression model was created with age as a confounding variable, but it was determined to be not significant (p = 0.6). Scoliosis etiologies included 52 neuromuscular, 52 congenital, 27 idiopathic, 17 syndromic with no significant differences in PJK risk between etiologies (p = 0.07). Overall, patients had pre-op scoliosis of 69° (67° 220mm vs 72° 500mm, p = 0.2), and kyphosis of 48° (45° 220mm vs 51° 500mm, p = 0.1). The change in thoracic kyphosis pre-operatively to final follow up (mean 4.0 ± 0.2 years) was higher in patients treated with 220 mm implants compared to 500 mm implants (220 mm: 7.5 ± 2.6° vs 500 mm: −4.0 ± 3.0°, p = 0.004).

Use of low ROC (more curved) posterior distraction implants is associated with a significantly greater increase in thoracic kyphosis which likely led to a higher risk of developing clinically-significant PJK in EOS patients.

Scoliosis is estimated to occur between 21–64% of patients with cerebral palsy (CP), where a subset of patients develops early onset scoliosis (EOS) before the age of ten. Traditional growth friendly (TGF) surgeries in the context of traditional growing rods have been shown to be effective in treating scoliosis in this population, however significant complication rates are reported. Currently, no studies have been done to examine the effect of novel growth friendly surgeries such as magnetically controlled growing rods (MCGR) on EOS in CP patients. The objective of this study is to compare MCGR with TGF surgeries in this patient population, specifically by evaluating radiographic measurements and risk of unplanned reoperations (UPRORs).

Patients with EOS secondary to CP were prospectively identified from an international database, with data retrospectively analyzed. Scoliosis (primary curve), maximum kyphosis, T1-S1 and T1-T12 height were measured pre-operation, immediate post-operation, and at two-years follow-up. The risk and etiology of UPRORs were compared between MCGR and TGF. P < 0.05 was considered statistically significant for all analyses.

Of the 120 patients that met inclusion criteria, 86 received TGF (age 7.5 ± 1.8 years; follow-up 7.0 ± 2.9 years) and 34 received MCGR (age 7.1 ± 2.2 years, follow-up 2.8 ± 0.5 years). Compared to TGF, MCGR resulted in significant improvements in maintenance of scoliosis correction (p=0.04). At final follow-up, UPRORs were 24% for MCGR (8/34 patients) and 43% (37/86 patients) for TGF (p=0.05). To minimize the influence of follow-up period, UPRORs within the first two years post-operation were evaluated: MCGR (21%, 7/34 patients) vs. TGF (14%, 12/86 patients; p=0.37). Within the first two years, etiology of UPROR as a percentage of all patients per group were deep infection (5% TGF, 6% MCGR), implant failure/migration (5% TGF, 9% MCGR), dehiscence (2% TGF, 3% MCGR), and superficial infection (1% TGF, 3% MCGR). The most common etiology of UPROR for TGF was deep infection and implant failure/migration and for MCGR was implant failure/migration.

For patients with CP, at final follow-up, MCGR had superior maintenance of scoliosis correction; however, there was no difference in risk of UPROR within the first two years post-operatively (21% MCGR, 14% TGF).

The purpose of this study was to measure the effect of the implementation of a LEAN continuous process improvement initiative on the waitlist in an ambulatory pediatric orthopaedic clinic.

LEAN is a set of principles that guide organizational thinking and form a comprehensive approach to continuous process improvement. In 2016, our health centre began its journey towards becoming a LEAN organization. The health centre's Strategy and Performance portfolio collaborated with the Orthopaedic Clinic Team to facilitate a Value Stream Analysis, which mapped the clinic process from referral to discharge from care. This informed the plan for targeted improvement events designed to identify and reduce non-value added activity, while partnering with patients and families to share their experiences with care in the clinic. Improvement events included: In-Clinic Patient Flow; Scheduling Process Review; Standardized Triage Process; Clinician Schedule; 5-S Large Cast and Sample Exam Rooms; Booking Orthopedics Clinic; and Travelling and Remote Care. During each event, solutions were identified to improve the patient experience, access, and clinic flow. These solutions have been standardized, documented, and continuously monitored to identify additional improvement opportunities. Comparison of wait-list and percentage of new patients seen within target window was performed from August 2017 to December 2018.

The LEAN initiative resulted in a 48% decrease in wait-list for new patients, which translated to an improvement from 39% to 70% of new patients seen within their target window. There was a 19% decrease in the 3400+ patient wait-list for follow-up appointments, an 85% reduction in follow-up patients waiting past their target date for an appointment, and the number of patients waiting over a year beyond their target appointment improved from over 300 patients to 0 patients. There was a 15% improvement in average length of clinic visit.

Without the addition of new resources, the implementation of a LEAN continuous process improvement initiative improved the waitlist for new patients in an ambulatory pediatric orthopaedic clinic by almost 50%. Solutions identified and implemented through the LEAN process have contributed to unprecedented improvements in access to care. In fulfilling one of the LEAN theory principles to “pursue perfection”, the paediatric orthopaedic clinic team has embraced a culture of continuous improvement and continues to use LEAN tools such as daily huddles and visual management to monitor solutions and identify gaps.

Proximal junctional kyphosis (PJK) is defined as adjacent segment kyphosis >10° between the upper instrumented vertebrae and the vertebrae 2 levels above following scoliosis surgery. There are few studies investigating the predictors and clinical sequelae involved with this relatively common complication. Our purpose was to determine the radiographic predictors of post-op PJK and to examine the association between PJK and pain/HRQOL following surgery for AIS.

The Post-Operative Recovery after Scoliosis Correction: Home Experience (PORSCHE) study was a prospective multicenter cohort of AIS patients undergoing spinal fusion surgery. Pre-op and minimum 2 year f/u scoliosis and sagittal spinopelvic parameters (thoracic kyphosis–TK, lordosis–LL, pelvic tilt-PT, sacral slope-SS, pelvic incidence-PI) were measured and compared to numeric rating scale for pain (NRS) score, SRS-30 HRQOL and to the presence or absence of PJK (proximal junctional angle >100). Continuous and categorical variables were assessed using logistic regression and binomial variables were compared to binomial outcomes using chi-square.

163 (137 females) patients from 8 Canadian centers met inclusion criteria. At final f/u, PJK was present in 27 patients (17%). Pre-op means for PJK vs No PJK: Age 14.1 vs 14.7yr; females 85 vs 86%; scoliosis 57±22 vs 62±15deg; TK 28±18 vs 19±16deg ∗, LL 62±11 vs 60±12deg, PT 8±12 vs 10±10deg, SS 39±8 vs 41±9deg, PI 47±14 vs 52±13deg, SVA −9±30 vs −7±31mm. Final f/u for PJK vs No PJK: Scoliosis 20±11 vs 18±8deg, final TK 26±12 vs 19±10deg∗, LL 60±11 vs 57±12deg, PT 9±12 vs 12±13deg, SS 39±9 vs 41±9deg, PI 48±17 vs 52±14deg, SVA −23±26 vs −9±32mm∗. Significant findings: Pre-op kyphosis >40deg has an odds ratio (OR) of 4.41 (1.50–12.92) for developing PJK∗. The presence of PJK was not associated with any significant differences in NRS or SRS-30. ∗denotes p<0.05.

This prospective multicenter cohort of AIS patients demonstrated a 17% risk of developing PJK. Pre-op thoracic kyphosis >40deg was associated with the development of PJK; however, the presence of PJK was not associated with increased pain or decreased HRQOL.

Slipped capital femoral epiphysis (SCFE) is traditionally treated with in situ fixation using a threaded screw, leading to physeal arrest while stabilizing the femoral head. Recently, there has been interest in alternative methods of fixation for SCFE, aiming to allow growth and remodelling of the femoral neck postoperatively. One such option is the Free Gliding SCFE Screw (Pega Medical), which employs a telescopic design intended to avoid physeal compression. The objective of this study is to evaluate radiographic changes of the proximal femur following in situ fixation using the Free Gliding SCFE Screw.

This study retrospectively evaluated 28 hips in 14 consecutive patients who underwent in situ hip fixation using the Free Gliding SCFE Screw between 2014 and 2018. Initial postoperative radiographs were compared to last available follow-up imaging. Radiographic assessment included screw length, articulotrochanteric distance (ATD), posterior sloping angle (PSA), alpha angle, head-neck offset (HNO) and head-shaft angle (HSA).

Of the 28 hips reviewed, 17 were treated for SCFE and an additional 11 treated prophylactically. Average age at surgery was 11.7 years, with an average follow-up of 1.44 years. Screw length increased by 2.3 mm (p < 0.001). ATD decreased from 25.4 to 22.2 mm (p < 0.001). Alpha angle decreased from 68.7 to 59.8 degrees (p = 0.004). There was a trend towards an increase in HNO (p = 0.07). There was no significant change in PSA or HAS. There were three complications (two patients with retained broken guide wires, and one patient requiring screw removal for hip pain).

With use of the Free Gliding SCFE Screw, there was evidence of screw expansion and femoral neck remodelling with short-term follow-up. More research is required to determine the long-term impact of these changes on hip function, and to aid in patient selection for this technology.

This study addresses a crucial gap in the knowledge of normative spinal growth in children. The objective of this study is to provide detailed and accurate 3D reference values for global and segmental spinal dimensions in healthy children under the age of 11.

Radiographic spine examinations of healthy children conducted to rule out scoliosis were reviewed in four scoliosis referral centers in North America. All consecutive children aged three to eleven years old with EOS biplanar good quality x-rays, but without diagnosed growth-affecting pathologies, were included. Postero-Anterior and Lateral calibrated x-rays were used for spine 3D reconstruction and computation of vertebral body height and spine length. Median and interquartile range were calculated from cross-sectional data. Smooth centiles growth curves for 3D True Spinal Length (3DTSL) between T1 and S1, as well as for mid-vertebral heights of T5, T12 and L3, where fit and calibrated from data using the Lambda-Mu-Sigma method (GAMLSS package for R). This method automatically selects the best performing distribution from a familly of choices. Tables of centiles were then predicted from the computed models for selected ages.

A total of 638 full spine examinations from asymptomatic patients were reconstructed in 3D, 397 in girls and 241 in boys. Medians and interquartile ranges were calculated for 3DTSL (T1-S1): 285 (24) mm, 314 (26) mm and 349 (31) mm, and for selected vertebral heights T5: 10 (1) mm, 11 (1) mm and 12 (1) mm, T12: 13 (2) mm, 14 (1) mm and 16 (2) mm, and L3: 14 (1) mm, 16 (2) mm and 18 (2) mm, respectively for the 3–6, 6–8 and 8–11 age groups. Centile curves ready for clinical use of the 3DTSL (T1-S1) and of the vertebral heights of T5, T12 and L3 as a function of age were derived for the 5, 10, 25, 50, 75, 90 and 95th centiles. In general, boys presented linear relationships between spinal dimensions and age, and girls presented more diverging trends with increased variance for older ages. Accordingly curves for boys follow the Normal distribution whereas those for girls follow the original Box-Cox-Cole-Green distribution. Model diagnostic tests (normally distributed residuals, adequate wormplots and |Z statistics| < 2) confirmed adequacy of the models and the absence of significant misfit.

Accurate reference values were derived for spinal dimensions in healthy children. Spinal dimension charts showed that the spinal lengths and vertebral heights changed relatively constantly across the age groups closely resembling WHO total body height charts. The reference values will help physicians better assess their patients' growth potential. It could also be used to predict expected spinal dimensions at maturity or changes in pathologic conditions as well as to assess the impact of growth friendly interventions in the correction of spinal deformities.

Radiostereometric analysis (RSA) allows for precise measurement of interbody distances on X-ray images, such as movement between a joint replacement implant and the bone. The low radiation biplanar EOS imager (EOS imaging, France) scans patients in a weight-bearing position, provides calibrated three-dimensional information on bony anatomy, and could limit the radiation during serial RSA studies. Following the ISO-16087 standard, 15 double exams were conducted to determine the RSA precision of total knee arthroplasty (TKA) patients in the EOS imager, compared to the standard instantaneous, cone-beam, uniplanar digital X-ray set-up.

At a mean of 5 years post-surgery, 15 TKA participants (mean 67 years, 12 female, 3 male) were imaged twice in the biplanar imager. To reduce motion during the scan, a support for the foot was added and the scan speed was increased. The voltage was also increased compared to standard settings for better marker visibility over the implant. A small calibration object was included to remove any remaining sway in post-processing.

The 95% confidence interval precision was 0.11, 0.04, and 0.15 mm in the x, y, and z planes, respectively and 0.15, 0.20, and 0.14° in Rx, Ry, and Rz. Two participants had motion artifacts successfully removed during post-processing using the small calibration object.

With faster speeds and stabilization support, this study found an in vivo RSA precision of ≤ 0.15 mm and ≤ 0.20° for TKA exams, which is within published uniplanar values for arthroplasty RSA. The biplanar imager also adds the benefits of weight bearing imaging, 3D alignment measurements, a lower radiation dose, and does not require a reference object due to known system geometry and automatic image registration.

To evaluate the efficacy of VEPTR in preventing further progression of scoliosis without impeding spinal growth in the treatment of children with progressive early onset scoliosis (EOS) without rib abnormalities.

Prospective, multi-center, observational cohort study on patients with EOS treated with VEPTR with 2-year follow up. Data were analysed based on measurements done pre-implant, immediate post-op and at 2-yr f/u.

Sixty-three patients met inclusion: 35 males and 28 females. Mean age at time of implantation was 6.1±2.4 yrs. Etiologies included congenital (n=6), neuromuscular (n=36), syndromic (n=4), and idiopathic (n=17). Mean follow up was 2.2±0.4 yrs. Scoliosis (72o±18o) decreased after implant surgery (47o±17o) followed by slight increase at 2-yr f/u (57o±18o), p<0.0001.

At 2-yr f/u, VEPTR was effective in treating EOS without rib abnormalities with 86% of patients having an improvement in scoliosis and 94% of patients having an increased spinal height as compared to pre-operatively. VEPTR provided greater than 100% of expected age-matched spine growth and the instrumented spinal segment continued to grow during distraction phase. This large prospective, multicentre study demonstrated the ability of VEPTER to effectively treat EOS without rib abnormalities. Goals of preventing further scoliosis progression and of maintaining normal spine growth were achieved.

Purpose

Spinopelvic parameters describe the orientation, shape, and morphology of the spine and pelvis. In children without spinal deformity, these parameters have been shown to change during the first ten years of life; however, spinopelvic parameters have yet to be defined in children with significant Early Onset Scoliosis (EOS). The purpose of this study is to examine the effects of EOS on sagittal spinopelvic alignment.