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.

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.

Intrawound Vancomycin Powder Associated With Reduced Surgical Site Infection in Rib-based Distraction Surgery.

BACKGROUND: Despite clinical reports of improved pulmonary function and reduced spinal deformity with rib-based distraction surgery in early-onset scoliosis (EOS) patients, infection remains a common complication, reported as high as 32% in some studies. The purpose of this study was to evaluate intrawound vancomycin powder in pediatric patients managed with rib-based distraction for EOS. METHODS: This was a single institution retrospective cohort study of EOS patients treated with rib-based distraction. Patients treated with and without intrawound vancomycin were compared. Patients included were younger than 18 years of age, had undergone placement of a rib-based distraction construct, and had a minimum of 6 months' follow-up. For patients in the vancomycin group, 500 mg of vancomycin powder was placed before wound closure. Complications including infection and revision surgery were recorded. P-values and 95% confidence intervals (CIs) were reported for both unadjusted and adjusted complication rates for prevancomycin and postvancomycin powder. All P-values were calculated at a significance level of 0.05. RESULTS: In total, 118 patients were included, accounting for 1035 procedures in the nonvancomycin control group and 252 procedures in the vancomycin group. Both groups were similar with regard to age at initial implant, sex, diagnosis, ambulatory status, and bowel/bladder incontinence. There were 55 (5.3%; 95% CI, 4.1-7.6) postoperative infections in the control group and 3 (1.2%; 95% CI, 0.3-3.8) in the vancomycin group (P=0.008, unadjusted). After adjusting for surgery type and transfusions, the vancomycin group still had a significantly lower infection rate (1.4%; 95% CI, 0.3-3.7 vs. 5.5%; 95% CI, 3.04-6.5; P=0.022). We were unable to demonstrate a difference between the control (3.5%, 95% CI, 2.4-5.1) and vancomycin (1.8%, 95% CI, 0.5-5.7) groups for deep infection (P=0.27). CONCLUSIONS: Intrawound vancomycin powder significantly reduced the surgical site infection rates following rib-based distraction surgery for EOS. We therefore recommend the use of intrawound vancomycin powder as a standard of care for patients undergoing rib-based distraction surgery. LEVEL OF EVIDENCE: Pre-post intervention, retrospective cohort study-therapeutic level III.

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.

Variation in Adolescent Idiopathic Scoliosis Surgery: Implications for Improving Healthcare Value.

OBJECTIVES: To investigate the variation in care and cost of spinal fusion for adolescent idiopathic scoliosis (AIS), and to identify opportunities for improving healthcare value. STUDY DESIGN: Retrospective cohort study from the Pediatric Health Information Systems database, including children 11-18 years of age with AIS who underwent spinal fusion surgery between 2004 and 2015. Multivariable regression was used to evaluate the relationships between hospital cost, patient outcomes, and resource use. RESULTS: There were 16 992 cases of AIS surgery identified. There was marked variation across hospitals in rates of intensive care unit admission (0.5%-99.2%), blood transfusions (0%-100%), surgical complications (1.8%-32.3%), and total hospital costs ($31 278-$90 379). Hospital cost was 32% higher at hospitals that most frequently admitted patients to the intensive care unit (P = .009), and 8% higher for each additional 25 operative cases per hospital (P = .003). Hospital duration of stay was shorter for patients admitted to hospitals with highest intensive care unit admission rates and higher surgical volumes. There was no association between cost and duration of stay, 30-day readmission, or surgical complications. The largest contribution to hospital charges was supplies (55%). Review of a single hospital's detailed cost accounting system also found supplies to be the greatest single contributor to cost, the majority of which were for spinal implants, accounting for 39% of total hospital costs. CONCLUSIONS: The greatest contribution to AIS surgery cost was supplies, the majority of which is likely attributed to spinal implant costs. Opportunities for improving healthcare value should focus on controlling costs of spinal instrumentation, and improving quality of care with standardized treatment protocols.

Guided growth for tibia vara (Blount's disease).

Blount's disease is commonly attributed to an intrinsic, idiopathic defect in the posteromedial proximal tibial physis resulting in progressive bowing of the leg, intoeing, and lateral knee thrust. Treatment has historically included bracing, physeal stapling, or corrective osteotomy, and was determined primarily by age at presentation. As we feel the pathology is not necessarily age dependent, we have elected to use the technique of guided growth using a lateral tension band plate to correct limb alignment as a first-line treatment in all patients presenting to our clinic as long as they had growth remaining and no evidence of a physeal bar.We identified 17 patients with tibia vara (27 limbs) who were managed by means of guided growth of the proximal tibia, from age 1.8 years to 15.1 years. Clinical and radiographic parameters were followed pre- and postoperatively. The response to guided growth was documented as were any related complications.Twenty-one (78%) limbs had complete normalization of their mechanical axis (middle 50% of knee). Time to correction averaged 13.5 months (8-19 months). There were no peri-operative complications. We observed hardware failure in 3 patients; 2 with screw breakage and 1 patient with hardware migration, none requiring subsequent osteotomy or further treatment. Two patients had rebound varus: one is being observed and another has undergone a repeat procedure.Patients with pathologic tibia vara present at various ages and have historically undergone various treatments ranging from bracing to tibial osteotomy based on age at presentation. We have found that guided growth utilizing tethering plates can be used effectively as first-line treatment in all patients with growth remaining. This minimally invasive method is predictable and well tolerated. Recurrent deformity, though unlikely, is easily remedied by repeating the process and does not preclude osteotomy if eventually needed. Concomitant resolution of ligamentous laxity and inward torsion can be anticipated as the mechanical axis is restored to neutral. The only contraindications for guided growth include an unresectable physeal bar or skeletal maturity.

Reliability analysis of Cobb angle measurements of congenital scoliosis using X-ray and 3D-CT images.

PURPOSE: Therapeutic decisions for congenital scoliosis rely on Cobb angle measurements on consecutive radiographs. There have been no studies documenting the variability of measuring the Cobb angle using 3D-CT images in children with congenital scoliosis. The purpose of this study was to compare the reliability and measurement errors using X-ray images and those utilizing 3D-CT images. MATERIALS AND METHODS: The X-ray and 3D-CT images of 20 patients diagnosed with congenital scoliosis were used to assess the reliability of the digital 3D-CT images for the measurement of the Cobb angle. Thirteen observers performed the measurements, and each image was analyzed by each observer twice with a minimum interval of 1 week between measurements. The analysis of intraobserver variation was expressed as the mean absolute difference (MAD) and standard deviation (SD) between measurements and the intraclass correlation coefficient (IaCC) of the measurements. In addition, the interobserver variation was expressed as the MAD and interclass correlation coefficient (IeCC). RESULTS: The average MAD and SD was 4.5° and 3.2° by the X-ray method and 3.7° and 2.6° by the 3D-CT method. The intraobserver and interobserver intraclass ICCs were excellent in both methods (X-ray: IaCC 0.835-0.994 IeCC 0.847, 3D-CT: IaCC 0.819-0.996 IeCC 0.893). There was no significant MAD difference between X-ray and 3D-CT images in measuring each type of congenital scoliosis by each observer. CONCLUSIONS: Results of Cobb angle measurements in patients with congenital scoliosis using X-ray images in the frontal plane could be reproduced with almost the same measurement variance (3°-4° measurement error) using 3D-CT images. This suggests that X-ray images are clinically useful for assessing any type of congenital scoliosis about measuring the Cobb angle alone. However, since 3D-CT can provide more detailed images of the anterior and posterior components of malformed vertebrae, the volume of information that can be obtained by evaluating them has contributed greatly to the development of strategies for the surgical treatment of congenital scoliosis.

Rib-based Distraction Surgery Maintains Total Spine Growth.

BACKGROUND: For children undergoing treatment of early onset scoliosis (EOS) using spine-based distraction, recently published research would suggest that total spine length (T1-S1) achieved after the initial lengthening procedure decreases with each subsequent lengthening. Our purpose was to evaluate the effect of rib-based distraction on spine growth in children with EOS. METHODS: This was a retrospective multi-center review of 35 patients treated with rib-based distraction (minimum 5 y follow-up). Radiographs were analyzed at initial implantation and just before each subsequent lengthening. The primary outcome was T1-S1 height, which was also analyzed as: Change in T1-S1 height per lengthening procedure, percent of expected age-based T1-S1 growth per lengthening time interval, percent increase in T1-S1 height as compared with postimplantation total spine height, and percent of expected T1-S1 growth based upon patient age at time of lengthening procedure. RESULTS: Thirty-five patients with a mean age of 2.6 years at initial surgery were studied. Diagnoses included congenital (n=18), syndromic (n=7), idiopathic (n=5), and neuromuscular (n=5). Major Cobb angle was 63.5 degrees and kyphosis was 40.5 degree. Four postoperative time periods were compared: L1 (preoperative first lengthening surgery), L2-L5 (preoperative second lengthening to preoperative fifth lengthening), L6-L10 (preoperative sixth lengthening to preoperative 10th lengthening), L11-L15 (preoperative 11th lengthening to preoperative 15th lengthening). Cobb angle stayed relatively constant for each lengthening period while maximum kyphosis increased. Total spine height was 19.9 cm pre-implantation, 22.1 cm postimplantation, and 28.0 cm by the 15th lengthening (P<0.05). Percent expected T1-S1 growth per lengthening was 62% for L2-L5, 95% for L6-L10, and 52% for L11-L15. As compared with postimplantation spine height, over the course of 15 lengthening procedures, a further 27% increase in spine height was observed. When lengthening procedures were performed when children were under age 5 years, 82% of expected growth was observed; between ages 6 and 10 years, 76% of expected growth was observed; and beyond age 10 years, 14% of expected growth was observed. CONCLUSIONS: Patients treated with rib-based distraction surgery had an increase in total spine height from 20 cm preimplantation to 28 cm by the 15th lengthening. They maintained greater than 75% of expected age-matched spine growth until age 10 years and lengthening procedures did not appear to follow a law of diminishing returns. Rib-based distraction is an effective means of maintaining spine growth which is likely beneficial for pulmonary development as compared with the natural history of EOS. LEVEL OF EVIDENCE: Level IV-Therapeutic study, case series.

Use of Rib-Based Distraction in the Treatment of Early-Onset Scoliosis Associated With Neurofibromatosis Type 1 in the Young Child.

STUDY DESIGN: This study was an institutional review board-approved retrospective review of a prospectively collected multicenter database for rib-based distraction systems used in the treatment of young children with early-onset scoliosis associated with neurofibromatosis type 1 (NF-1). OBJECTIVE: To evaluate the effectiveness of rib-based distraction and associated complications in managing scoliosis in the growing child with NF-1. SUMMARY OF BACKGROUND DATA: Patients with NF-1 commonly have scoliosis with curves that can be dysplastic and progressive and respond poorly to bracing. Rib-based distraction systems have recently been described in the management of these complex patients. The efficacy and complication rate using these systems have not previously been reported. METHODS: Twelve children with NF-1 and scoliosis who were treated with rib-based distraction systems were identified from a prospectively collected multicenter registry. Preoperative and postoperative Cobb angle and T1-S1 spine height were measured from posteroanterior radiographs. The number of lengthenings, age at implantation, years of follow-up, and complications were also acquired from the registry or patient charts. RESULTS: Mean age at implantation of the Vertical Expandable Prosthetic Titanium Rib device was 6.34 years. Mean preoperative Cobb angle was 66.3°. Average follow-up was 5.2 years. Mean postoperative Cobb angle was 60.8° after an average of 7.75 lengthening procedures (range, 2-16 procedures). T1-S1 height increased in all patients. There were 17 complications in 8 patients (device migration in 6, wound dehiscence in 3, rod breakage in 2, medical issues in 5, and 1 revision for progression of curve). Of the 17 complications, 10 were grade I, 1 was grade II, and 6 were grade IIA; there were no grade III complications. CONCLUSIONS: The use of rib-based distraction is an effective and relatively safe method of stabilizing curve progression through growth in severe dysplastic scoliosis associated with NF-1.

Reliability of Proximal Junctional Kyphosis Measurements for Young Children With Scoliosis.

DESIGN: Retrospective comparison. OBJECTIVES: To determine whether the choice of proximal junctional kyphosis (PJK) definition affects reported rates and reliability of measurement of PJK for the same group of children treated with growth-friendly surgery. BACKGROUND: Distraction-based surgery has been associated with the development of PJK, which may lead to premature implant failure and may affect the upper instrumented level. Proximal junctional kyphosis has not been clearly defined in the literature and recent studies have used various definitions, resulting in widely varying rates of PJK. As a first step toward defining risk factors that may lead to clinically significant PJK, an evaluation of definitions of PJK should be performed. METHODS: The researchers analyzed radiographs of 36 children who were treated with growth-friendly surgery. The rates of PJK were determined using 3 recently described definitions. Five observers each measured the radiographs 2 weeks apart. Reliability was measured using the kappa statistic and intraclass correlation. RESULTS: At 2-year follow-up, rates of PJK varied between 6% and 42% depending on the definition used. Interobserver agreement for PJK at time 1 yielded fair agreement for definition 1 (κ = 0.31), moderate for definition 2 (κ = 0.40), and fair for definition 3 (κ = 0.38). Interobserver agreement for junctional angle at time 1 was fair (intraclass correlation coefficient [ICC], 0.48) for definition 1, good (ICC, 0.71) for definition 2, and fair (ICC, 0.55) for definition 3. Intra-observer agreement between times 1 and 2 for junctional angle was good (ICC, 0.61) for definition 1, excellent (ICC, 0.82) for Definition 2, and good (ICC, 0.69) for definition 3. CONCLUSIONS: When assessed with the same group of children, rates of PJK varied depending on the definition used. Interobserver reliability was fair to moderate; however, better interobserver and intra-observer agreement were noted with definition 2.

Prevalence of physical signs in cervical myelopathy: a prospective, controlled study.

STUDY DESIGN: Prospective case-control study. OBJECTIVE: To determine the prevalence and utility of commonly tested myelopathic signs in surgically treated patients with cervical myelopathy (CM). SUMMARY OF BACKGROUND DATA: Although physical signs are sought in making the diagnosis of CM, their importance remains unclear, as patients with CM may have normal examinations while those without CM can demonstrate "myelopathic" signs. METHODS: Patients presenting with cervical complaints and advanced imaging were evaluated over a 6-month interval in a single surgical practice. The CM group consisted of those with (1) a history of myelopathic symptoms and (2) correlative spinal cord compression on imaging, who then (3) underwent surgery and (4) improved Nurick score by > or = 1 grade after surgery. The controls consisted of patients with neck/radicular complaints but no myelopathic symptoms and no cord compression on imaging. Myelopathic signs included hyperreflexia or provocative signs (Hoffman inverted brachioradialis reflex, clonus, Babinski). RESULTS: There were 39 CM patients and 37 controls. Myelopathic signs were more prevalent in the CM group (79% vs. 57%; P = 0.05), with significantly higher rates of all provocative signs but not hyperreflexia. Overall, myelopathic signs were not highly sensitive in diagnosing the presence of CM, as 21% of CM patients failed to demonstrate any myelopathic signs. There was no correlation between the presence of myelopathic signs and diabetes or preoperative Nurick score. However, those with cord signal changes were significantly more likely to demonstrate myelopathic signs. CONCLUSION: Although myelopathic signs are significantly more common in CM patients, they may be negative in approximately one-fifth and can not be relied on to make the diagnosis. In patients who lack myelopathic signs but otherwise seem myelopathic with no alternative explanations, symptoms combined with correlative imaging studies must be used to base treatment decisions, as the absence of signs does not preclude the diagnosis of myelopathy nor its successful surgical treatment.