The effect of surgical time on perioperative complications in adolescent idiopathic scoliosis cases. A propensity score analysis

BACKGROUND

Posterior spinal instrumentation and fusion (PSIF) for adolescent idiopathic scoliosis (AIS) can be lengthy and complication-ridden. The aim of this study was to evaluate the effect of surgical time on perioperative complications in this procedure when controlling for confounding variables with propensity score analysis.

METHODS

This was an IRB-approved review of electronic health records from 2010 to 2019 at a single tertiary care children's hospital. Patients undergoing PSIF were grouped into "short" (< 6 h) or "long" (≥ 6 h) surgical time groups. Outcome measures were estimated blood loss (EBL), cell saver transfusions, packed red blood cell (pRBC) transfusions, length of stay (LOS), intraoperative monitoring (IOM) alerts, hematocrit, ICU transfer, neurologic loss, surgical site infection, and 90-day readmissions. We controlled for age, sex, BMI, curve severity, number of segments fused, and surgeon factors.

RESULTS

After propensity score matching there were 113 patients in each group. The short surgical time group had lower EBL (median 715, IQR 550-900 vs median 875, IQR 650-1100 cc; p < 0.001), received less cell saver blood (median 120, IQR 60-168 vs median 160, IQR 97-225 cc; p = 0.001), received less intraoperative pRBCs (median 0, IQR 0-0 vs median 0, IQR 0-320, p = 0.002), had shorter average LOS (4.8 ± 1.7 vs 5.4 ± 2.5 days; p = 0.039), and fewer IOM alerts (4.3% vs 18%, p = 0.003).

CONCLUSIONS

Patients with shorter surgical times had less blood loss, received less transfused blood, had a shorter LOS, and fewer IOM alerts compared to patients with longer surgical times. Surgical times < 6 h may have safety and efficacy advantages over longer times.

LEVEL OF EVIDENCE

III.

2015-2021 Industry Payments to Pediatric Orthopaedic Surgeons: Analysis of Trends and Characteristics of Top-earning Surgeons

BACKGROUND

Analysis of industry payments to pediatric orthopaedic surgeons last occurred in 2017. We investigated payments to pediatric orthopaedic surgeons from 2015 to 2021 to understand surgeon characteristics associated with increased industry payments.

METHODS

Open Payments Database datasets from 2015 to 2021 were queried for nonresearch payments to pediatric orthopaedic surgeons. Annual aggregates and subcategories were recorded. For surgeons receiving payments in 2021, the Hirsch index (h-index), gender, and US census division were found using the Scopus database, Open Payments Database, and online hospital profiles, respectively. χ 2 , Fisher exact, Mann-Whitney U , and t tests were used to compare surgeons in the top 25%, 10%, and 5% payment percentiles to the bottom 75%, 90%, and 95%, respectively.

RESULTS

Payments rose 125% from 2015 to 2021. Education, royalties, and faculty/speaker increased most, while travel/lodging, honoraria, charitable contributions, and ownership interest decreased. Only royalties increased from 2019 to 2021. In 2021, of 419 pediatric orthopaedic surgeons receiving industry payments, men received greater median aggregate payments than women ($379.03 vs. $186.96, P =0.047). There were no differences in gender proportions between the top 75% and bottom 25% ( P =0.054), top 10% and bottom 90% ( P =0.235), and top 5% and bottom 95% ( P =0.280) earning comparison groups. The h-index was weakly positively correlated with industry payments ( rs =0.203, P <0.001). Mean h-indices in the 75th ( P <0.001, 95% CI: 2.62-7.65), 90th ( P =0.001, 95% CI: 3.28-13.03), and 95th ( P =0.005, 95% CI: 4.25-21.11) percentiles were significantly higher. Proportions of surgeons from the Middle Atlantic and West South Central in the 90th ( P =0.025) and 95th percentiles ( P =0.033), respectively, were significantly lower compared to all other regions. A higher proportion of surgeons from the Pacific were placed in the 90th ( P =0.004) and 95th ( P =0.024) percentiles.

CONCLUSIONS

Industry payments to pediatric orthopaedic surgeons rose from 2015 to 2021. Most categories fell from 2019 to 2021, which may be related to the SARS-CoV-19 pandemic. In 2021, though gender was not related to aggregate payment percentile, location in select US census divisions and h-index was.

LEVEL OF EVIDENCE

Level II-Retrospective study.

BrAIST-Calc: Prediction of Individualized Benefit From Bracing for Adolescent Idiopathic Scoliosis

STUDY DESIGN

Prospective multicenter study data were used for model derivation and externally validated using retrospective cohort data.

OBJECTIVE

Derive and validate a prognostic model of benefit from bracing for adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

The Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST) demonstrated the superiority of bracing over observation to prevent curve progression to the surgical threshold; 42% of untreated subjects had a good outcome, and 28% progressed to the surgical threshold despite bracing, likely due to poor adherence. To avoid over-treatment and to promote patient goal setting and adherence, bracing decisions (who and how much) should be based on physician and patient discussions informed by individual-level data from high-quality predictive models.

MATERIALS AND METHODS

Logistic regression was used to predict curve progression to <45° at skeletal maturity (good prognosis) in 269 BrAIST subjects who were observed or braced. Predictors included age, sex, body mass index, Risser stage, Cobb angle, curve pattern, and treatment characteristics (hours of brace wear and in-brace correction). Internal and external validity were evaluated using jackknifed samples of the BrAIST data set and an independent cohort (n=299) through estimates of discrimination and calibration.

RESULTS

The final model included age, sex, body mass index, Risser stage, Cobb angle, and hours of brace wear per day. The model demonstrated strong discrimination ( c -statistics 0.83-0.87) and calibration in all data sets. Classifying patients as low risk (high probability of a good prognosis) at the probability cut point of 70% resulted in a specificity of 92% and a positive predictive value of 89%.

CONCLUSION

This externally validated model can be used by clinicians and families to make informed, individualized decisions about when and how much to brace to avoid progression to surgery. If widely adopted, this model could decrease overbracing of AIS, improve adherence, and, most importantly, decrease the likelihood of spinal fusion in this population.

Biomechanical analysis of rod contouring in posterior spinal instrumentation and fusion for 3D correction of adolescent idiopathic scoliosis

PURPOSE

To biomechanically evaluate 3D corrective forces and deformity correction attributable to key parameters of rod contouring in posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS).

METHODS

Computerised patient-specific biomechanical models of six AIS cases were used to simulate PSF and evaluate the effects of 5.5-mm cobalt-chrome rod contouring angle (concave-convex angles: 30°-15°, 45°-15° and 60°-15°), length (spanning 4 and 7 vertebrae), and apex location (T7, T9). 3D correction and bone-implant forces were computed and analysed.

RESULTS

By increasing the concave rod contour from 30° to 60°, thoracic kyphosis (TK) increased from 18° ± 2° (15°-19°) to 24° ± 2° (22°-26°), apical vertebra rotation (AVR) correction increased from 41% (SD8%) to 66% (SD18%) whilst the main thoracic curve (MT) correction decreased from 68% (SD6%) to 56% (SD8%). With a contouring length of 4 vs. 7 vertebrae, the resulting TK, AVR and MT corrections were 22° ± 1° (19°-26°) vs. 19° ± 10° (15°-22°), 57% (SD18%) vs. 50% (SD26%) and 59% (SD1%) vs. 69% (SD35%), respectively. With the rod contouring apex at T7 (vs. T9), AVR corrections were 69% (SD19%) vs. 44% (SD9%), with no significant difference in TK and MT corrections, and with comparatively 67% of screw pull-out forces. Corrective forces were more evenly shared with fixation on 7 vs. 4 vertebrae.

CONCLUSION

Rod contouring of a greater angulation, over a shorter portion of the rod, and more centred at the apex of the main thoracic curve apex improved AVR correction and allowed greater restoration of TK, but resulted in significantly higher screw pull-out forces and came at the expense of less coronal plane correction.

Concave rod first vs. convex rod first in AIS instrumentation with differential rod contouring: computer modeling and simulations based on ten AIS surgical cases

PURPOSE

To assess biomechanical differences between AIS instrumentations using concave vs. convex rod first.

METHODS

Instrumentations of ten AIS patients were simulated first with major correction maneuvers using the concave rod then with convex rod. Correction maneuvers were concave/convex rod translation, followed by apical vertebral derotation and then convex/concave rod translation. The concave/convex rods were 5.5/5.5 and 6.0/5.5 mm diameter Co-Cr and contoured to 35°/15°, 55°/15°, 75°/15° and 85°/15°, respectively.

RESULTS

Differences in simulated thoracic Cobb angle (MT), thoracic kyphosis (TK) and apical vertebral rotation (AVR) were less than 5° between the two techniques; mean bone-screw force difference was less then 15N (p > 0.1). Increasing differential contouring angle from 35°/15° to 85°/15°, the MT changed from 14 ± 7° to 15 ± 8°, AVR from 12 ± 4° to 6 ± 5°, TK from 23 ± 4° to 42 ± 4°, and bone-screw forces from 159 ± 88N to 329 ± 170N (P < 0.05). Increasing the concave rod diameter from 5.5 to 6 mm, the mean MT correction improvement for both techniques was less than 2°, the AVR correction was improved by 2°, the TK increased by 4° and bone-screw force increased by about 25N (p < 0.05).

CONCLUSION

There was no significant difference in deformity corrections and bone-screw forces between the two techniques. Increasing differential contouring angle and rod diameter improved AVR and TK corrections with no significant effect on the MT Cobb angle. Although this study simplified the complexity of a generic surgical technique, the main effects of a limited number of identical steps were replicated for each case in a systematic manner to analyze the main first-order effects.

Genomic answers for children: Dynamic analyses of >1000 pediatric rare disease genomes

PURPOSE

This study aimed to provide comprehensive diagnostic and candidate analyses in a pediatric rare disease cohort through the Genomic Answers for Kids program.

METHODS

Extensive analyses of 960 families with suspected genetic disorders included short-read exome sequencing and short-read genome sequencing (srGS); PacBio HiFi long-read genome sequencing (HiFi-GS); variant calling for single nucleotide variants (SNV), structural variant (SV), and repeat variants; and machine-learning variant prioritization. Structured phenotypes, prioritized variants, and pedigrees were stored in PhenoTips database, with data sharing through controlled access the database of Genotypes and Phenotypes.

RESULTS

Diagnostic rates ranged from 11% in patients with prior negative genetic testing to 34.5% in naive patients. Incorporating SVs from genome sequencing added up to 13% of new diagnoses in previously unsolved cases. HiFi-GS yielded increased discovery rate with >4-fold more rare coding SVs compared with srGS. Variants and genes of unknown significance remain the most common finding (58% of nondiagnostic cases).

CONCLUSION

Computational prioritization is efficient for diagnostic SNVs. Thorough identification of non-SNVs remains challenging and is partly mitigated using HiFi-GS sequencing. Importantly, community research is supported by sharing real-time data to accelerate gene validation and by providing HiFi variant (SNV/SV) resources from >1000 human alleles to facilitate implementation of new sequencing platforms for rare disease diagnoses.

Diagnosis and Treatment of Idiopathic Congenital Clubfoot

Idiopathic congenital clubfoot is the most common serious musculoskeletal birth defect in the United States and the world. The natural history of the deformity is to persist into adult life with a significant decrease in function and quality of life. The Ponseti method (serial casting, Achilles tenotomy, and bracing of the clubfoot) has become the most effective and accepted treatment of children born with clubfoot worldwide. The treatment is successful, particularly when the Ponseti-trained practitioner (often a pediatric orthopedic surgeon), the primary care clinician, and the family work together to facilitate success. An important factor in the ultimate success of the Ponseti method is parental understanding of the bracing phase. There is a very high rate of recurrent deformity when bracing is not done properly or is stopped prematurely. The importance of positive education and support for the parents to complete the entire treatment protocol cannot be overstated. The goal of treatment is a deformity-free, functional, comfortable foot. Ponseti clubfoot programs have been launched in most countries throughout the world, including many countries with limited resources. Ultimately, the goal is that every infant born with a clubfoot will have access to care with the Ponseti method. This clinical report is intended for medical practitioners who are involved in the care of pediatric patients with clubfoot. Understanding the standard of care will help these practitioners to care for patients and their families.

Iliac screw instrumentation to the pelvis in children with neuromuscular and syndromic scoliosis. No lateral connectors and respect sagittal balance

STUDY DESIGN

One-center retrospective cohort study.

BACKGROUND

Compared to the traditional iliac screw technique, the modified iliac screw technique has a lower rate of distal implant failure in the treatment of neuromuscular scoliosis patients with pelvic obliquity. However, the reasons for decreased failure with the modified iliac screw technique are controversial.

QUESTIONS/PURPOSES

(1) Is distal implant failure, as evident by implant breakage or disconnection, more likely to occur in patients receiving the traditional iliac screw technique (PSIS) compared to the modified S2AI (MODS2) technique? (2) After controlling for relevant confounding variables, are there other identifiable risk factors for distal implant failure?

METHODS

We identified patients who underwent pelvic screw fixation by three pediatric spine surgeons from January 2007 to July 2017. Based on the starting point of the iliac screws, patients were divided into two groups. Group 1 consisted of PSIS fixation with an offset connector. Group 2 consisted of modified S2AI fixation without an offset connector. Demographic, operative, and radiographic data were obtained.

RESULTS

Cobb angle, lumbar lordosis, and pelvic obliquity were not significantly different between the two groups. Overall distal implant failure was 40/100 (40%) and significant between Group 1 PSIS 29/53 (55%) and Group 2 MODS2 11/47 (23%) (p = 0.002). No other complications were significant. Three risk factors were identified with implant failure: high pelvic incidence (17-fold increase, 95% confidence interval [CI] = 5.5 to 53.1, p < 0.001), high angle rod contour (3.8-fold increase, 95% CI = 1.2 to 11.9, p = 0.023), and use of an offset connector (3.2-fold increase, 95% CI = 1.0 to 10.3, p = 0.049). Failure did not correlate with the use of a cross-link, iliac screw diameter, or screw density. Revision surgery related to distal implant failure did not significantly differ between the two groups.

CONCLUSIONS

Compared to the use of an offset connector with PSIS fixation, MODS2 fixation had a lower rate of implant failure. Sagittal balance parameters, namely pelvic incidence and angle of rod bend, were the major risk factors for implant failure.

LEVEL OF EVIDENCE

III.

Anaphylaxis after injecting a hemostatic agent containing gelatin into vertebral bone under pressure-a warning

STUDY DESIGN

Case series.

PURPOSE

The use of topical hemostatic agents is common in spinal deformity surgery. While beneficial, emerging case data shows gelatin-containing agents causing intra-operative complications. We present two patients who developed anaphylaxis after injection of these gelatin-containing hemostatic agents into the vertebral body using manual pressure. In the literature, while anaphylactic reactions associated with the use of animal-derived gelatin has been implicated; the risk of injecting these products into the closed vascular cavity of the vertebral body with subsequent embolization into systemic circulation bears emphasis. This report is to meant to make the surgical team aware of the risks of injecting hemostatic agents using manual pressure into the vertebral body and to highlight a plausible mechanism for the phenomenon.

METHODS

Two children with spinal deformity undergoing posterior spinal fusion procedures with the use of gelatin-containing hemostatic agents injected into the vertebral body through the pedicle are described.

RESULTS

Both patients had gelatin-containing hemostatic agent solution injected under manual pressure through the vertebral pedicle to prevent excessive bleeding. Anaphylaxis occurred soon thereafter, resulting in emergent cessation of the surgery and initiation of medical resuscitation. In both cases, tryptase levels obtained just after the event were elevated.

CONCLUSION

Patients with an allergy to or prior history of exposure to zoologic products undergoing spine surgery may be at risk of anaphylaxis if the gelatin-containing hemostatic agent is injected under manual pressure into the closed space of the vertebral body. This allows rapid entry into the venous circulation. We recommend that the surgeon perform a thorough history of a patient's allergies and use extreme caution when injecting these topical hemostatic products into the vertebral body.

LEVEL OF EVIDENCE

IV.

Musculoskeletal Education: An Assessment of the Value of the American Academy of Pediatrics Musculoskeletal Boot Camp Course in Improving Clinical Confidence of Pediatricians Managing Common Musculoskeletal Conditions

In 2016, the American Academy of Pediatrics Section on Orthopaedics established an annual Musculoskeletal (MSK) Boot Camp course to fill the gaps in MSK knowledge, performance, and outcomes for pediatricians and primary care doctors. A standardized one-day curriculum of key MSK topics was developed including short lectures, hands-on workshops, debates, live webinars, and Q&A sessions. A survey was created to evaluate attendee confidence related to diagnosing 20 common MSK conditions in children and adolescents at the beginning and end of the course. Confidence in diagnosing the conditions was gauged using a 6-point Likert-type scale. A two-sample t test was used to compare overall confidence score pre- and post-seminar. In addition, each subtopic was analyzed. The average pre-seminar confidence score was 3.92 versus 4.86 post-seminar. All categories demonstrated a statistically increased confidence score post-seminar (P < .0001). Live MSK continuing education for pediatricians is effective in improving confidence in clinical practice.

Treatment of type III supracondylar humerus fractures: adherence and limitations of American Academy of Orthopedic Surgeons Appropriate Use Criteria App

The American Academy of Orthopedic Surgeons (AAOS) published Appropriate Use Criteria (AUC) in 2014 to aid physicians in the management of pediatric supracondylar humerus fractures. AUC should be evaluated in real practice, and if necessary modified based on identified problems. This study compares AAOS AUC recommendations with actual treatment performed in a cohort of patients treated for type III supracondylar humerus fractures. Medical record review of patients treated for type III supracondylar humerus fractures at our hospital from 2009 to 2016. Criteria required by the AAOS AUC were collected and entered into the AAOS AUC web-based application to determine the 'appropriateness' and score of each treatment. These were compared with the actual treatment the patient received. Over the study period, 585 patients (mean age: 6.5 years, 51% male, 49% female) were treated for type III supracondylar humerus fractures. Of the 585 cases, 561 (95.9%) were classified as 'appropriate', 24 (4.1%) as 'maybe appropriate', and 0 (0%) as 'rarely appropriate'. Of the 'maybe appropriate' cases there was a significant decrease in the proportion that deviated from the AUC over time (P = 0.0076). The main reasons for deviation were that an open reduction was performed due to difficulty with closed reduction (75% of deviations) or the surgery was not performed emergently (25% of deviations). The vague definition of 'emergent' and not allowing for open reduction if needed are limitations of the AUC that should be clarified or improved by the AAOS.

Twenty-two Years of Pediatric Musculoskeletal Firearm Injuries: Adverse Outcomes for the Very Young

BACKGROUND

Firearm injuries are a significant cause of morbidity and mortality for children in the United States. The purpose of this study is to investigate the 22-year experience of pediatric firearm-related musculoskeletal injuries at a major pediatric level 1 hospital and to analyze the risk of adverse outcomes in children under 10 years of age.

METHODS

An institutional review board-approved, retrospective cohort analysis was conducted on pediatric firearm-related musculoskeletal injuries at our institution from 1995 to 2017. A total of 189 children aged 0 to 18 years were identified using International Classification of Diseases, 9th Revision/10th Revision codes, focusing on musculoskeletal injuries by firearms. Exclusion criteria were primary treatment at an outside hospital, isolated nonmusculoskeletal injuries (eg, traumatic brain injury), and death before orthopaedic intervention. Two cohorts were included: age below 10 years and age 10 years and above. Primary outcome measure was a serious adverse outcome (death, growth disturbance, amputation, or impairment). Standard statistical analysis was used for demographic data, along with linear mixed models and multivariable logistic regression for adverse outcome.

RESULTS

Of the 189 children, 46 (24.3%) were below 10 years of age and 143 (75.7%) were 10 years and above. Fifty-two (27.5%) of the total group had an adverse outcome, with 19 (41.3%) aged below 10 years and 33 (23.1%) aged 10 years and above (P=0.016). Adverse outcomes were 3 deaths, 17 growth disturbances, 7 amputations, and 44 impairments. For those below 10 years of age, rural location (P=0.024), need for surgical treatment (P=0.041), femur injury (P=0.032), peripheral nerve injury (P=0.006), and number of surgeries (P=0.022) were associated with an adverse outcome.

CONCLUSIONS

Over one fourth of survivors of musculoskeletal firearm injuries had an adverse outcome. Children 10 years and above represent the majority of firearm injuries in our population; however, when injured, those below 10 years are more likely to have an adverse outcome.

LEVEL OF EVIDENCE

Level III.

The amount of surgical correction of the main thoracic curve is the best predictor of postoperative clinical shoulder balance in patients with Adolescent Idiopathic Scoliosis

PURPOSE

This study sought to analyze factors that predict postoperative shoulder balance based on clinical photography.

METHODS

Based on inclusion criteria, 132 AIS patients were selected. Age, sex, and BMI of each patient were recorded. The following parameters were recorded from radiographs: clavicle angle, T1 tilt, the upper instrumented vertebra (UIV), lowest instrumented vertebra (LIV) thoracic kyphosis, lumbar modifier, preoperative and postoperative proximal thoracic Cobb angle, preoperative and postoperative main thoracic Cobb angle, and preoperative and postoperative thoracolumbar Cobb angle, if applicable. Two spine surgeons independently assigned the photographs shoulder balance grades based on the WRVAS (1-2 = Acceptable, 3-5 = Unacceptable). Surgeons were blinded as to whether the photographs were taken preoperatively or postoperatively. The shoulders were also graded as right high, left high, or balanced.

RESULTS

Of all variables analyzed, only main thoracic Cobb angle correction (MTCAC) showed a statistically significant relationship with postoperative shoulder balance (p = 0.01). Odds of having unacceptable shoulder balance increase by 21% for every 5° increase in MTCAC (Adjusted OR = 1.21, 95% CI 1.015-1.452). The odds of unbalanced shoulders are 4.7 times higher for patients whose MTCAC is 40° or more (p = 0.001). Inter-rater reliability was excellent (k =0 .7). Intra rater reliability was perfect for Surgeon 1 (kappa = 1.0) and showed substantial agreement for Surgeon 2 (kappa = 0.8) CONCLUSIONS: Greater correction of main thoracic Cobb angle predicts unacceptable postoperative shoulder balance with 40° of correction signifying a major dichotomy between acceptable and unacceptable.

Continued vertebral body growth in patients with juvenile idiopathic scoliosis following vertebral body stapling

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To quantitatively measure the rate of growth of vertebral bodies in juvenile idiopathic scoliosis (JIS) treated with vertebral body stapling (VBS). VBS has been suggested to be a safe and effective method for modulating the growth of the young scoliotic spine, but few long-term studies have examined its efficacy.

METHODS

Seven patients with JIS 11 years of age or younger underwent VBS with a minimum 6-year follow-up. Vertebral body height on the unstapled and stapled aspects of the curve was measured from initial and final postoperative radiographs and converted into rate of growth per year. Known staple dimensions were used to standardize the measurements between radiographs. Interstaple distance was measured to demonstrate continued growth of the spine. Adjacent vertebral bodies without instrumentation served as an internal control of growth. Each vertebral body (n = 35) was analyzed as an individual experimental unit.

RESULTS

The average rate of growth was 0.86 mm/year (standard deviation [SD] 0.44, 95% confidence interval [CI] 0.71-1.0) per vertebral body on the stapled side and 0.83 mm/year (SD 0.46, 95% CI 0.67-0.98) per vertebral body on the unstapled side of the vertebral body. The adjacent vertebral body segments grew at a rate of 0.91 mm/year (SD 0.42, 95% CI 0.66-1.15) on the stapled side and 0.99 mm/year (SD 0.66, 95% CI 0.61-1.37) on the unstapled side, p < 0.01. The distance between staples increased significantly from 3.0 mm (SD 2.0, 95% CI 2.3-3.6) to 8.4 mm (SD 2.4, 95% CI 7.7-9.3).

CONCLUSIONS

Vertebral body growth in the presence of VBS occurred at a similar rate on the stapled and unstapled sides of the curve. The high standard deviation of instrumented segment growth further supports the conclusion that VBS is not a reliable method of growth modulation in the young scoliotic spine.

LEVEL OF EVIDENCE

IV.

Development of a Global Pediatric Orthopedic Outreach Program in Ecuador Through Project Perfect World: Past, Present, and Future Directions

Global health delivery is a complex initiative requiring dedicated personnel to achieve a successful program. To be most beneficial, global health delivery should focus on cultural competence, bidirectional education, and capacity building through direct and purposeful means. The authors present the expansion of their global health delivery program in Ecuador focusing on the evolution of the program from a medical mission trip to a multilayered program that helps foster engagement, education, and learning while helping children who might not otherwise have access to care, along with future directions and potential methods to decrease the need for such initiatives in Ecuador.

The Burden of Pediatric Musculoskeletal Diseases Worldwide

Global burden of disease (GBD) refers to the economic and human costs resulting from poor health. The disability-adjusted life year is a measure of life lost from premature death and life not lived at 100% health. Surgery has long been neglected in the distribution of resources for global health. Because of years of life lived with a disability and the large proportion of children in a population, pediatric musculoskeletal conditions early in life can contribute to the GBD. Fortunately, the World Health Organization has recently promoted essential surgical services through its Emergency and Essential Surgical Care Project and Global Initiative.

Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST): Development and Validation of a Prognostic Model in Untreated Adolescent Idiopathic Scoliosis Using the Simplified Skeletal Maturity System

STUDY DESIGN

Prognostic study and validation using prospective clinical trial data.

OBJECTIVE

To derive and validate a model predicting curve progression to ≥45° before skeletal maturity in untreated patients with adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

Studies have linked the natural history of AIS with characteristics such as sex, skeletal maturity, curve magnitude, and pattern. The Simplified Skeletal Maturity Scoring System may be of particular prognostic utility for the study of curve progression. The reliability of the system has been addressed; however, its value as a prognostic marker for the outcomes of AIS has not. The BrAIST trial followed a sample of untreated AIS patients from enrollment to skeletal maturity, providing a rare source of prospective data for prognostic modeling.

METHODS

The development sample included 115 untreated BrAIST participants. Logistic regression was used to predict curve progression to ≥45° (or surgery) before skeletal maturity. Predictors included the Cobb angle, age, sex, curve type, triradiate cartilage, and skeletal maturity stage (SMS). Internal and external validity was evaluated using jackknifed samples of the BrAIST data set and an independent cohort (n = 152). Indices of discrimination and calibration were estimated. A risk classification was created and the accuracy evaluated via the positive (PPV) and negative predictive values (NPV).

RESULTS

The final model included the SMS, Cobb angle, and curve type. The model demonstrated strong discrimination (c-statistics 0.89-0.91) and calibration in all data sets. The classification system resulted in PPVs of 0.71-0.72 and NPVs of 0.85-0.93.

CONCLUSIONS

This study provides the first rigorously validated model predicting a short-term outcome of untreated AIS. The resultant estimates can serve two important functions: 1) setting benchmarks for comparative effectiveness studies and 2) most importantly, providing clinicians and families with individual risk estimates to guide treatment decisions.

LEVEL OF EVIDENCE

Level 1, prognostic.

Pediatric Lawnmower Injuries and Strategies for Prevention: A Systematic Review

BACKGROUND

Lawnmower injuries remain a preventable cause of serious morbidity and even mortality in children. We aimed to characterize lawnmower injuries in children and to describe reported mechanisms through a review of the literature to better understand these injuries and their prevention.

METHODS

The Embase and MEDLINE databases were queried for studies pertaining to pediatric lawnmower injuries, along with manual searching of references of included studies and Google Scholar searches. Reviews and case reports were excluded. Studies relating to lawnmower injuries were broadly included to ensure capture of the relevant studies. Studies with both adult and pediatric data were included if pediatric data were granular and available for separate analysis.

RESULTS

Thirteen studies met inclusion criteria: 8 single-center series and 5 national database studies. Age of injury was bimodal with peak frequencies at ages 3 and 16 years. National studies estimated a mean of 11.2 injuries per 100,000 children, with 5% to 8% of patients hospitalized. Analysis of both single-center series and national database studies revealed 3 major mechanisms of injury: blade injuries, projectile injuries, and burn injuries. Blade injuries resulted in higher morbidity, with a greater need for operative management, amputation, and longer length of hospitalization. Similarly, rider mowers posed a greater injury risk than push mowers.

CONCLUSIONS

This systematic review of lawnmower injuries in children identified patterns and mechanisms of injuries across the literature that may serve to educate parents, policy-makers, and health-care providers as well as provide data to develop and improve prevention strategies.

Pediatric Lawn-Mower Injuries Presenting at a Level-I Trauma Center, 1995 to 2015: A Danger to Our Youngest Children

BACKGROUND

Unintentional injuries are the leading cause of morbidity and mortality among children 0 to 18 years of age in the U.S. An estimated 9,400 to 17,000 pediatric lawn-mower injuries occur each year. The aims of this study were to better define the epidemiology of lawn-mower injuries and to identify predictors of severe lawn-mower injuries to optimize public education and injury prevention.

METHODS

All patients 0 to 18 years of age who presented to Children's Mercy Hospital (CMH), Kansas City, Missouri, during the period of 1995 to 2015 after sustaining a lawn-mower injury were identified using International Classification of Diseases, 9th Revision (ICD-9) codes. Demographic information and data regarding primary outcome measures (death, amputation, need for prosthesis, Injury Severity Score [ISS]) and secondary outcome measures were collected. Bivariate and multivariate analyses were used to identify risk factors for severe lawn-mower injuries.

RESULTS

One hundred and fifty-seven patients were identified, with a bimodal age distribution peaking at 4 and 15 years of age. Seventy-five percent of the subjects were male. Sixty-six percent of the patients were admitted to the hospital, with a mean length of stay of 6 days. An average of 3 operations were performed. Nineteen percent of the patients lived in a nonmetro/rural location. Lower-extremity injuries were most prevalent, affecting 84% of the patients. Forty percent of the patients experienced at least 1 traumatic amputation. Thirteen percent of the patients required a prosthesis after the injury. The average ISS was 8. Significant predictors of a higher ISS included an age of 0 to 9 years, a riding lawn mower, a grandparent operator, and a nonmetro/rural location. Younger children were more likely to be injured from a riding lawn mower, be the passenger of the mower or a bystander, be injured with a grandparent operator, and live in a nonmetro/rural location. Younger children also had a higher ISS and amputation rate, longer LOS, and more surgical procedures.

CONCLUSIONS

Education to protect younger patients should target parent, grandparent, and older sibling operators. Education for the older, teenage group should include safe mowing techniques. Efforts should also target nonmetro/rural populations and grandparents, specifically highlighting the severe dangers of riding lawn mowers when young children are passengers or bystanders.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

How does differential rod contouring contribute to 3-dimensional correction and affect the bone-screw forces in adolescent idiopathic scoliosis instrumentation?

BACKGROUND

Differential rod contouring is used to achieve 3-dimensional correction in adolescent idiopathic scoliosis instrumentations. How vertebral rotation correction is correlated with the amount of differential rod contouring is still unknown; too aggressive differential rod contouring may increase the risk of bone-screw connection failure. The objective was to assess the 3-dimensional correction and bone-screw forces using various configurations of differential rod contouring.

METHODS

Computerized patient-specific biomechanical models of 10 AIS cases were used to simulate AIS instrumentations using various configurations of differential rod contouring. The tested concave/convex rod configurations were 5.5/5.5 and 6.0/5.5mm diameter Cobalt-chrome rods with contouring angles of 35°/15°, 55°/15°, 75°/15°, and 85°/15°, respectively. 3-dimensional corrections and bone-screw forces were computed and analyzed.

FINDINGS

Increasing the difference between the concave and convex rod contouring angles from 25° to 60°, the apical vertebral rotation correction increased from 35% (SD 17%) to 68% (SD 24%), the coronal plane correction changed from 76% (SD 10%) to 72% (SD 12%), the thoracic kyphosis creation from 27% (SD 60%) to 144% (SD 132%), and screw pullout forces from 94N (SD 68N) to 252N (SD 159N). Increasing the concave rod diameter to 6mm resulted in increased transverse and coronal plane corrections, higher thoracic kyphosis, and screw pullout forces.

INTERPRETATIONS

Increasing the concave rod contouring angle and diameter with respect to the convex rod improved the transverse plane correction but with significant increase of screw pullout forces and thoracic kyphosis. Rod contouring should be planned by also taking into account the 3-dimensional nature and stiffness of the curves and combined with osteotomy procedures, which remains to be studied.

Defining the Differences in Transverse Plane Trajectories for Thoracic Pedicle Screw Insertion: Anatomic Versus Medial

STUDY DESIGN

Comparing thoracic pedicle screw trajectories, screw lengths, and starting points by examining osteologic specimens.

OBJECTIVE

Describe a medial screw trajectory (MST) compared to a screw trajectory along the anatomic pedicle angle (APA) in terms of trajectory, screw length, and starting point.

SUMMARY OF BACKGROUND DATA

Although thoracic pedicle screw insertion is commonly used for posterior fusion and instrumentation, there is little data to quantify an MST that avoids the great vessels and allows for greater screw purchase.

METHODS

Thirty adult female skeleton thoracic vertebral columns from the University of New Mexico Maxwell Museum of Anthropology Osteology Collection were photographed from axial and right and left lateral views from T1 to T12. Axial plane measurements included APA and MST (both measured from the midline), screw lengths, and APA/MST intersection on the superior articular facet (SAF). The MST was defined as an insertion angle through the midpoint of the pedicle isthmus intersecting the anterior midpoint of the vertebral body. The intersection of each trajectory with the SAF was measured in relation to the lateral base of the SAF, reported as a percentage of the SAF base width from the lateral SAF border.

RESULTS

At every vertebral level, the APA was different from the MST for angle, screw length, and SAF intersection (p < .0001), with the largest difference at T12. The T12 differences were APA versus MST angles (-25.5°, 95% CI -22.7° to -28.4°), screw lengths (11.0 mm, 95% CI 9.2 mm to 12.9 mm), and percentage of SAF width from the lateral border of the SAF base (38.6%, 95% CI 29.1% to 48.1%).

CONCLUSIONS

The MST was approximately 8° to 10° greater at T1-T10 (19° at T11 and 25° at T12) than the traditional APA insertion angle. This resulted in a much more lateral starting point on the SAF and longer screw length, greatest at T12.

Patterns of Rib Growth in the Human Child

INTRODUCTION

Whereas there is substantial information on the changes of the rib cage during childhood and asymmetry of the thorax in children with scoliosis, there are virtually no normative data on the growth of individual ribs throughout childhood.

METHODS

The Hamann-Todd (HT) Osteological Collection provided the bones of 32 human specimens aged 1-18 years. A total of 6,226 individual photographs of all vertebral bodies and ribs were obtained from these specimens. Quantitative measurements were taken with image analysis software and the results of 2 of the measurements, the outer costal length (OCL) and the base diameter (BD), are presented here.

RESULTS

With the exception of the ribs at T12, both the OCL and BD showed linear, statistically significant growth with age for all ribs. The relationship of OCL and BD to each other within each rib was obtained by multiplying and dividing these 2 measurements. The BD × OCL product indicates that the ribs grow through coupled symmetry, by which ribs in the upper and lower thorax start at the same size and grow at the same rate within the pair; ribs 1 and 12, 2 and 11, and 3 and 10. Each rib pair grows at a significantly different rate from all other pairs. Measurements of BD and OCL from a specimen with scoliosis from the collection compared with these normative values were greatly different. The principle that ribs resemble a known geometric form, called the logarithmic spiral, is introduced.

CONCLUSIONS

This article is 1 of the first studies of the change in length and shape of normal ribs in an osteology collection of a wide age range of pediatric specimens. The data provide a framework for determining the difference between ribs from normal children and those with scoliosis.

Evaluation and treatment of developmental hip dysplasia in the newborn and infant

Developmental dysplasia of the hip (DDH) encompasses a spectrum of physical and imaging findings. The child's hip will not develop normally if it remains unstable and anatomically abnormal by walking age. Therefore, careful physical examination of all infants to diagnosis and treat significant DDH is critical to provide the best possible functional outcome. Regardless of the practice setting, all health professionals who care for newborns and infants should be trained to evaluate the infant hip for instability and to provide appropriate and early conservative treatment or referral.

Biomechanical analysis of iliac screw fixation in spinal deformity instrumentation

BACKGROUND

High rates of iliac screw fixation failures have been reported in spinopelvic instrumentations. The objective was to assess the iliac screw loads as functions of instrumentation variables.

METHODS

Spinopelvic instrumentations of six neuromuscular scoliosis were simulated using patient-specific modeling techniques to evaluate the intra- and postoperative iliac screw loads as functions of instrumentation variables: the combined use of sacral screws, the uses of lateral offset connectors and cross-rod connectors, and the iliac screw insertion point and trajectory.

FINDINGS

Sacral screws, lateral connectors and the iliac screw insertion point had significant effects on iliac screw axial forces (69-297N) and toggle moments (0.8-2.9Nm) (p<0.05). The addition of sacral screws made the iliac screw forces lower for some functional loads but higher for other functional loads, and resulted in an increase of intraoperative screw forces when attaching the rods onto these additional screws. When lateral offset connectors were used, the toggle moments were 16% and 25% higher, respectively for the left and right sides. Inserting iliac through the sacrum resulted in 17% lower toggle moment compared to insertion through the iliac crest. Cross-rod connectors had no significant effect on the intraoperative iliac screw forces. Postoperative functional loading had an important effect (additional 34% screw axial force and 18% toggle moment).

INTERPRETATION

It is possible to reduce the iliac screw loads by adapting instrumentation variables and strategies. Reducing the loads could decrease the risk of failure associated with iliac screw fixations.

Biomechanical analysis of forces sustained by iliac screws in spinal instrumentation for deformity treatment: preliminary results

Iliac screws used in long instrumentation for deformity treatment are subject to large forces, which may sometimes lead to fixation failures (intra- and postoperatively). The objective of this study was to analyze the biomechanics of iliac screw fixations. The study was based on a patient-specific simulation of a neuromuscular scoliosis case with a long instrumentation to the pelvis. A multi body flexible model was created using a preoperative 3D reconstructed spine and pelvis. The side bending radiographs were used to personalize the mechanical properties. The instrumentation construct was modeled as rigid bodies and flexible beams connected by kinematic joints. Three instrumentation parameters were studied: the connector length, the inter rod connectors and the use of sacral screws. The simulations showed that the forces and torques at the iliac screws were lowered by 9% and 25% respectively by reducing the lateral connector length (from 20 to 10 mm). An inter rod connector did not significantly reduce the iliac screw loads. Sacral screws reduced the functional loads on the iliac screws, but hardware related problems may be shifted onto the sacral screws. Sacral screws in conjunction with inter rod connectors reduced the loads at iliac screws without overloading the sacral screws. The preliminary results showed that the forces at the iliac screws could be lowered through different instrumentation parameters. In the next step of the study, the model validation will be further completed and used to evaluate other instrumentation factors by means of an experimental design framework. The knowledge of loading biomechanics at the iliac screw fixation is important for finding solutions to reduce the risk of failure, such as improving preoperative planning, instrumentation techniques and iliac screw construct design.

Prospective, surgeon-randomized evaluation of crossed pins versus lateral pins for unstable supracondylar humerus fractures in children

Controversy exists concerning pin placement for supracondylar humerus fractures in children. Both crossed pin and lateral only pin configurations have shown good results; however, prospective studies are lacking. We present a prospective, surgeon-randomized study comparing crossed pin (group A, n = 20) versus preferential lateral only pin (group B, n = 20) fixation for displaced supracondylar humerus fractures. There was no difference in Baumann's angle (P>0.75), the humerotrochlear angle (P>0.85), or final elbow range of motion (P>0.25). Both groups had stable reductions and clinically normal alignment. The only complication in both groups was a transient ulnar nerve irritation, despite no intraoperative evidence of nerve violation with a nerve stimulator. One patient in each group required modification of the operative plan. In group B, one patient had a medial pin inserted because of medial comminution extending proximally limiting available lateral pin placement. In group A, the surgeon elected to use lateral pins only because of an obviously subluxating ulnar nerve. In conclusion, we recommend orthopedic surgeons treating unstable pediatric supracondylar humerus fractures be facile with both medial and lateral pin placement.

Effect of cultural factors on outcome of Ponseti treatment of clubfeet in rural America

BACKGROUND

Nonoperative management of clubfoot with the Ponseti method has proven to be effective, and it is the accepted initial form of treatment. Although several studies have shown that problems with compliance with the brace protocol are principally responsible for recurrence, no distinction has been made with regard to whether the distance from the site of care affects the early recurrence rate. We compared early recurrence after Ponseti treatment between rural and urban ethnically diverse North American populations to analyze whether distance from the site of care affects compliance and whether certain patient demographic characteristics predict recurrence.

METHODS

One hundred consecutive infants with a total of 138 clubfeet treated with the Ponseti method were followed prospectively for at least two years from the beginning of treatment. Early recurrence, defined as the need for subsequent cast treatment or surgical treatment, and compliance, defined as strict adherence to the brace protocol described by Ponseti, were analyzed with respect to the distance from the site of care, age at presentation, number of casts needed for the initial correction, need for tenotomy, and family demographic variables.

RESULTS

Of eighteen infants from a rural area who had early recurrence, fourteen were Native American. The families of these children, like those of all of the children with early recurrence, discontinued orthotic use earlier than was recommended by the physician. Discontinuation of orthotic use was related to recurrence, with an odds ratio of 120 (p < 0.0001), in patients living in a rural area. Native American ethnicity, unmarried parents, public or no insurance, parental education at the high-school level or less, and a family income of less than $20,000 were also significant risk factors for recurrence in patients living in a rural area. Intrinsic factors of the clubfoot deformity were not correlated with recurrence or discontinuation of bracing.

CONCLUSIONS

Compliance with the orthotic regimen after cast treatment is imperative for the Ponseti method to succeed. The striking difference in outcome in rural Native American patients as compared with the outcomes in urban Native American patients and children of other ethnicities suggests particular problems in communicating to families in this subpopulation the importance of bracing to maintain correction. An examination of communication styles suggested that these communication failures may be culturally related.

Screening the newborn for developmental dysplasia of the hip: now what do we do?

The Pediatric Orthopaedic Society of North America recommends that all health care providers who are involved in the care of infants continue to follow the clinical practice guideline for early detection of developmental hip dysplasia (DDH) outlined by the American Academy of Pediatrics. Although evaluation of children with risk factors for DDH is important, most DDH occurs in infants who have no risk factors. For all infants, a competent newborn physical examination using the Ortolani maneuver is the most useful procedure to detect hip instability. Early treatment of an unstable hip with a Pavlik harness or similarly effective orthosis is effective, safe, and strongly advised. Despite having had normal newborn and infant hip examinations, there remains the possibility of a late-onset hip dislocation needing treatment in approximately 1 in 5000 infants.

Intraoperative visible bubbling of air may be the first sign of venous air embolism during posterior surgery for scoliosis

STUDY DESIGN

Case report of two children sustaining venous air embolism (VAE) during posterior surgery for scoliosis.

OBJECTIVES

To report 2 cases where visible bubbling at the operative site was the first clinical indication of VAE-induced cardiovascular collapse and to raise the level of consciousness that VAE in the prone position can occur, often with serious consequences.

SUMMARY OF BACKGROUND DATA

Twenty-two cases of VAE during surgery for scoliosis in the prone position have been reported. Ten were fatal and ten were in children. Visible bubbling at the operative site was noted in two published cases.

METHODS

Retrospective study of 2 cases of VAE at one institution. Clinical, anesthetic, and radiographic features are presented. Details of previously published cases are reviewed and discussed.

RESULTS

Both patients were girls with adolescent scoliosis who underwent prone positioned posterior spinal fusion with instrumentation. Visible bubbling of air at the thoracic aspect of the surgical site was noted near the completion of instrumentation and was the first indication of VAE. In both cases, this was clinically recognized and promptly treated. One patient survived normally and the other died.

CONCLUSIONS

Visible air bubbling at the operative site may herald the onset of massive VAE during multilevel posterior spinal fusion and instrumentation. A prospective multicenter study using precordial Doppler, central venous catheter, and end-tidal CO2 is recommended to determine the true incidence of VAE in spinal deformity surgery and to evaluate monitoring and treatment methods.

Management of pediatric femoral shaft fractures

Femoral shaft fractures are the most common major pediatric injuries managed by the orthopaedic surgeon. Management is influenced by associated injuries or multiple trauma, fracture personality, age, family issues, and cost. In addition, child abuse should be considered in a young child with a femoral fracture. Nonsurgical management, usually with early spica cast application, is preferred in younger children. Surgery is common for the school-age child and for patients with high-energy trauma. In the older child, traction followed by casting, external fixation, flexible intramedullary nails, and plate fixation have specific indications. The skeletally mature teenager is treated with rigid intramedullary fixation. Potential complications of treatment include shortening, angular and rotational deformity, delayed union, nonunion, compartment syndrome, overgrowth, infection, skin problems, and scarring. Risks of surgical management include refracture after external fixator or plate removal, osteonecrosis after rigid antegrade intramedullary nail fixation, and soft-tissue irritation caused by the ends of flexible nails.

Sports for the physically challenged child

Participation in sports is important for the physical and emotional health of the physically challenged child. Sports can improve strength, endurance, and cardiopulmonary fitness while providing companionship, a sense of achievement, and heightened self-esteem. With interest in such participation increasing, it is necessary for the physicians, therapists, and families of children with special needs to understand the preparticipation evaluation, athletic options, specialized equipment, and sport-specific risks. Recommendations that provide guidelines for safe, effective participation in sports are currently available for common congenital and developmental disabilities such as Down syndrome, cerebral palsy, myelodysplasia, hemophilia, congenital amputations, and arthritic disorders.

Cavus foot deformity in children

A cavus deformity of the foot is easily recognizable, but appropriate neurologic assessment can help to determine the etiology. Cavovarus, the most frequent type of cavus foot, presents with an elevated medial longitudinal arch, first ray plantarflexion, and, if rigid, a fixed heel varus. Common causes include progressive motor sensory conditions, typically Charcot-Marie-Tooth disease, and nonprogressive conditions such as cerebral palsy and poliomyelitis. A calcaneocavus foot may be seen in poliomyelitis, spinal dysraphism, and peripheral neuropathy. Initially, the cavus deformity is flexible, but if left untreated, it becomes a fixed bony deformity. Physical examination should include the cavovarus block test, which assesses flexibility of the hindfoot deformity and can direct surgical treatment. Standing radiographs of the feet and spine, magnetic resonance imaging, and electrodiagnostic studies may be useful. Management goals are to obtain a plantigrade, mobile, pain-free, stable, motor-balanced foot. Surgical options include soft-tissue and plantar fascia releases for a flexible deformity, osteotomy for a fixed deformity, and tendon transfers to restore muscle balance. Triple arthrodesis has poor long-term results in patients with progressive deformity and sensory impairment.

The pylon concept of pelvic anchorage for spinal instrumentation in the human cadaver

STUDY DESIGN

Human cadavera morphometric analysis of the iliac columns and biomechanical implant testing of traditional Galveston technique compared to intrailiac instrumentation of the entire iliac column.

OBJECTIVES

To describe the anatomy of the iliac columns and to evaluate the strength in forward flexion of a large implant spanning the entire column length compared to standard Galveston technique.

SUMMARY OF BACKGROUND DATA

We have observed substantial and straight columns of bone in the pelvis, connecting the acetabula to the sacrum, which may allow for improved spinopelvic instrumentation.

METHODS

Twenty adult cadaveric pelves were used. Each specimen was oriented in the computed tomography scanner to obtain a cross-section of the iliac columns, which begin from 2 cm caudal to the posterior iliac spines and end above the acetabula at the anterior inferior iliac spines. Two different instrumentation techniques were used. Standard Galveston pelvic fixation with paired 6.25-mm diameter rods extending 8 cm into the pelvis (Group 1) was compared to paired 8-mm diameter, 15-cm long custom implants, placed within the length of the entire iliac columns and connected to 6.25-mm spinal rods (Group 2). Both constructs had two rigid cross-links connecting the rods. Testing in forward flexion was performed for each construct with the MTS model 881 at 5 N/sec until failure occurred.

RESULTS

The rectangular shaped iliac columns averaged 15.2 (SD 0.8) cm in length, 2.5 (SD 0.3) cm in width and were consistently straight. The iliac column orientation as viewed in the transverse plane was 22 degrees laterally directed from the midsagittal plane. For the Galveston technique, failure with a flexion force occurred at a mean of 682 (SD 217) N. The iliac column implants failed at a mean of 2153 (SD 1370) N (P < 0.004).

CONCLUSION

The human adult pelvis has substantial and straight columns of bone extending from 2 cm below the posterior iliac spine, traversing above the sciatic notch, and ending at the anterior iliac spine. The shape resembles a weight-bearing long bone such as the tibia. Analogous to the architectural pylon, in this cadaver model, large implant instrumentation of the entire length of these pelvic columns provides at least three times stronger anchorage for spinal instrumentation compared to standard Galveston technique.

Factors affecting forearm compartment pressures in children with supracondylar fractures of the humerus

This study evaluated forearm compartment pressures in 29 children with supracondylar humerus fractures. Pressures were measured before and after reduction in the dorsal, superficial volar, and deep volar compartments at the proximal 1/6th and proximal 1/3rd forearm. Pressures in the deep volar compartment were significantly elevated compared with pressures in other compartments. There were also significantly higher pressures closer to the elbow within each compartment. Fracture reduction did not have a consistent immediate effect on pressures. The effect of elbow flexion on post-reduction pressures was also evaluated; flexion beyond 90 degrees produced significant pressure elevation. We conclude that forearm pressures after supracondylar fracture are greatest in the deep volar compartment and closer to the fracture site. Pressures greater than 30 mm Hg may exist without clinical evidence of compartment syndrome. To avoid unnecessary elevation of pressures, elbows should not be immobilized in >90 degrees of flexion after these injuries.

Predicting ulnar nerve location in pinning of supracondylar humerus fractures

Thirty-four consecutive patients with displaced supracondylar humerus fractures were treated with reduction and percutaneous pinning. The precise location of the ulnar nerve to the medial pin was determined by intraoperative nerve stimulation. In 22 of the 34 patients, the authors attempted to predict the location of the ulnar nerve by palpation and placing a mark on the skin. They also recorded the ability to feel the anatomic landmarks for pin fixation, including the medial epicondyle and ulnar nerve. The average distance from the medial pin to the predicted location was 9.3 mm, whereas the actual distance measured 7.6 mm, for a significant difference of 1.7 mm. Statistically, the authors could not accurately predict the location of the ulnar nerve prior to blind percutaneous crossed K-wire fixation of supracondylar humerus fractures. However, clinically they were fairly close in their prediction and documented safe insertion and distance from the nerve. Intraoperative nerve stimulation may assist in localizing the nerve prior to placement of the medial pin. Stimulation of the pin itself following insertion is another technique to ensure safe pin placement and decrease the risk of injury.

Accuracy of fluoroscopically assisted laser targeting of the cadaveric thoracic and lumbar spine to place transpedicular screws

A simple and inexpensive method was developed to obtain a coaxial view of the pedicles to assist with screw insertion. The authors evaluated the accuracy of this device to place transpedicular vertebral screws in a human adult cadaver model. A dual radiation targeting system, a laser targeting system for fluoroscopically guided procedures, was developed to provide an accurate surface entry point and angle of approach to radiographic landmarks. After fluoroscopic cross-hair target localization of the coaxial view of the pedicle, X-ray radiation is turned off and the laser beam allows the surgeon to guide the screw through the pedicle. Nine cadaver spines were removed and mounted. Three surgeons, inexperienced in the technique of pedicle screw placement, fitted instruments to 184 pedicles between L5 and T5. A total of 83 lumbar and 101 thoracic pedicles underwent screw placement. After specimen dissection, the degree and location of any screw perforation were measured by direct inspection. Three screws perforated a pedicle, for an error rate of 1.6%. Two lumbar screws (2.4% error) and one thoracic screw (1% error) perforated the pedicle. No screw was more than 1 mm outside the pedicle. Five other screws, four in the thoracic spine and one in the lumbar spine (error rate of 2.7%) were directed too far laterally and perforated the lateral vertebral body. This low rate of pedicle wall cortical perforation by inexperienced surgeons compares favorably with much higher pedicle perforation rates by experienced surgeons when no imaging was used. In conclusion, this in vitro model using a dual radiation targeting system assisted with the accurate placement of transpedicular vertebral screws with minimal radiation exposure.

Femur shaft fractures in toddlers and young children: rarely from child abuse

One hundred thirty-nine children younger than 4 years were identified retrospectively from the period of 1993 through 1997 to have an isolated fracture of the shaft of one or both femurs. Abuse was classified as group A (definite, likely, or questionable abuse) or group B (unknown cause, questionable accident, likely accident, or definite accident). The average age of the children was 2.3 +/- 1.1 years. Thirteen children, 9% of the total group, average age of 1.1 +/- 1.0 years, were likely to have been abused (group A). A total of 126 children, 91% of the total, average age 2.3 +/- 1.0 years, sustained their fracture most likely as a result of an accident (group B). Whether a child had not yet achieved walking age (toddler) was the strongest predictor of likely abuse. Ten (42%) of 24 of nonwalking children were in group A, whereas only three (2.6%) of 115 of walking children were in group A (p < 0.001). Child Protective Services may have been unnecessary in 42-63% of cases. Unless other evidence of abuse such as an inconsistent story, bruises, or other fractures are present, abuse is very unlikely to be involved in the walking-age child, analogous to the toddler fracture of the tibia.

Intraarticular knee ganglion: a case report of an unusual cause of limping in a 4-year-old

This report describes a 4-year-old boy who presented to the orthopaedic clinic with a primary complaint of limping and refusal to bear full weight on his right leg. An extensive evaluation revealed an intercruciate ganglion cyst of the knee. Diagnostic arthroscopy of the right knee was performed, and the cyst was aspirated and debrided. Magnetic resonance imaging of the knee 3 months and 1 year postoperatively showed a small remnant of the cyst adjacent to the posterior cruciate ligament. At the most recent clinical examination, 13 months postoperatively, the patient was symptom free. To the best of our knowledge, this is the youngest patient in the literature to be diagnosed with an intraarticular knee ganglion.

Untreated acetabular dysplasia of the hip in the Navajo. A 34 year case series followup

Patients born in the Many Farms District of the Navajo Indian Reservation from 1955 to 1961 were studied. Five hundred forty-eight of the 628 infants born (87%) received clinical examinations and pelvic radiographs at some time during the first 4 years of their lives. Eighteen (3.3%) of the 548 infants examined had acetabular dysplasia. Because of traditional cultural beliefs, none of these children received medical treatment. Followup evaluations and radiographs were obtained in these 18 patients during early adolescence. In 10 of the original 18 patients followup evaluations and radiographs were obtained at an average age of 35 years. None of the dysplastic hips progressed to frank dislocation. The mean center edge angle improved from 7 degrees when the patients were 1 year of age, to 29 degrees when the patients were 12 years of age, to 30 degrees when the patients were 35 years of age. Despite overall improvement of hip measurements with maturity, eight hips in five of the 10 patients who were in their fourth decade of life and who were available for examination, had radiographic evidence of residual abnormalities. The hips in patients with subluxation during infancy were less likely to be normal as adults. The results of this 34-year followup study of untreated developmental hip dysplasia showed marked radiographic improvement in all patients during childhood; however, subtle abnormalities persisted in the radiographs of 40% of the hips.

Outpatient pediatric orthopedics. Common and important conditions

Many common pediatric orthopedic conditions can be managed by the pediatrician who has a knowledge of the natural history of these conditions. An accurate diagnosis is necessary to provide proper treatment, give advice to patients, or make referrals to the proper specialist. The authors' find that in approximately 95% of cases, a specific diagnosis can be made and that 40% of patient referrals for orthopedic problems could have been managed by the primary care physician. This article discusses some of the more common pediatric orthopedic problems often encountered by primary care physicians.

Spinal deformity in myelodysplasia. Correction with posterior pedicle screw instrumentation

STUDY DESIGN

A retrospective review of transpedicular instrumentation used in a series of 24 patients with myelodysplastic spinal deformities and deficient posterior elements.

OBJECTIVE

To describe the usefulness and efficacy of these instruments in the treatment of complicated myelodysplastic spinal deformity.

METHODS

The mean preoperative scoliosis was 75.7 degrees (range, 39-130 degrees) in the 22 patients with scoliotic deformities; 4 patients with thoracic hyperkyphoses averaged 70.5 degrees (range, 46-90 degrees) and 10 patients with lumbar kyphoses averaged 80.5 degrees (range, 42-120 degrees). The instrumentation extended to the sacrum in 4 patients and the pelvis in 9; 10 patients also underwent anterior release and fusion and 7 underwent concomitant spinal cord detethering. At an average follow-up of 4.0 years (2.0-7.7 years; one patient died at 8 months), all patients have fused (with the exception of two lumbosacral pseudarthroses).

RESULTS

At last follow-up, deformity measured 32.1 degrees scoliosis (range, 6-85 degrees), 30.8 degrees thoracic kyphosis (range, 24-35 degrees), and 0.0 degree lumbar kyphosis (range, 35 degrees kyphosis to 29 degrees lordosis). Three patients lost some neurologic function after surgery; two recovered within 6 months and one has incomplete recovery. No ambulatory patient lost the ability to walk. Five patients required additional surgical procedures; in three cases, there was instrumentation breakage associated with pseudarthrosis or unfused spinal segments.

CONCLUSIONS

Pedicle screw instrumentation is uniquely suited to the deficient myelodysplastic spine. Compared with historical control subjects, these devices have proven capable of significant correction of both scoliotic and kyphotic deformities. This instrumentation appears particularly useful in preserving lumbar lordosis in all patients and may preserve more lumbar motion in ambulatory myelodysplasia patients.

Chronic physeal fractures in myelodysplasia: magnetic resonance analysis, histologic description, treatment, and outcome

Thirteen myelodysplastic children with 19 chronic physeal fractures were treated. All were treated with prolonged immobilization (average, 5.8 months; range, 3-18 months) in either braces or casts; four of the fractures required operative fixation to facilitate healing. All were healed at 4.8-years follow-up but, in four of the fractures, the growth plate closed prematurely. Three of the children underwent magnetic resonance imaging (MRI) of the injured physes, and one underwent physeal biopsy as part of her operative epiphysiodesis. Histologic analysis revealed three distinct zones of physeal pathoanatomy: a normal zone of proliferation; a thickened, disorganized zone of hypertrophy; and a vascularized zone of fibrous tissue adjacent to the metaphysis. On MRI, there was thickening of the physis and irregularity of the zone of provisional calcification. The physeal cartilage and the juxtametaphyseal fibrovascular tissue enhanced with gadolinium. These findings corroborate earlier mechanistic proposals for physeal injury in myelodysplasia: chronic stress or trauma to the poorly sensate limb produces micromotion at the zone of hypertrophy, yielding a widened, disorganized physis, and leading to fracture, displacement, and delayed union.

A prospective evaluation of idiopathic left thoracic scoliosis with magnetic resonance imaging

Twenty-nine consecutive patients with idiopathic left thoracic scoliosis were prospectively studied using magnetic resonance imaging (MRI). T1-weighted sagittal and axial images were obtained on all patients from the brainstem to the tip of the conus. Two patients (7%) had a syrinx on MRI. The remaining 27 patients had normal MRIs. The prevalence of brainstem and spinal cord anomalies was much less common than reported in previous retrospective reviews.

Childhood scoliosis: clinical indications for magnetic resonance imaging

We retrospectively reviewed the magnetic resonance imaging studies that had been made for ninety-five patients who had idiopathic scoliosis. We wished to determine if we could identify any criteria that should be met before these studies are performed. The study group included thirty-one male patients and sixty-four female patients. The average age at the time of the imaging study was thirteen years (range, one to twenty-eight years). The average curve was 41 degrees (range, 11 to 95 degrees). Fourteen patients were seen to have an intraspinal abnormality on the imaging study: twelve had a syrinx, one had a syrinx and an astrocytoma of the spinal cord, and one had dural ectasia. Five of the eight patients who were less than eleven years old and who had a left thoracic curve had an intraspinal abnormality on the imaging study, but this combination of factors did not indicate the need for operative intervention. Four of the intraspinal abnormalities in the fourteen patients necessitated neurosurgical intervention; if the criteria for obtaining the imaging study had been restricted to neck pain and headache--particularly with exertion--and neurological findings such as ataxia, weakness, and a cavus foot, these abnormalities would have been diagnosed.

Treatment of severe spondylolisthesis in children by reduction and L4-S4 posterior segmental hyperextension fixation

Twenty children with severe lumbosacral spondylolisthesis underwent reduction, posterolateral fusion, and posterior fixation with an L4 to S2, 3, and 4 sublaminar wired rectangular rod to lessen lumbosacral kyphosis, allow early ambulation, and maintain correction. All patients had a postural deformity, 10 had preoperative neurologic findings, and 8 had severe pain. The average percentage of slip improved from 76% preoperatively to 55% postoperatively, and the slip angle improved from 25 degrees to 5 degrees (p < 0.0001). All patients had solid fusion by 6 months and no progression at 43 month follow-up on the average. We conclude that this technique reliably provides partial reduction, solid fixation, and fusion for patients with severe spondylolisthesis while allowing early ambulation. As with any spondylolisthesis reduction technique, neurologic risk should limit this procedure to well-selected patients.