The Longitudinal Effects of Posterior Spinal Fusion with Derotation on Axial Deformity in Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To characterize the change in angle of trunk rotation (ATR), axial vertebral rotation (AVR), and body surface rotation (BSR) in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with en-bloc derotation across multiple postoperative visits. SUMMARY OF BACKGROUND DATA: Previous research has documented ATR, AVR, and BSR correction for AIS patients after surgery. However, there is a lack of evidence on the sustainability of this correction over time. METHODS: This was a retrospective study from a single-center prospective surface topographic registry of patients with AIS, age 11-20 at time of surgery, who underwent PSF with en-bloc derotation. Patients with previous spine surgery were excluded. ATR was measured with a scoliometer, AVR through EOS radiographic imaging, and BSR via surface topographic scanning, Data collection occurred at: preoperative, six-week, three-month, six-month, one-year, and two-year postoperative visits. BSR and AVR were tracked at the preoperative apical vertebral level, and the level with maximum deformity, at each respective timepoint. Generalized estimating equations models were used for statistical analysis. Covariates included age, sex, and body mass index. RESULTS: 49 patients (73.4% female, mean age 14.6±2.2 years, mean preoperative coronal curve angle 57.9°±8.5, and 67% major thoracic) were evaluated. ATR correction was significantly improved at all postoperative timepoints and there was no significant loss of correction. AVR Max and AVR Apex were significantly improved at all timepoints but there was a significant loss of correction for AVR Apex between the six-week and one-year visit (P=0.032). BSR Max achieved significant improvement at the three-month visit. BSR Apex was significantly improved at the three-month and one-year visit. CONCLUSION: ATR and AVR demonstrated significant axial plane correction at two-years postoperative in patients undergoing PSF for AIS. BSR did not maintain significant improvement by the two-year visit.

Utilizing robotic-assisted navigation for pelvic instrumentation in pediatric patients with neuromuscular scoliosis: a technical note and case series.

Pelvic fixation is commonly used in correcting pelvic obliquity in pediatric patients with neuromuscular scoliosis and in preserving stability in adult patients with lumbosacral spondylolisthesis or instances of traumatic or osteoporotic fracture. S2-alar-iliac screws are commonly used in this role and have been proposed to reduce implant prominence when compared to traditional pelvic fusion utilizing iliac screws. The aim of this technical note is to describe a technique for robotically navigated placement of S2-alar-iliac screws in pediatric patients with neuromuscular scoliosis, which (a) minimizes the significant exposure needed to identify a bony start point, (b) aids in instrumenting the irregular anatomy often found in patients with neuromuscular scoliosis, and (c) allows for greater precision than traditional open or fluoroscopic techniques. We present five cases that underwent posterior spinal fusion to the pelvis with this technique that demonstrate the safety and efficacy of this procedure.

Hemiepiphysiodesis for Genu Valgum in Patients With Multiple Hereditary Exostoses.

BACKGROUND: Genu valgum is a well-known feature of multiple hereditary exostoses (MHE). Though prior reports have demonstrated successful treatment with hemiepiphysiodesis, details regarding the correction rate and comparison to an idiopathic population are lacking. This study aimed to detail our institution's experience with guided growth of the knee in patients with MHE and compare this to an idiopathic population. METHODS: All pediatric patients (age 18 and younger) with MHE who underwent lower extremity hemiepiphysiodesis at a tertiary care medical center between January 2016 and December 2022 were retrospectively reviewed. Preoperative and postoperative mechanical lateral distal femoral angle (mLDFA) and medial proximal tibial angle (MPTA, the primary outcomes) were measured in addition to mechanical axis deviation (MAD) and hip-knee-ankle angle (HKA). Patients were 1:2 matched based on age, sex, and physes instrumented to a cohort with idiopathic genu valgum. RESULTS: A total of 21 extremities in 16 patients with MHE underwent hemiepiphysiodesis of the distal femur, proximal tibia, and/or distal tibia. The mean age at surgery was 11.7±2.2 years. Mean MAD corrected from zone 1.9±0.7 to -0.3±1.5, while mLDFA corrected from 83.4±2.9 to 91.7±5.2 degrees and MPTA corrected from 95.3±3.6 to 90.5±4.0 degrees in distal femurs and proximal tibias undergoing guided growth, respectively. Three extremities (14.3%) experienced overcorrection ≥5 degrees managed with observation. There were no differences in correction rates per month for mLDFA (0.54±0.34 vs. 0.51±0.29 degrees, P =0.738) or MPTA (0.31±0.26 vs. 0.50±0.59 degrees, P =0.453) between MHE and idiopathic groups. For 11 extremities in the MHE group with open physes at hardware removal, they experienced a mean recurrence of HKA of 4.0±3.4 degrees at 19-month follow-up. CONCLUSION: Hemiepiphysiodesis corrects lower extremity malalignment in patients with MHE at a similar rate compared with an idiopathic coronal plane deformity population. Rebound deformity of 4 degrees at 19 months after hardware removal in patients with remaining open growth plates should make surgeons conscious of the remaining growth potential when planning deformity correction. LEVEL OF EVIDENCE: Level III.

Analysis of 5,070 consecutive pedicle screws placed utilizing robotically assisted surgical navigation in 334 patients by experienced pediatric spine deformity surgeons: surgical safety and early perioperative complications in pediatric posterior spinal fusion.

PURPOSE: This study evaluates the intraoperative and short-term complications associated with robotically assisted pedicle screw placement in pediatric posterior spinal fusion (PSF) from three surgeons at two different institutions. METHODS: We retrospectively reviewed 334 pediatric patients who underwent PSF with robotic-assisted navigation at 2 institutions over 3 years (2020-2022). Five thousand seventy robotically placed screws were evaluated. Data collection focused on intraoperative and early postoperative complications with minimum 30-day follow-up. Patients undergoing revision procedures were excluded. RESULTS: Intraoperative complications included 1 durotomy, 6 patients with neuromonitoring alerts not related to screw placement, and 62 screws (1.2%) with documented pedicle breaches, all of which were revised at time of surgery. By quartile, pedicle breaches statistically declined from first quartile to fourth quartile (1.8% vs. 0.56%, p < 0.05). No breach was associated with neuromonitoring changes or neurological sequelae. No spinal cord or vascular injuries occurred. Seventeen postoperative complications occurred in eleven (3.3%) of patients. There were five (1.5%) patients with unplanned return to the operating room. CONCLUSION: Robotically assisted pedicle screw placement was safely and reliably performed on pediatric spinal deformity by three surgeons across two centers, demonstrating an acceptable safety profile and low incidence of unplanned return to the operating room.

The global impact of the COVID-19 pandemic on pediatric spinal care: A multi-centric study.

Background: The COVID-19 pandemic has affected healthcare worldwide since December 2019. We aimed to identify the effect of the COVID-19 pandemic on outpatient clinic and surgical volumes and peri-operative complications for pediatric spinal deformities patients. Methods: In this multi-center retrospective study, outpatient visits (in-person and virtual care) and pediatric spine surgeries volumes in four high-volume pediatric spine centers were compared between March and December 2019 and the same period in 2020. Peri-operative complications were collected and compared in the same periods. Descriptive statistics were calculated, and comparative analyses were performed. Results: During the 2020 study period, the outpatient visit (in-person and virtual care) volume decreased during local lockdown periods by 71% for new patients (p < 0.001) and 53% for returning patients (p = 0.03). Overall, for 2020, there was a 20% reduction in new patients (p = 0.001) and 21% decrease in returning patients (p < 0.001). During the pandemic, there was also 20% less overall surgical volume of adolescent idiopathic scoliosis (AIS) patients undergoing primary posterior spinal fusion, with a 70% reduction during lockdown times (p < 0.001). Complication rate and profile were similar between periods. Conclusion: There was a significant decrease in outpatient pediatric spine outpatient visits, particularly new patients, which may increase the proportion of pediatric patients with spinal deformities that present late, meeting surgical indication. This, in combination with the reduction in surgical volume of AIS over the first year of the pandemic, could result in an extended waitlist for surgeries during years to come. Complication rate was similar for both periods, suggesting it is safe to continue elective pediatric spine surgery even in a time of a pandemic. Level of evidence: level IV.

High Rates of Successful Return to Competitive Athletics After Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis Regardless of Distal Fusion Level: A Prospective Cohort Study.

STUDY DESIGN: Prospective cohort. OBJECTIVE: To determine if distal spinal fusion level is associated with postoperative sport participation after posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: The concept of "saving a level" during PSF for AIS refers to minimizing the distal extent of lumbar fusion to theoretically allow for increased postoperative spinal mobility and a more predictable return to athletic activity, as well as minimizing the risk of degenerative disc disease. There are few prospective studies evaluating the correlation between distal fusion level and timing of return to sports. MATERIALS AND METHODS: Adolescent patients undergoing PSF for AIS between 2009 and 2019 were approached at their presurgical visit to participate in this prospective study. Participants were followed for a minimum of 2 years after surgery. Sports participation (classified by sport type and level of competitiveness) and radiographic data were collected at the initial visit. At each postoperative visit, it was noted whether patients returned to the same sport type and level of competitiveness. RESULTS: After an a priori power calculation was performed, a total of 106 participants were included in the analysis with a mean age of 14 ± 2 years. Distal fusion levels ranged from T11 to L4. There was no significant association between distal fusion level and return to the same level of sports participation ( P = 0.192). Of the participants, 93% returned to sports with no significant differences by distal fusion level ( P = 0.081). Distal fusion level demonstrated no difference in return to preoperative sport ( P = 0.486) or return to the same type of sport ( P = 0.247). CONCLUSIONS: This study found no association between distal fusion level and postoperative sports participation. Even though many patients may elect to change sports, nearly all patients returned to sports, and the majority of patients returned to the same level of sports competition or higher after PSF for AIS.

Advances in robotics and pediatric spine surgery.

PURPOSE OF REVIEW: Robotic-assisted surgical navigation for placement of pedicle screws is one of the most recent technological advancements in spine surgery. Excellent accuracy and reliability results have been documented in the adult population, but adoption of robotic surgical navigation is uncommon in pediatric spinal deformity surgery. Pediatric spinal anatomy and the specific pediatric pathologies present unique challenges to adoption of robotic assisted spinal deformity workflows. The purpose of this article is to review the safety, accuracy and learning curve data for pediatric robotic-assisted surgical navigation as well as to identify "best use" cases and technical tips. RECENT FINDINGS: Robotic navigation has been demonstrated as a safe, accurate and reliable method to place pedicle screws in pediatric patients with a moderate learning curve. There are no prospective studies comparing robotically assisted pedicle screw placement with other techniques for screw placement, however several recent studies in the pediatric literature have demonstrated high accuracy and safety as well as high reliability. In addition to placement of pediatric pedicle screws in the thoracic and lumbar spine, successful and safe placement of screws in the pelvis and sacrum have also been reported with reported advantages over other techniques in the setting of high-grade spondylolisthesis as well as pelvic fixation utilizing S2-alar iliac (S2AI) screws. SUMMARY: Early studies have demonstrated that robotically assisted surgical navigation for pedicle screws and pelvic fixation for S2AI screws is safe, accurate, and reliable in the pediatric population with a moderate learning curve.

Reliability of automated topographic measurements for spine deformity.

PURPOSE: This study introduces a novel surface-topographic scanning system capable of automatically generating a suite of objective measurements to characterize torso shape. RESEARCH QUESTION: what is the reliability of the proposed system for measurement of trunk alignment parameters in patients with adolescent idiopathic scoliosis (AIS) and controls? METHODS: Forty-six adolescents (26 with AIS and 20 controls) were recruited for a prospective reliability study. A series of angular, volumetric, and area measures were computed from topographic scans in each of three clinically relevant poses using a fully automated processing pipeline. Intraclass correlation coefficients (ICC(2,1)) were computed within (intra-) and between (inter-) raters. Measurements were also performed on a torso phantom. RESULTS: Topographic measurements computed on a phantom were highly accurate (mean RMS error 1.7%) compared with CT. For human subjects, intra- and inter-rater reliability were both high (average ICC > 0.90) with intrinsic (pose-independent) measurements having near-perfect reliability (average ICC > 0.98). CONCLUSION: The proposed system is a suitable tool for topographic analysis of AIS; topographic measurements offer an objective description of torso shape that may complement other imaging modalities. Further research is needed to compare topographic findings with gold standard imaging of spinal alignment, e.g., standing radiography. CONCLUSION: clinical parameters can be reliably measured in a fully automated system, paving the way for objective analysis of symmetry, body shape pre/post-surgery, and tracking of pathology without ionizing radiation.

Less Invasive Pediatric Spinal Deformity Surgery: The Case for Robotic-Assisted Placement of Pedicle Screws.

Introduction: Pediatric spinal deformity involves a complex 3-dimensional (3D) deformity that increases the risk of pedicle screw placement due to the close proximity of neurovascular structures. To increase screw accuracy, improve patient safety, and minimize surgical complications, the placement of pedicle screws is evolving from freehand techniques to computer-assisted navigation and to the introduction of robotic-assisted placement. Purpose: The aim of this review was to review the current literature on the use of robotic navigation in pediatric spinal deformity surgery to provide both an error analysis of these techniques and to provide recommendations to ensure its safe application. Methods: A narrative review was conducted in April 2021 using the MEDLINE (PubMed) database. Studies were included if they were peer-reviewed retrospective or prospective studies, included pediatric patients, included a primary diagnosis of pediatric spine deformity, utilized robotic-assisted spinal surgery techniques, and reported thoracic or lumbar pedicle screw breach rates or pedicle screw malpositioning. Results: In the few studies published on the use of robotic techniques in pediatric spinal deformity surgery, several found associations between the technology and increased rates of screw placement accuracy, reduced rates of breach, and minimal complications. All were retrospective studies. Conclusions: Current literature is of a low level of evidence; nonetheless, the findings suggest the accuracy and safety of robotic-assisted spinal surgery in pediatric pedicle screw placement. The introduction of robotics may drive further advances in less invasive pediatric spinal deformity surgery. Further study is warranted.

Evaluation of K-wireless robotic and navigation assisted pedicle screw placement in adult degenerative spinal surgery: learning curve and technical notes.

BACKGROUND: K-wireless robotic pedicle screw instrumentation with navigation is a new technology with large potential. Barriers to adoption are added registration time with robotic-navigated system and reliable screw positioning. Understanding the learning curve and limitations is crucial for successful implementation. The purpose of this study was to describe a learning curve of k-wireless robotic assisted pedicle screw placement with navigation and compare to conventional techniques. METHODS: A retrospective review of prospectively collected data of 65 consecutive adult patients underwent robotic-navigated posterior spinal fusion by a single spine surgeon. Registration, screw placement, and positioning times were recorded. All patients underwent intra-operative 3D fluoroscopy and screw trajectory was compared to pre-operative CT. RESULTS: A total of 364 instrumented pedicles were planned robotically, 311 (85.4%) were placed robotically; 17 screws (4.7%) converted to k-wire, 21 (5.8%) converted to freehand, and 15 (4.1%) planned freehand. Of the 311 robotically placed pedicle screws, three dimensional fluoroscopic imaging showed 291 (93.5%) to be GRS Grade A in the axial plane (fully contained within the pedicle) and 281 (90.4%) were GRS Grade A in the sagittal plane. All breached screw deviations from plan were identified on 3D fluoroscopy during surgery and repositioned and confirmed by additional 3d fluoroscopy scan. Reasons for conversion included morphology of starting point (n=18), soft tissue pressure (n=9), hypoplastic pedicles (n=6), obstructive reference pin placement (n=2), and robotic arm issues (n=1). Seventeen (5.5%) critical breaches (≥2-4 mm) were recorded in 11 patients, 9 (2.9%) critical breaches were due to soft tissue pressure causing skive. Two patients experienced 6 (1.9%) critical breaches from hypoplastic pedicles, and 3 (0.9%) unplanned lateral breaches were found in another patient. One patient (0.3%) experienced skive due to morphology and spinal instability from isthmic spondylolisthesis. Imaging showed 143 screws placed medially to plan (1.2±0.9 mm), 170 lateral (1.2±1.1 mm), 193 screws caudal (1.0±0.6 mm) and 117 cranial (0.6±0.5 mm). No adverse clinical sequelae occurred from implantation of any screw. CONCLUSIONS: The learning curve showed improvement in screw times for the first several cases. Understanding the learning curve and situations where the robotic technique may be suboptimal can help guide the surgeon safe and effectively for adoption, as well as further refine these technologies.

Comprehensive Error Analysis for Robotic-assisted Placement of Pedicle Screws in Pediatric Spinal Deformity: The Initial Learning Curve.

BACKGROUND: Surgical navigation improves pedicle screw insertion accuracy and reliability. Robotic-assisted spinal surgery and screw placement has not been fully assessed in pediatric patients with spine deformity undergoing posterior spinal fusion. The purpose of this study was to describe the learning curve for robotically assisted pedicle screw placement in pediatric patients. METHODS: A retrospective review on a consecutive series of the first 19 pediatric patients who underwent posterior spinal fusion by a single surgeon using robotic navigation was performed. Demographics, curve parameters, pedicle diameter, vertebral rotation, and additional outcome measures were recorded. Screw position was assessed with calibrated intraoperative 3-dimensional fluoroscopic images. All complications of planned and placed robotically placed screws were recorded. RESULTS: A total of 194 left-sided screws were planned as robot-assisted. One hundred sixty-eight of the robotically planned screws (86.6%) were placed with robot assistance; 29 robotically planned screws (15.0%) were abandoned or converted to freehand. The mean time per robotically placed screw was 3.6±2.4 minutes. Fifteen breaches (8.9%) and 1 anterior perforation occurred with 2 critical (>2 to 4 mm) breaches, 1 was associated with a durotomy, and both occurred in the first case. There were no intraoperative/postoperative neuromonitoring changes and no sequela from the durotomy. Six breaches occurred in the first case. The odds ratio of obtaining a breach in screws with a matched trajectory was 0.275 (95% confidence interval: 0.089-0.848). CONCLUSIONS: Screw time and accuracy improved and the number of breaches decreased after 10 cases. This series had 2 critical breaches (between 2 and 4 mm) on the first case. Overall, excluding the 2 critical breaches, 98.8% of robotically executed screws were placed without a critical breach, which is comparable to previous pediatric deformity studies. Caution should be exercised during the initial training period to avoid complications as experience and training lead to an improved understanding of surgical planning, skive, and soft-tissue pressure on the end-effector all of which can impact accuracy of robotically assisted pedicle screw placement. LEVEL OF EVIDENCE: Case Series, IV.

The correlation between spinal and chest wall deformities and pulmonary function in Marfan syndrome.

PURPOSE: Scoliosis, chest wall deformities and pulmonary involvement are common features of Marfan syndrome (MFS). We aimed to assess the impact of spinal and chest wall deformities on pulmonary function in paediatric MFS patients with a surgically managed spinal deformity. METHODS: In this multicentre retrospective study, spirometry, lung volumes and radiographic imaging were performed on 26 MFS patients between the ages of seven and 18 years who were undergoing planned spinal fusion surgery for spinal deformity. A correlation analysis assessed the relationship between radiographic measurements of spinal and chest wall deformities and predicted total lung capacity (TLC), forced vital capacity (FVC) and the ratio between forced expiratory volume in one second and FVC (FEV1/FVC). RESULTS: In total, 18 patients (70%) had impaired pulmonary function. Thoracic kyphosis (mean 19.3°; -32° to 54°) had a strong positive correlation with FEV1/FVC (r = 0.65; p < 0.001). Significant decrease in FEV1/FVC below 80% occurred at kyphosis under 15° (p = 0.004). Kyphosis had a moderate negative correlation with FVC (r = -0.43; p = 0.03). Chest wall deformity had a strong negative correlation with FEV1/FVC (r = -0.61; p = 0.001). The magnitude of the thoracic curve (mean 55.2°; 28° to 92°) had a significant moderate negative correlation with TLC (r = -0.45; p = 0.04). CONCLUSION: In MFS, three factors correlate with decreased pulmonary function measures: hypokyphosis, increasing chest wall deformity and increasing coronal curve magnitude. Hypokyphosis and increased chest wall deformity correlated with diminished FEV1/FVC; increasing thoracic spinal curvature with diminished TLC. Further analysis with a larger cohort will help better define the relationship between these deformities and pulmonary function in this unique population. LEVEL OF EVIDENCE: IV.

An Updated Analysis of the Pediatric Section of the Orthopaedic In-Training Examination.

BACKGROUND: An updated analysis of the pediatrics section of the Orthopaedic In-Training Examination (OITE) is helpful for resident education and preparation for the OITE. The purpose of this study is to provide an updated evaluation of the pediatric category of the OITE, and to explore trends in question topics and taxonomy compared with the previously published analysis from 2011 to 2014. METHODS: Five years (2015-2019) of OITE questions, answers, and references were reviewed. The number of pediatric questions per year was recorded, and questions were subcategorized based on topic tested. The presence or absence of imaging or a clinical photograph was noted. Each question was also assigned a cognitive taxonomy level, based on a previously published classification system. RESULTS: The percentage of pediatric questions on the 2015-2019 OITEs averaged 11.4% compared with 12.6% from 2011 to 2014 (P=0.349). The 3 most commonly tested pediatric topics were general trauma (17.8%), elbow trauma (13.2%), and genetic disorders/syndromes (11.2%). There was a significant increase in questions that required diagnosis and interpretation (27.6% vs. 8%, P<0.001) and a slight but not significant decrease in the questions requiring simple knowledge recall (26.3% vs. 35.5%, P=0.120) and decisions about management (46.1% vs. 56.5%, P=0.077). Overall, 65% of questions utilized clinical photographs or imaging studies compared with 62% from 2011 to 2014 (P=0.621). The most common references were the Journal of Pediatric Orthopaedics, Journal of American Academy of Orthopaedic Surgeons, and Journal of Bone and Joint Surgery. Textbooks were cited less frequently than in the past. CONCLUSIONS: While the percentage of pediatric questions on the OITE has remained consistent over time, the percentage of questions requiring diagnosis and interpretation has increased. In addition, questions testing genetic disorders/syndromes have become more prevalent in recent years. The most commonly cited resources were high-impact journal articles, with textbooks cited less frequently than in previous years. CLINICAL RELEVANCE: Knowledge of the most frequently tested topics and resources cited may assist orthopaedic residents in preparing for the OITE and orthopaedic faculty to focus didactic sessions on the most commonly tested topics.

The Epidemiology of Back Pain in American Children and Adolescents.

STUDY DESIGN: Cross-sectional survey. OBJECTIVE: To determine the prevalence of back pain in American children and adolescents, with a focus on anatomic region, duration, severity, and treatment patterns, and to investigate for any predictive variables. SUMMARY OF BACKGROUND DATA: No study has examined the prevalence of back pain in American children and adolescents in the last 15 years. Because the prevalence of back pain varies greatly by country and year of investigation, previous studies are not generalizable. METHODS: A United States epidemiologic cross-sectional survey-based investigation was performed in children and adolescents ages 10 and 18 years old, equally split by age and sex, and representing census-weighted distributions of state of residence, race/ethnicity, and health insurance status. Prevalence of back pain was evaluated and described. RESULTS: In total, 1236 (33.7%) participants reported experiencing back pain within the last year and 325 (8.9%) reported severe back pain within the last year. Prevalence of back pain increased with age and was significantly more common in females, P < 0.001 for both. Treatment for back pain was sought by 505 (40.9%) of the participants with pain, of which physical therapy was the most common. Invasive procedural treatment (e.g., injections, surgery) were rare and comprised only 61 (1.6%) of study participants. In addition, government insurance and lack of insurance coverage was associated with low treatment seeking behavior compared to private insurance users (P = 0.010 and P = 0.006, respectively). CONCLUSION: Despite how commonly it presents, the majority of young patients with back pain do not report procedural treatment such as injections or surgery. However, because many American children and adolescents seek treatment, future research on the etiology, treatment, and prevention of back pain in children and adolescents is essential to reducing a common and financially demanding problem. LEVEL OF EVIDENCE: 4.

Biomechanical Comparison of Two Pediatric Blade Plate Designs in Proximal Femoral Osteotomies.

BACKGROUND: Blade plates are frequently used for internal fixation following proximal femoral varus rotational osteotomy to treat hip dysplasia in children with cerebral palsy. Recently, cannulated blade plates with the option for a proximal locking screw have demonstrated ease of insertion and low complication rates. Although there are two commonly used blade plates with a proximal screw option, no comparison of their biomechanical profiles has been undertaken. QUESTIONS/PURPOSES: Our study sought to compare the structural properties under axial loading, as well as the biomechanical contribution of a proximal screw, of two different 90° cannulated blade plates designed for pediatric proximal femurs. Plate A has a hole distal to the blade designed to attach a plate inserter, through which a 3.5-mm non-locking cortical screw could be placed. Plate B has a threaded hole distal to the blade designed to accept a 3.5-mm locking screw. METHODS: Plate A and plate B were inserted into 33 left pediatric synthetic proximal femurs. Axial loading to failure of plate A with and without a proximal screw was compared to that of plate B with and without a proximal screw. An additional 10 samples using plate B, with and without a proximal locking screw, were tested in tension to quantify the effect of the proximal screw on pullout strength. RESULTS: Plate B failed at a higher axial load than plate A. The addition of a proximal screw did not affect the axial load to failure for either plate. Pullout testing revealed that blade plates fixed with the proximal screw failed in tension at a significantly higher load (856.3 ± 120.9 N) than those without proximal fixation (68.1 ± 9.3 N, p < 0.001). CONCLUSIONS: Plate B failed at a higher axial load in biomechanical testing, likely related to differences in its design. The addition of a proximal screw did not increase the axial loading properties of the blade plate construct but did increase the pullout strength by a factor of 12. These results may be used to influence implant selection and post-operative rehabilitation following proximal femoral osteotomies in children.

Ultrasound Is an Alternative to X-ray for Diagnosing Developmental Dysplasia of the Hips in 6-Month-Old Children.

BACKGROUND: Infants previously treated for developmental dysplasia of the hips (DDH) are routinely imaged with ultrasound initially and reimaged with an anteroposterior (AP) pelvis X-ray at 6 months of age to assess for dysplasia. It has become convention to transition from ultrasound to AP X-ray at 6 months of age, but no study has demonstrated that ultrasound is inadequate at this age. QUESTION/PURPOSE: The purpose of this study was to confirm that ultrasound for the 6-month DDH evaluation is a feasible alternative to the standard X-ray. PATIENTS AND METHODS: Thirty-one 5- to 7-month-old infants undergoing AP pelvis X-ray related to previous Pavlik harness treatment for DDH or to a history of breech presentation were prospectively enrolled. All patients were imaged with an AP pelvis X-ray and bilateral hip ultrasounds. Three senior orthopedic surgeons unfamiliar with the patient histories evaluated both types of imaging for standard measures of hip dysplasia, including acetabular index (AI), alpha angle, and bony rim percent coverage of the femoral head. Pearson correlation coefficients were calculated for the X-ray and ultrasound measures. RESULTS: Good quality ultrasound images were obtained in all patients, despite the presence of the ossific nucleus in 66% of the hips. All three reviewers correctly diagnosed the one dislocated hip via both X-ray and ultrasound. There were no false negatives on ultrasound, and none of the patients with negative ultrasounds required treatment during the mean 26 months of follow up. An increased AI on X-ray was correlated with lower percent coverage of the femoral head on ultrasound. CONCLUSIONS: Ultrasound is a technically feasible DDH imaging modality that can be used as an alternative to X-ray for 6-month-olds.

Pediatric Septic Arthritis and Osteomyelitis in the USA: A National KID Database Analysis.

BACKGROUND: Prior reports suggest that osteoarticular infections may be increasing over time. QUESTIONS/PURPOSES: We sought to determine if incidence rates, median in-hospital costs, and length of stay (LOS) of osteomyelitis, septic arthritis (SA), and combined infections have changed over time for pediatric patients, and how they compare to previously reported rates. METHODS: The Kids' Inpatient Database (KID), a US national sample of pediatric hospital discharge records from 1997, 2000, 2003, 2006, 2009, and 2012, was used to determine yearly estimated counts of infections in children 20 years of age or younger. US census data was used to calculate yearly incidence rates. Trend tests using linear contrast analysis were used to compare estimated median LOS and inflation-adjusted median costs over time for each type of infection. RESULTS: From 1997 through 2012, the incidence rate of osteomyelitis increased from 7.9 to 10.5 per 100,000, SA was unchanged from 5.3 to 5.2 per 100, and combined infections increased from 0.8 to 1.3 per 100,000. Median LOS from 1997 to 2012 showed no significant change for osteomyelitis (5.0 to 4.9 days), SA (4.4 to 4.1 days), or combined infections (6.5 to 6.8 days). Median in-hospital costs from 1997 to 2012 increased for osteomyelitis ($7735 to $11,823), SA ($5041 to $10,574), and combined infections ($12,691 to $16,260). CONCLUSION: In pediatric patients, the estimated incidence rate of SA appeared stable, while rates of osteomyelitis and combined infections increased. These estimated rates fall within previously reported ranges. Despite stable LOS, costs have increased over time.

The Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS): Normative Data.

BACKGROUND: Recent data have shown an increase in youth sports participation at younger ages, which may be linked to greater musculoskeletal injury risk. The Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS) is a validated 8-item instrument designed to quantify the activity of children between 10 and 18 years old. Normative data on pediatric and adolescent activity level are unknown. PURPOSE: To establish normative activity-level data for American youth and to determine if there is a natural decrease in activity level during adolescence. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A cross-sectional investigation was performed among 2002 US children and adolescents equally split by sex and age and representing census-weighted distributions of state of residency, race/ethnicity, and health insurance status. Respondents completed the HSS Pedi-FABS, as well as survey questions on demographics and sports participation. Normative data were reported with descriptive statistics. Linear regression analysis was performed to determine if there was an effect of age on activity level during adolescence. RESULTS: A total of 2002 respondents completed the survey; the mean age of the respondents at the time of survey completion was 14.0 ± 2.6 years. Mean weekly amount of reported physical activity was 9.3 ± 8.4 hours. HSS Pedi-FABS scores were normally distributed with a mean of 15.4 ± 8.5 points (out of 30 possible points). There was a modest but statistically significant decrease in HSS Pedi-FABS activity scores with increasing age ( r = -0.175, P < .001), corresponding to a linear decrease in activity scores by 27% on average from age 10 to 18 years. CONCLUSION: The current study provides baseline normative data for activity level in a census-weighted representative population sample of 2002 American youth through the use of a validated activity score (HSS Pedi-FABS). There was a modest but statistically significant decrease in activity scores with increasing age. These results will aid future research by providing normative, representative population-level activity data and will help to quantify the natural rate of decreased activity during adolescence.

Reliability of the Modified Clavien-Dindo-Sink Complication Classification System in Pediatric Orthopaedic Surgery.

BACKGROUND: There is no standardized complication classification system that has been evaluated for use in pediatric or general orthopaedic surgery. Instead, subjective terms such as major and minor are commonly used. The Clavien-Dindo-Sink complication classification system has demonstrated high interrater and intrarater reliability for hip-preservation surgery and has increasingly been used within other orthopaedic subspecialties. This classification system is based on the magnitude of treatment required and the potential for each complication to result in long-term morbidity. The purpose of the current study was to modify the Clavien-Dindo-Sink system for application to all orthopaedic procedures (including those involving the spine and the upper and lower extremity) and to determine interrater and intrarater reliability of this modified system in pediatric orthopaedic surgery cases. METHODS: The Clavien-Dindo-Sink complication classification system was modified for use with general orthopaedic procedures. Forty-five pediatric orthopaedic surgical scenarios were presented to 7 local fellowship-trained pediatric orthopaedic surgeons at 1 center to test internal reliability, and 48 scenarios were then presented to 15 pediatric orthopaedic surgeons across the United States and Canada to test external reliability. Surgeons were trained to use the system and graded the scenarios in a random order on 2 occasions. Fleiss and Cohen kappa (κ) statistics were used to determine interrater and intrarater reliabilities, respectively. RESULTS: The Fleiss κ value for interrater reliability (and standard error) was 0.76 ± 0.01 (p < 0.0001) and 0.74 ± 0.01 (p < 0.0001) for the internal and external groups, respectively. For each grade, interrater reliability was good to excellent for both groups, with an overall range of 0.53 for Grade I to 1 for Grade V. The Cohen κ value for intrarater reliability was excellent for both groups, ranging from 0.83 (95% confidence interval [CI], 0.71 to 0.95) to 0.98 (95% CI, 0.94 to 1.00) for the internal test group and from 0.83 (95% CI, 0.73 to 0.93) to 0.99 (95% CI, 0.97 to 1.00) for the external test group. CONCLUSIONS: The modified Clavien-Dindo-Sink classification system has good interrater and excellent intrarater reliability for the evaluation of complications following pediatric orthopaedic upper extremity, lower extremity, and spine surgery. Adoption of this reproducible, reliable system as a standard of reporting complications in pediatric orthopaedic surgery, and other orthopaedic subspecialties, could be a valuable tool for improving surgical practices and patient outcomes.

Percutaneous Epiphysiodesis Using Transphyseal Screws: a Case Series Demonstrating High Efficacy.

BACKGROUND: Percutaneous epiphysiodesis using transphyseal screws (PETS) has been associated with implant failure, implant prominence, angular deformities, and delayed growth inhibition. QUESTIONS/PURPOSES: The aim of this study was to assess the complication rate and efficacy (defined as actual growth inhibition divided by expected growth inhibition) of PETS and to identify factors associated with improved efficacy. METHODS: Patients who underwent distal femoral and/or proximal tibial PETS between January 2007 and June 2014 were identified. Complications, efficacy, and final limb-length discrepancy (LLD) were calculated using multipliers and inhibition rates based on previous growth. Associations between efficacy and screw insertion angle (SIA), body mass index, and number of threads crossing the physis were calculated. RESULTS: Eight-two patients (126 treated physes) were included. The mean pre-operative LLD was 27.7 mm (SD = 7.5). Following epiphysiodesis, 15 had temporary pain (18%), five had temporary effusion (6.1%), four had broken implants (4.9%), four developed mild angulation (4.9%), and three had failed epiphysiodesis requiring revision (3.7%). Thirty-one underwent screw removal (n = 31, 38%). Mean LLD at maturity was 17.3 mm (SD = 5.8 mm). Mean efficacy at the distal femur was 97% (SD = 46%), at the proximal tibia was 108% (SD = 66%) and was 103% (SD = 57%) overall. Increased screw threads across the lateral proximal tibial physis (Spearman's correlation coefficient = 0.67; 95% CI = 0.40-0.94) and higher BMI (Spearman's correlation coefficient = 0.55; 95% CI = 0.34-0.77) were positively associated with increased efficacy. CONCLUSIONS: The efficacy of PETS may be more favorable than previously reported. Only 3.7% had serious complications requiring revision epiphysiodesis, lower than previous reports. Attention to sufficient screw threads across the physis may be important in optimizing PETS results.