Age-Stratified Outcomes of Mehta Casting in Idiopathic Early-Onset Scoliosis: A Multicenter Review.

BACKGROUND: This study provides age-stratified outcomes of cast treatment for idiopathic early-onset scoliosis. METHODS: This is a multicenter, retrospective review of patients with idiopathic early-onset scoliosis treated with Mehta casting at 4 tertiary children's hospitals between 2001 and 2016. The inclusion criteria were idiopathic early-onset scoliosis and a minimum follow-up of 2 years after casting ended. The exclusion criteria were <2 casts, >3 casts at an outside facility, and a major curve of <20° pre-treatment. Subjects were grouped by age at first cast: <18 months, 18 to <24 months, 2 to <3 years, 3 to <4 years, and ≥4 years. RESULTS: There were 134 patients with a mean follow-up of 5.2 years (95% confidence interval [CI], 4.8 to 5.5 years) after casting. Prior to treatment, the major curve was not significantly different between the various age groups and was a mean of 50.4° (95% CI, 48.0° to 52.8° [range, 22° to 109°]). Of the <18-month group (n = 59), at the final follow-up at a mean of 7.4 years (95% CI, 6.8 to 8.1 years) of age, 75% had scoliosis of <15°, and 6.8% had undergone a surgical procedure or had a major curve of ≥50°. The results declined in the 18 to <24-month group (n = 30), with a major curve of <15° at the final follow-up at 8.5 years (95% CI, 7.3 to 9.7 years) of age in 33% (p < 0.001), and 17% having undergone a surgical procedure or had a major curve of ≥50°, with results nearly identical in the 2 to <3-year group (n = 21). The results continued to decline with increasing age; 23% of the 3 to <4-year group had a major curve of <15° at the final follow-up, and 31% had undergone a surgical procedure or had scoliosis of ≥50°. Of the ≥4-year group, just 9.1% had scoliosis of <15° (p < 0.0001 compared with the <18-month group), and 64% had undergone a surgical procedure or had scoliosis of ≥50°. CONCLUSIONS: Children who underwent casting prior to 18 months of age were more likely to have a major curve of <15° at a minimum 2-year follow-up after casting. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Factors Affecting Slip Progression After In Situ Screw Fixation of Stable Slipped Capital Femoral Epiphysis.

BACKGROUND: Slip progression after in situ fixation of slipped capital femoral epiphysis (SCFE) has been reported as occurring in up to 20% of patients. We review SCFE treated with in situ single screw fixation performed at 2 hospitals over a 15-year period to determine the factors associated with slip progression. METHODS: This case-control study reviews SCFE treated with in situ single cannulated screw fixation with minimum follow up of 1 year and full closure of the affected physis. Slip progression (failure) was defined as worsening of the Southwick slip angle of 10 or more degrees or revision surgery for symptomatic slip progression. Univariate and multivariate analyses were performed comparing success and failure groups for patient characteristics, screw type and position, and radiographic measurements. RESULTS: Ninety three patients with 108 slips met all criteria, with 15 hips (14%) classified as having slip progression (failure). All failures had 3 threads or fewer across the physis. Five hips had 2 threads across the physis, and 4 of the 5 were classified as failures. Lower modified Oxford bone scores were found in the failure group, though the difference was small (0.9, P=0.013). Failure was also associated with partially threaded screws (P=0.001). Failed hips were associated with lower initial Southwick angles (32.8 degrees) than successful hips (40.4 degrees) (P=0.047). In the stepwise model for multivariate regression, 4 factors were identified as significant, with lower initial number of threads (P<0.0001), mild initial Southwick category (P=0.0050), male sex (P=0.0061), and partially threaded screw type (P=0.0116) predicting failure. CONCLUSION: This study is the largest to date evaluating risk factors for slip progression after SCFE fixation, and the first to consider revision surgery for symptomatic slip progression. For stable SCFE, we demonstrate that 4 threads across the physis with a fully threaded screw of 6.5 mm diameter or greater was sufficient to avoid slip progression. We provide a risk stratification for progression of slip showing that in some cases 3 threads across the physis may be sufficient. LEVEL OF EVIDENCE: Level III-case-control study.

Growth-friendly Spinal Instrumentation in Marfan Syndrome Achieves Sustained Gains in Thoracic Height Amidst High Rates of Implant Failure.

BACKGROUND: There are few reports on the surgical management of early-onset scoliosis (EOS) associated with Marfan syndrome (MFS). Affected patients tend to have more rapid curve progression than those with idiopathic EOS, and their course is further complicated by medical comorbidities. As surgical techniques and implants for growing spines become more widely applied, this study seeks to better delineate the safety and efficacy of growth-friendly spinal instrumentation in treating this population. METHODS: A prospective registry of children treated for EOS was queried for MFS patients treated between 1996 and 2016. Forty-two patients underwent rib-based or spine-based growing instrumentation and were assessed on preoperative, surgical, and postoperative clinical and radiographic parameters including complications and reoperations. Subgroup analysis was performed based on spine-based versus rib-based fixation. RESULTS: Patients underwent their index surgery at a mean age of 5.5 years, when the major coronal curve and kyphosis measured 77 and 50 degrees, respectively. Over half were treated with traditional growing rods. Patients underwent 7.2 total surgical procedures-4.7 lengthening and 1.9 revision surgeries not including conversion to fusion-over a follow-up of 6.5 (±4.1) years. Radiographic correction was greatest at index surgery but maintained over time, with a final thoracic height measuring 23.8 cm. Patients experienced a mean of 2.6 complications over the course of the study period; however, a small group of 6 patients experienced ≥6 complications while over half of patients experienced 0 or 1. Implant failures represented 42% of all complications with infection and pulmonary complications following. CONCLUSIONS: This is the largest report on patients with EOS and MFS. All subtypes of growth-friendly constructs reduced curve progression in this cohort, but complications and reoperations were nearly universal; patients were particularly plagued by implant failure and migration. Further collaborations are needed to enhance understanding of optimal timing and fixation constructs for those with MFS and other connective tissue diseases.

What Is the Cost of a "Cast Holiday" in Treating Children With Early Onset Scoliosis (EOS) With Elongation Derotation Flexion (EDF, "Mehta") Casting?

INTRODUCTION: Serial casting of children with early onset scoliosis (EOS) is an established treatment option. A break from cast treatment often called a "cast holiday," (CH) is often allowed by some centers, particularly over the summer months. The impact of CHs on treatment duration or outcome has not been examined. METHODS: Institution review board approved retrospective review of children treated for EOS with elongation derotation flexion ("Mehta") casting at a children's hospital between 2001 and 2016 with a minimum of 2 years' follow-up. A CH was defined as a minimum of 4 weeks out of the cast, braced, or unbraced.The analysis was performed to determine the impact of a CH within the first 18 months of treatment. Separate analyses were performed for the entire cohort of children castedduring the study period, and then separately looking at idiopathic EOS in isolation. The impact of a CH was assessed in terms of the likelihood of achieving scoliosis <15 degrees at the final follow-up ("success"). Odds ratios were used to assess group differences between "success" ratios, and Student t tests assessed group differences for parametric data. RESULTS: Ninety children met inclusion and exclusion criteria, 31 of whom took a CH during the first 18 months of treatment (34%). This included 59 patients with idiopathic EOS (66%), 18 with syndromic EOS, 5 congenital, and 1 neuromuscular. There were no statistically significant differences between CH and no CH groups.Forty-four percent of the no CH group achieved scoliosis <15 degrees at final follow-up, as opposed to 13% of the CH group, an odds ratio of 5.3 for success without a CH. When limited to children with idiopathic EOS, 56% achieved success in the no CH, versus only 22% in the group that took a CH, an odds ratio of 4.4 for success with no CH. CONCLUSION: This study demonstrates that children treated for EOS with serial casting who take a CH within the first 18 months of treatment are less likely to achieve scoliosis <15 degrees than those who persist with treatment. LEVEL OF EVIDENCE: Level III.

Management of Early-Onset Scoliosis-From Mehta Casts to Magnetically Expandable Rods: State of the Art in 2019.

Early-onset scoliosis (EOS) encompasses a wide variety of challenging to treat spinal deformities occurring in children before 10 years of age. The Classification of Early-Onset Scoliosis (C-EOS) has emerged as a useful classification for both clinical and research purposes, as have similar classifications of surgery and complications in the EOS population. Approaches to both nonsurgical and surgical management of EOS have changed dramatically in recent years. There has been a resurgence of interest in nonsurgical management of EOS following several reports of success with serial Mehta cast treatment. Distraction-based surgical approaches, whether rib- or spine-based, remain the mainstay of surgical treatment. The introduction and widespread adoption of magnetically controlled growing rods (MCGR) has altered the need for repeat surgeries for lengthening in distraction based surgery. However, it remains unclear whether overall complication and unplanned revision surgery rates will be improved over historical traditional growing rods or rib-based distraction. Conversion of growth-friendly instrumentation to a final fusion remains a challenging procedure, with high rates of complications and revision surgeries.

Prevalence of Hip Dysplasia and Associated Conditions in Children Treated for Idiopathic Early-onset Scoliosis-Don't Just Look at the Spine.

BACKGROUND: Hip dysplasia, congenital muscular torticollis, plagiocephaly, and metatarsus adductus are known to be associated. The etiology of infantile idiopathic scoliosis and its association with the aforementioned conditions is unknown. This study reviews a series of infantile scoliosis patients to address this gap. METHODS: The medical records of all patients treated with casting for early-onset scoliosis (EOS) from 2001 to 2016 were retrospectively reviewed. Inclusion criteria were a diagnosis of idiopathic EOS and age below 4 years at the time of the first cast. Demographic information, comorbid conditions, and radiographic measurements including Cobb angle and acetabular index (AI) were collected. The first acceptable anteroposterior pelvis radiograph for each patient was measured. An AI≥30 degrees was defined as hip dysplasia. A measurement between 25 and 30 degrees was defined as a "hip at risk." RESULTS: Between 2001 and 2016, 142 patients were treated with casting. Eighty-one patients met the inclusion criteria. The mean age at the first cast was 19.3 (±7.5) months and the mean Cobb angle was 53.6 (±18.8) degrees. There was no significant correlation between Cobb angle and AI. Nine patients met radiographic criteria for hip dysplasia (11.1%), only 4 of whom had been previously diagnosed. Thirty-six patients (44.4%) met the criteria of having at least 1 hip "at risk" of hip dysplasia. Ten patients (12.3%) had been diagnosed with torticollis and 13 patients (16.0%) with plagiocephaly. Three patients (3.7%) had been diagnosed with metatarsus adductus or clubfoot. In total, 30.9% of patients (25/81) had at least one of the above comorbid conditions. CONCLUSIONS: In a large group of children treated for idiopathic EOS, we found a high prevalence of commonly associated conditions-hip dysplasia, torticollis, plagiocephaly, metatarsus adductus, and clubfoot. In 6.2% of our sample, a diagnosis of hip dysplasia was not made in a timely manner despite routine radiographic spine follow-up. With increasing subspecialization within pediatric orthopaedics, surgeons need to maintain vigilance in assessing the entire child. LEVEL OF EVIDENCE: Level IV.

Pediatric Patient-Reported Outcomes Measurement Information System is Equivalent to Scoliosis Research Society-22 in Assessing Health Status in Adolescent Idiopathic Scoliosis.

STUDY DESIGN: This was a correlational study. OBJECTIVE: Determine the range of pediatric Patient-Reported Outcomes Measurement Information System (PROMIS) scores for patients treated for adolescent idiopathic scoliosis (AIS) and assess correlation with Scoliosis Research Society-22 (SRS-22) domain scores. SUMMARY OF BACKGROUND DATA: Patient reported outcome (PRO) measures are important metrics for measuring health status in diverse patient populations. PROMIS is increasingly being used in orthopedic practice. Existing literature compares PROMIS measures favorably to legacy measures in numerous adult orthopedic conditions. This study sought to define the range of PROMIS mobility, pain interference, and peer relationships scores for adolescents treated for AIS. Furthermore, correlations between these domains and equivalent domains in the legacy PRO, SRS-22, were determined. METHODS: Pediatric PROMIS and SRS-22 were obtained at routine clinical visits for AIS at a tertiary care children's hospital from January 2017 to October 2017. Spearman correlations were performed to examine the associations between three pediatric PROMIS domains and the SRS-22 domains. Only patients who completed both PRO measures were included in the analyses. Radiographic measurements were performed at each visit assessing sagittal and coronal deformity and overall spinal balance. RESULTS: One hundred thirteen patients with a mean age of 14.4 (standard deviation [SD] = 2.1) years completed the assessments. The mean pediatric PROMIS domain scores included: mobility 50.9 (interquartile range [IQR] 36.2-65.6); pain interference 45.9 (IQR 28.9-62.9); peer relations 52.6 (IQR 38.3-64.9).PROMIS mobility was strongly correlated with SRS-22 function (r = 0.65; P < 0.001). PROMIS pain interference was strongly correlated with SRS-22 pain (r = 0.70; P < 0.001). PROMIS peer relations was moderately correlated with SRS-22 Mental Health (r = 0.41; P < 0.001) and self-image (r = 0.34; P < 0.001). CONCLUSION: In AIS patients pediatric PROMIS pain interference and mobility correlate strongly with SRS-22 pain and function domains, while PROMIS peer relationships demonstrates moderate correlations with SRS-22 mental health and self-image. LEVEL OF EVIDENCE: 2.

Minimum 5-Year Follow-up of Mehta Casting to Treat Idiopathic Early-Onset Scoliosis.

BACKGROUND: With the exception of Mehta's 2005 report on her experience treating early-onset scoliosis with serial casting, all subsequent studies have had limited follow-up. This current study sought to assess the results of serial casting at a minimum 5-year follow-up and to identify the predictors of the sustained resolution of scoliosis. METHODS: This study is a retrospective review of children treated for idiopathic early-onset scoliosis with serial casting at a children's hospital between 2001 and 2013 with a minimum 5-year follow-up. A Cobb angle of ≤15° and a decrease in the Cobb angle of >20° at the most recent follow-up were separately assessed. The differences between groups based on these criteria were tested with Student t tests with alpha = 0.05. RESULTS: Fifty-four children were treated during the study period; of these, 38 had at least 5 years of follow-up and comprised the study sample. The mean follow-up (and standard deviation) was 8 ± 2 years (range, 5 to 13 years). The mean patient age at the time of the first cast was 24 ± 15.1 months (range, 9 to 63 months), with a mean Cobb angle of 56.2° ± 20.1° (range, 22° to 109°). Forty-nine percent of children had scoliosis of ≤15° at the time of the most recent follow-up, and 73% of children were improved by at least 20°. Children with ≤15° scoliosis, compared with children with >15° scoliosis, had significantly lower initial Cobb angle (48.2° compared with 63.7°; p = 0.016), supine traction Cobb angle (22.5° compared with 33.2°; p = 0.048), first-in-cast Cobb angle (24.1° compared with 37.6°; p = 0.01), and first-in-cast rib-vertebral angle difference (12.8° compared with 26.2°; p < 0.01). Age at the time of the first cast, initial rib-vertebral angle difference, flexibility, and body mass index were not significantly different (p > 0.05) between the groups. Three children who initially achieved scoliosis of ≤15° after casting substantially relapsed. CONCLUSIONS: At a minimum follow-up of 5 years, the initial Cobb angle, first-cast Cobb angle, rib-vertebral angle difference, and traction Cobb angle were all predictive of sustained scoliosis of ≤15°. However, with continued growth, relapse of scoliosis was seen in 3 patients. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Optimization of Casting in Early-onset Scoliosis.

BACKGROUND: Early-onset scoliosis is a spine deformity that presents before the age of 3 years. When compared with age-matched controls, children with the condition are known to be at risk for significant morbidity and mortality. Although many works support the use of casting for this condition, the key technical factors to optimize the outcomes of casting are not clear. This work was designed to evaluate the role of frequency of radiographic imaging and over the shoulder straps in the outcomes of casting. METHODS: Two surgeons at 2 centers followed nearly identical protocols for applying casts for early-onset scoliosis. At center A, the surgeon hoped to improve outcomes by obtaining radiographs after each cast and by reinforcing the cast with shoulder straps. At center B, the surgeon did not use shoulder straps and limited radiographs to once every 6 months. Children were included if they were 3 years or below of age and had a curve of ≥50 degrees at the time of the first cast and had a minimum of 3 years of follow-up. Center was used as a variable in a multivariable regression that also included: age at first cast, initial curve magnitude, and presence of a syrinx or genetic syndrome with the outcome of curve resolution. RESULTS: There were 40 children at center A, 9 of whom experienced resolution of their scoliosis. There were 36 children at center B, and 11 demonstrated scoliosis resolution. At center A, 2 of 10 children with a syrinx or genetic syndrome demonstrated curve resolution while 7 of 30 without these comorbidities did. At center B 3 of 10 children with a syrinx or genetic syndrome had curve resolution while 8 of 26 children without these comorbidities did. CONCLUSIONS: The children in group A demonstrated results very similar to the children of group B. Thus, the extra burden of shoulder straps and frequent radiographs are unnecessary. LEVEL OF EVIDENCE: Level III.

The Epidemiology of Slipped Capital Femoral Epiphysis in American Samoa.

The Maori of New Zealand have been identified as a high-risk population for slipped capital femoral epiphysis (SCFE). This study assessed whether the burden of disease from SCFE in the American Territory of American Samoa is similar to that identified in the Maori. This was a retrospective review of children from American Samoa treated for SCFE at a tertiary care pediatric hospital between 2005-2014. Demographic, clinical, and radiographic information was collected. All patients were followed for at least one year after surgery and prophylactically pinned hips were not included. Data for determining incidence was obtained from the United States Census Bureau. Between 2005-2014, 55 American Samoan youth were treated for 73 SCFE. The incidence in the "at-risk" population 5-14 years of age was 53.1 per 100,000. Patients had a mean BMI of 29.5 (19.4-46.4) and mean weight of 76.7 kg (45.9-139 kg). Southwick angle was a mean 40.6°+/- 20.4° (6-83°). Overall, 82.2% of hips were treated with in-situ cannulated screw fixation. At a minimum one-year after initial surgery, 22 hips (30.1%) required major surgery including intertrochanteric osteotomy, osteochondroplasty, or total hip replacement. The incidence of SCFE in American Samoa is extremely high, 53.1 per 100,000 of "at-risk" population 5-14 years old. The mean weight and BMI in SCFE patients from American Samoa is substantially higher than previously published reports. Furthermore, morbidity from SCFE in this population is substantial with 30.1% requiring major surgery either at the time of physeal stabilization or in subsequent years.

Use of Halo-Gravity Traction and a Magnetically Controlled Growing Rod for Untreated Severe Kyphoscoliosis in an Adolescent: A Case Report.

CASE: We utilized a novel staged approach for an adolescent with severe kyphoscoliosis; it involved 8 weeks of initial halo-gravity traction as well as implantation and expansion (every 2 weeks) of a magnetically controlled growing rod over 6 months, followed by spinal fusion. The patient was a 13-year-old girl with an untreated idiopathic deformity (thoracic scoliosis with a curve of 145° and kyphosis with a curve of 120°). No osteotomies other than inferior facetectomies were required at the final fusion, and the final scoliosis curve was 57°, a correction of 60.7%. CONCLUSION: The staged approach resulted in a straightforward, safe, gradual correction of severe kyphoscoliosis. We consider this an option for patients with scoliosis with a curve of ≥130° on initial presentation.

Surgeon Experience Does Not Change Rate of Perioperative Surgical Complication in Rib-Based Distraction Surgery for Early-Onset Scoliosis.

OBJECTIVE: To report on the surgical learning curve in treating early-onset scoliosis with rib-based distraction. SUMMARY OF BACKGROUND DATA: The idea of a surgical learning curve proposes improved outcomes with experience. Early-onset scoliosis (EOS) is a challenging condition to treat and complication rates are high. METHODS: All patients from a single experienced spine surgeon's practice who had undergone placement of rib-based distraction constructs between 2002 and 2013 were identified. A retrospective chart review was performed to determine patient characteristics at implantation and follow-up surgeries and complications. The primary outcome was complication rate per surgical encounter. Experience was analyzed both by number of surgical procedures and year in study period. RESULTS: The surgeon began using rib-based distraction in 2002, and between 2002 and 2013, a total of 101 patients underwent 1,009 implantation or expansion surgeries involving rib-based distraction at a median age of 6 years at implantation (10 months-9.4 years). The median preoperative Cobb angle was 67° (8°-125°; IQR: 57°-76°) and follow-up was a median of 4.4 years (IQR 3.7-5.6 years). Overall, 65.3% of patients experienced complications, including 40 Grade I, 20 Grade II, 126 Grade IIA, and 3 Grade III. Univariate analysis identified a trend toward cumulative number of surgeries relating to a decreased complication rate, with every 50 surgeries decreasing the complication rate by 3% (p = .071). However, multivariate analysis found cumulative number of surgeries and complication rate to not be significantly related (p = .12). Surgeon experience as measured by study time (as both a continuous and categorical predictor) did not achieve statistical significance in either the univariate or multivariate models. CONCLUSION: This is the largest single-surgeon series of EOS patients treated with rib-based distraction. Surgeon experience defined either as number of procedures or years of experience within the study period did not impact the rate of complications.

Parallel Proximal Fixation in Rib-Based Growing Rod System: A Novel Approach to Deal With Proximal Anchor Migration.

STUDY DESIGN: Retrospective case control. OBJECTIVE: To report on differences in implant failure rates and complications requiring reoperation in children with early-onset scoliosis (EOS) treated with rib-based distraction utilizing four proximal fixation points in either a parallel or in-line configuration. SUMMARY OF BACKGROUND DATA: Proximal anchor failure continues to be a significant problem in growth-friendly surgery using rib-based distraction to treat children with EOS. Differences between parallel and in-line proximal anchor constructs have not been previously assessed. METHODS: A multicenter registry was reviewed to identify children treated for EOS with rib-based distraction between 2011 and 2014 with a minimum of 2 years follow-up after implantation. Patients were divided into those with in-line and parallel proximal rib-cradle configurations, and only those with exactly four fixation points (two per side) were included. Charts were reviewed for demographic, clinical, and radiographic information. RESULTS: A total of 56 patients were identified-31 with in-line constructs and 25 with parallel constructs. Follow-up in the in-line group was a mean of 4.06 years versus 3.16 in the parallel group (P = 0.001). Controlling for the different lengths of follow-up in the two groups there was a significantly higher rate of implant failure (P = 0.043) and requirement for nonroutine surgical intervention (P = 0.029) in the in-line group. There was a trend toward increased complications in the in-line group (P = 0.058). CONCLUSION: Failure of proximal fixation is the most common complication in management of EOS with rib-based distraction. This study identifies that when the number of proximal fixation points are matched, parallel constructs result in lower rates of implant failure and need for unplanned reoperation than in-line constructs. Although this study was limited to patients in whom the VEPTR device was employed, these principles are likely applicable to other rib-based distraction devices used to treat EOS. LEVEL OF EVIDENCE: 3.

Management of Terminal Osseous Overgrowth of the Humerus With Simple Resection and Osteocartilaginous Grafts.

BACKGROUND: Osseous overgrowth is a common complication in children after humeral transcortical amputation. Capping tibial overgrowth with the proximal fibula has been shown to be the most effective treatment. However, best treatment practices are not clear for the humerus. We compared patients treated surgically for humeral osseous overgrowth with simple resection or autologous osteocartilaginous graft to determine if this treatment were as effective in the humerus as it has been in the tibia. METHODS: A retrospective review of humeral amputees from 1987 to 2011 at a pediatric hospital was performed. Patients with 2 years follow-up who underwent surgical treatment for established humeral overgrowth were included. Patients initially managed with simple resection were compared with those managed with autologous osteocartilaginous grafts. Descriptive statistics were calculated for demographic and outcome variables. T tests and χ tests were used to compare differences between groups. RESULTS: Eighteen humeri in 16 patients met inclusion criteria. Mean age at surgery was 8.3 (2.6 to 13.6) years and mean follow-up was 6.3 (1.5 to 10.4) years. Thirteen humeri underwent simple resection, with recurrent overgrowth in 9, and revision surgery in 8 at a mean 2.6 years. Five humeri were primarily managed with autologous osteocartilaginous grafts. Two developed non-overgrowth-related complications at 1 and 42 months. Including revision procedures after simple resection, 10 humeri were managed with autologous osteocartilaginous grafts. Thirty percent (3/10) required revision surgery; however, there were no cases of recurrent overgrowth. χ comparison showed lower rates of complications (P=0.004) and reoperation (P=0.012) with capping as compared with simple resection. CONCLUSIONS: Autologous osteocartilaginous capping of the humerus has a significantly lower rate of complications and reoperation compared with simple resection. However, the capping procedure has the potential for other complications related to difficulty with graft fixation. Surgeons should be aware that the outcomes are not as consistent as when the technique is applied to osseous overgrowth of the tibia and anticipate the possibilities of hardware prominence and difficulty with fixation. LEVEL OF EVIDENCE: Level 3-therapeutic-retrospective comparative.

A Practical Approach to Determining the Center of the Femoral Head in Subluxated and Dislocated Hips.

BACKGROUND: Mistaking the ossific nucleus as the surrogate for the center of the femoral head affects treatment decisions in hip dysplasia. Previous studies of ossific nucleus position within the femoral head have been qualitative, or, have not included both subluxated and dislocated hips. The purpose of this study was, first, to determine the most accurate radiographic landmark to define the center of the immature femoral head in hip dysplasia, and, second, to quantitatively analyze the position of the ossific nucleus relative to the center of the femoral head. METHODS: The center of the femoral head was determined from hip arthrograms for 19 consecutive patients with untreated hip dysplasia. Three radiographic proxies for the center were defined on each film: (1) the center of the proximal physis; (2) the center of the ossific nucleus; and (3) a modification of Mose's concentric circles. Each point was compared with the true center of the head on an arthrogram. RESULTS: Nineteen patients of an average age of 35.5 months (range, 9 to 76 mo) yielded 22 dysplastic hips. Modified Mose circle was the most accurate technique. In subluxated hips, the center of the femoral physis was equally accurate. The ossific nucleus was the poorest estimation of the center of the femoral head. All of the ossific nuclei were located cephalad and lateral to the center of the femoral head as determined on arthrogram. CONCLUSIONS: The modified Mose technique is the most accurate technique for determining the center of the femoral head. In subluxated hips, the center of the physis is a practical, equivalent, technique. The ossific nucleus is a poor proxy for the center of the head in hip dysplasia. CLINICAL RELEVANCE: A modification of Mose's technique is the most accurate assessment of the center of the femoral head in both subluxated and dislocated hips. The center of the physis is a practical, reliable, surrogate for the center of the head in subluxated hips without requiring an arthrogram.

Osteocartilaginous transfer of the proximal part of the fibula for osseous overgrowth in children with congenital or acquired tibial amputation: surgical technique and results.

BACKGROUND: Osseous overgrowth is a common problem in children after tibial transcortical amputation. We present the results of forty-seven children (fifty tibiae) treated for tibial osseous overgrowth with an autologous osteocartilaginous cap from the proximal part of the ipsilateral fibula. METHODS: We reviewed the records of all patients who underwent amputation at a single pediatric hospital from 1990 to 2011. All patients who had been followed for a minimum of two years after undergoing osteocartilaginous capping with the proximal part of the ipsilateral fibula to treat established tibial overgrowth were included. Patients with acquired and congenital amputations were compared. RESULTS: Fifty tibiae in forty-seven patients met our inclusion criteria. There were thirty-one acquired and nineteen congenital amputations. The mean age at surgery was 7.6 years (range, 2.1 to 15.6 years), and the mean duration of follow-up was 7.2 years (range, 2.2 to 15.4 years). Five tibiae (10%) in four patients had recurrence of the overgrowth at a mean of 5.4 years (range, 2.8 to 7.6 years) after the osteocartilaginous transfer. There was no significant difference in the results between children with an acquired amputation and those with a congenital amputation. CONCLUSIONS: At a mean of 7.2 years after autologous osteocartilaginous capping with the proximal part of the fibula, 90% of the limbs had not had recurrent overgrowth. This is a safe and effective treatment of long-bone overgrowth following either congenital or acquired amputation in children.

Does pediatric body mass index affect surgical outcomes of lower-extremity external fixation?

BACKGROUND: Obese patients are highly prevalent in the pediatric orthopaedic surgeon's practice and obesity is an increasing issue in the United States. Increased body mass index (BMI) has been associated with increased complications in pediatric orthopaedic patients, but no study has looked specifically at external fixation. The purpose of this study was to determine whether obesity is a risk factor for increased complications in lower-extremity procedures requiring external fixation. METHODS: A retrospective chart review was conducted of pediatric patients who underwent external fixation as definitive operative treatment for any condition at a tertiary care hospital over a 15-year period. Patients were grouped into normal weight, overweight, and obese based on Centers for Disease Control definitions. All orthopaedic complications were recorded. RESULTS: A total of 208 patients with a mean age of 11.2 years were identified. Ninety-four children were obese at the 95th percentile BMI or higher, 22 were overweight and 93 were normal weight. External fixation was applied to the tibia in 82 cases, to the femur in 77 and to both in 49. Mean duration of fixation was 160 days (range, 31 to 570 d) and patients were followed for a mean of 3.9 years (range, 1.0 to 12.0 y). There was no statistically significant difference in the rate of complications between the 3 groups (P=0.61). In the obese group complications occurred in 68.1% versus 66.7% in the overweight group and 61.3% in normal weight. CONCLUSIONS: In the setting of external fixator use for lower-extremity pathology in pediatric patients, there is no association between an increase in complications and obesity as defined by BMI. Complication rates are high when external fixation is utilized for the lower extremity, however, patients and families should not be counseled that increased BMI will add to the burden of orthopaedic complications in this situation. LEVEL OF EVIDENCE: Level II-prognostic.