Delays in Obtaining Knee MRI in Pediatric Sports Medicine: Impact of Insurance Type.

BACKGROUND: Increased enrollment in government-based insurance plans has been reported. With youth sports injuries on the rise, increased ordering of advanced imaging such as magnetic resonance imaging (MRI) has occurred. This study sought to report on the impact of insurance type on access to and results of knee MRI in pediatric sports medicine patients. METHODS: A retrospective review of 178 consecutive pediatric sports medicine clinics was completed. INCLUSION CRITERIA: patients younger than 18 years, routine knee MRI ordered, sports medicine diagnosis, and insurance. Data included basic demographics, injury date, date and location (urgent care vs. clinic) of the first presentation, details of MRI ordering and approval, date and location of MRI follow-up, MRI results (negative, minor findings, major findings), and eventual treatment required. RESULTS: A total of 168 charts underwent a complete review. The patients' average age was 14±3 years and 54% (N=90) were female. Ninety-eight had government insurance and 70 had commercial insurance. The time between injury and MRI completion was significantly longer with government insurance (34 vs. 67 d, P<0.01). Government insurance had increased wait time between the first visit and MRI completion (11 vs. 40 d, P<0.001) as well as MRI order and completion (9 vs. 16.5 d, P<0.001). There was no significant difference in positive findings on MRI between insurance groups, including both major and minor findings nor in the proportion receiving eventual operative treatment. CONCLUSION: Pediatric sports medicine patients with government insurance have delays in obtaining knee MRI, despite there being no difference in the rate of positive findings and subsequent operative treatments. LEVEL OF EVIDENCE: Level III-case-control study.

Iliotibial band autograft: what size is the graft? A mathematical and cadaveric model : ITB single and double strand size.

BACKGROUND: The iliotibial band (ITB) is used in anterior cruciate ligament (ACL) reconstruction in skeletally immature patients as well as several other orthopedic reconstructions. The purpose of this study is to determine the size of the ITB as an autograft option in ACL reconstruction surgery or other orthopedic soft tissue reconstructions. METHODS: Five adult cadavers resulting in nine ITB were used. Thickness and width of the ITB were determined. Using ITB width of 15-60 mm, single and doubled graft sizes were determined using standard surgical graft size technique. Geometric calculations based on average graft thickness were used to mathematically confirm the graft size of the ITB. RESULTS: The ITB is less than 1 mm in thickness in males and females. Cadaveric measurements were less than 1 mm larger than mathematical measurements, in majority of measurements. ITB autograft can be harvested to a maximum 9 mm single-stranded graft or > 12 mm doubled graft. A minimum of 50 mm of ITB width is required to make a 8 mm graft. CONCLUSIONS: ITB is a versatile graft that can be used for a graft size up to 9 mm single strand and over 12 mm double strand. A minimum of 50 mm width of ITB is required to obtain a 8 mm-diameter autograft. To ensure appropriate graft size, surgeons should consider harvesting the maximum amount of ITB when performing ACL reconstructions in skeletally immature patients. CLINICAL RELEVANCE: Surgeons have a quick reference for the width of ITB they should harvest based on the size of graft they require for a successful surgery.

Hamstring Autograft Too Small: How Much Allograft Do You Need to Supplement to a Desired Hybrid Graft Size?

PURPOSE: To determine a simple rule for choosing supplemental allograft size for hybrid anterior cruciate ligament reconstruction using mathematical and cadaveric models. METHODS: Mathematical and cadaveric models were used to determine the rule. The mathematical model required application of the geometric Pythagorean theorem to add areas of circles. Cadaveric semitendinosus and gracilis tendons were combined in multiple quadrupled hamstring size combinations and then sized using standard surgical techniques to confirm the mathematical model. RESULTS: Geometric measurement, not simple addition, of graft diameters was required to determine the final graft size. Direct comparison of cadaveric and mathematical models showed close relations. If a final graft size of 7 mm is desired, an added diameter of all grafts of approximately 9.5 mm is needed. If a final graft size of 8 mm is desired, an added diameter of all grafts of approximately 11 mm is needed. If a final graft size of 9 mm is desired, an added diameter of all grafts of approximately 12.5 mm is needed. If a final graft size of 10 mm is desired, an added graft diameter of approximately 14 mm is needed. Cadaveric hamstring measurements were similar to the mathematical model. CONCLUSIONS: By use of mathematical and cadaveric models, simple rules for determining the additional size of allograft diameter needed to supplement undersized hamstring autograft were created. CLINICAL RELEVANCE: With the increasing availability of allograft types and sizes, surgeons currently have no guidelines on the size of allograft that is required to supplement an undersized hamstring autograft. Simple rules were created for determining the amount of allograft supplementation required for undersized hamstrings and are easily applied to clinical situations.

Defining a Safe Zone for All-Inside Lateral Meniscal Repairs in Pediatric Patients: A Magnetic Resonance Imaging Study.

PURPOSE: To establish a safe zone for all-inside meniscal fixation in pediatric patients by use of magnetic resonance imaging (MRI) measurements between the popliteal tendon (PT) and popliteal neurovascular bundle (PNVB). METHODS: Patients aged 5 to 16 years with normal or nearly normal knee MRI scans were included. They were grouped by age: group I, 5 to 7 years (n = 61); group II, 8 to 10 years (n = 59); group III, 11 to 13 years (n = 60); and group IV, 14 to 16 years (n = 70). At the level of the lateral meniscus, 2 lines starting at the lateral patellar tendon border and ending at the medial edge of the PT (D1) and the lateral edge of the PNVB (D2) were made on an axial knee MRI scan. A third line (D3) connected D1 to D2 at the meniscocapsular junction of the posterior horn of the lateral meniscus (PHLM). A fourth line (D4), derived geometrically, was parallel and 8 mm anterior to D3, simulating the anterior edge of the PHLM. RESULTS: Axial MRI scans of 250 pediatric patients (aged 5-16 years) were retrospectively reviewed. Analysis showed significant correlation between age and sex for D3 (P < .0001). For D3, there were significant differences among all age groups, except between groups III and IV. The average D3 by age group was 14.1 mm (standard deviation [SD], 3.1 mm) for group I, 15.8 mm (SD, 2.5 mm) for group II, 17.0 mm (SD, 3.3 mm) for group III, and 17.2 mm (SD, 3.1 mm) for group IV. The average D4 was 11.39 mm (SD, 2.6 mm), 13.24 mm (SD, 2.24 mm), 14.59 mm (SD, 2.89 mm), and 14.80 mm (SD, 2.79 mm), respectively. There were significant differences in D3 and D4 in male versus female patients (17.6 mm vs 15.7 mm, P < .001, and 14.9 mm vs 13.2 mm, P < .001, respectively), particularly in groups III and IV (17.0 mm vs 13.8 mm and 16.8 mm vs 13.9 mm, respectively). CONCLUSIONS: This study provides normative data of the distance between the PNVB and PT at the meniscocapsular junction (D3) and anterior edge of the PHLM (D4) with the knee in full extension. Combined with previous studies showing that the addition of knee flexion increases the distance between the meniscus and the neurovascular bundle, these data can be used by surgeons to improve the safety of PHLM repair in pediatric patients. LEVEL OF EVIDENCE: Level III, diagnostic study of nonconsecutive patients.

What's New in Pediatric Medial Epicondyle Fractures?

BACKGROUND: Medial epicondyle fractures are predominantly seen in adolescent, male patients. Historically, nonoperative intervention was the mainstay of treatment. With increasing upper extremity demands of young athletes and reports of valgus instability after nonoperative treatment, there has been an increased interest in operative indications. Controversy regarding proper imaging and measurement of displacement complicates decision-making algorithms. Review of recent literature is required for improved decision making. METHODS: We searched the PubMed database for all papers related to the treatment of medial epicondyle fractures in patients under 18 years of age published between January 1, 2005 and March 15, 2016. This resulted in 39 papers written in English for review. Papers were included based upon subject matter and contribution of new findings to literature. Review articles were excluded. RESULTS: In total, 39 papers were reviewed and 30 were included in this review. Five classic manuscripts on medial epicondyle fractures in children provide appropriate historical and background information as needed. CONCLUSIONS: Medial epicondyle fractures represent a variety of low and high-energy mechanisms, displacement, treatment options, and complications. This paper reviews recent literature on these topics. Controversy regarding imaging modality, displacement measurement accuracy, and surgical indications still exist. Long term, patient based, functional outcome studies of operative versus nonoperative treatment are needed to improve our treatment algorithms of this injury. Treatment algorithms should be individualized to each specific patient and fracture. LEVEL OF EVIDENCE: Level 5.

Flexibility of thoracic spines under simultaneous multi-planar loading.

PURPOSE: The corrective potential of two posterior-only destabilization procedures for scoliosis deformity was quantified under single and multi-planar loading using cadaveric spines. METHODS: Ten full-length human cadaveric thoracic spines were mounted in an 8-df servohydraulic load frame. Cyclic, pure moments were applied in: (1) flexion-extension, (2) lateral bending, (3) axial rotation, (4) flexion-extension with axial rotation, and (5) lateral bending with axial rotation at 0.5°/s, to ±4 Nm. Each specimen was tested intact, and again after nine en bloc bilateral total facetectomies, and one, two, three, and four levels of Ponte osteotomies. Motion was measured throughout loading using optical motion tracking. RESULTS: Under single-plane loading, facetectomies and Ponte osteotomies increased thoracic spine flexibility in all three planes. Compared to total facetectomies, higher per-level increases were seen following Ponte osteotomies, with increases in total range of motion (total ROM) of up to 2.7° in flexion-extension, 1.4° in lateral bending, and 3.1° in axial rotation following each osteotomy. Compared to the facetectomies, four supplemental osteotomies increased total ROM by 23 % in flexion (p < 0.01) and 8 % in axial rotation (p < 0.01). Increases in lateral bending were smaller. Under multi-planar loading, each Ponte osteotomy provided simultaneous increases of up to 1.4°, 1.6°, and 2.2° in flexion-extension, lateral bending, and axial rotation. CONCLUSIONS: Ponte osteotomies provided higher per-level increases in ROM under single-plane loading than total facetectomies alone. Further, Ponte osteotomies provided simultaneous increase in all three planes under multi-planar loading. These results indicated that, to predict the correction potential of a surgical release, multi-planar testing may be necessary.

Temporal relation of meniscal tear incidence, severity, and outcome scores in adolescents undergoing anterior cruciate ligament reconstruction.

PURPOSE: Anterior cruciate ligament (ACL) rupture is increasingly common in adolescents. Time between ACL rupture and surgical reconstruction, surgical wait time, is related to concurrent meniscal tear incidence and possibly tear pattern. This study defines the relationship between meniscal tear characteristics and surgical wait time in adolescents with ACL rupture. METHODS: One-hundred and twenty-one consecutive adolescent (median age 16.1 years, range 9-19 years) ACL rupture patients undergoing primary ACL reconstruction were studied. All had documented surgical wait time, preoperative and 6-month post-operative outcome (Lysholm and pedi-IKDC) scores, and intraoperative meniscus tear characteristics. Meniscal tear severity was graded according to the Lawrence and Anderson system: non-surgical: grade 1; reparable: grade 2-3; irreparable: grade 4-5. Significant tears were defined as at least grade 2. RESULTS: Average age at surgery was 16.1 years. 48.7 % had surgical wait time greater than 6 months. 42.5 % of menisci were torn. With surgical wait time <6 months, there were more lateral than medial tears (48 vs 21 %, p = 0.001). With surgical wait time >6 months, medial tear incidence increased (50 vs 21 %, p < 0.001), there were more significant tears (63 vs 42 %, OR 2.3, p = 0.02), and preoperative Lysholm and pedi-IKDC scores were lower (58 vs 74, p < 0.001; 52 vs 61, p < 0.007). Scores were lower in patients with meniscus tears (63.8 vs 69.3, n.s.; 53.9 vs 60.5, p = .04). Patients with public insurance had risks of surgical wait time greater than 3 months (OR 12.4, p < 0.001) and 6 months (OR 7.8, p < 0.001), and of a significant meniscus tear (OR 2.5, p = 0.03). Six-month post-operative pedi-IKDC scores improved more in meniscus tear patients (28.4 vs 21, p = 0.05). CONCLUSIONS: This study shows a significant increase in medial meniscal tear incidence, decrease in preoperative scores, and worse tear severity with surgical wait time >6 months. Public insurance was a risk factor for longer surgical wait time and meniscus tear.

Primary osteoblast-like cells from patients with end-stage kidney disease reflect gene expression, proliferation, and mineralization characteristics ex vivo.

Osteocytes regulate bone turnover and mineralization in chronic kidney disease. As osteocytes are derived from osteoblasts, alterations in osteoblast function may regulate osteoblast maturation, osteocytic transition, bone turnover, and skeletal mineralization. Thus, primary osteoblast-like cells were cultured from bone chips obtained from 24 pediatric ESKD patients. RNA expression in cultured cells was compared with RNA expression in cells from healthy individuals, to RNA expression in the bone core itself, and to parameters of bone histomorphometry. Proliferation and mineralization rates of patient cells were compared with rates in healthy control cells. Associations were observed between bone osteoid accumulation, as assessed by bone histomorphometry, and bone core RNA expression of osterix, matrix gla protein, parathyroid hormone receptor 1, and RANKL. Gene expression of osteoblast markers was increased in cells from ESKD patients and signaling genes including Cyp24A1, Cyp27B1, VDR, and NHERF1 correlated between cells and bone cores. Cells from patients with high turnover renal osteodystrophy proliferated more rapidly and mineralized more slowly than did cells from healthy controls. Thus, primary osteoblasts obtained from patients with ESKD retain changes in gene expression ex vivo that are also observed in bone core specimens. Evaluation of these cells in vitro may provide further insights into the abnormal bone biology that persists, despite current therapies, in patients with ESKD.

Relationship Between Age and Pathology With Treatment of Pediatric and Adolescent Discoid Lateral Meniscus: A Report From the SCORE Multicenter Database.

BACKGROUND: Surgical treatment options of discoid lateral meniscus in pediatric patients consist of saucerization with or without meniscal repair, meniscocapular stabilization, and, less often, subtotal meniscectomy. PURPOSE: To describe a large, prospectively collected multicenter cohort of discoid menisci undergoing surgical intervention, and further investigate corresponding treatment of discoid menisci. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A multicenter quality improvement registry (16 institutions, 26 surgeons), Sports Cohort Outcomes Registry, was queried. Patient characteristics, discoid type, presence and type of intrasubstance meniscal tear, peripheral rim instability, repair technique, and partial meniscectomy/debridement beyond saucerization were reviewed. Discoid meniscus characteristics were compared between age groups (<14 and >14 years old), based on receiver operating characteristic curve, and discoid morphology (complete and incomplete). RESULTS: In total, 274 patients were identified (mean age, 12.4 years; range, 3-18 years), of whom 55.6% had complete discoid. Meniscal repairs were performed in 55.1% of patients. Overall, 48.5% of patients had rim instability and 36.8% had >1 location of peripheral rim instability. Of the patients, 21.5% underwent meniscal debridement beyond saucerization, with 8.4% undergoing a subtotal meniscectomy. Patients <14 years of age were more likely to have a complete discoid meniscus (P < .001), peripheral rim instability (P = .005), and longitudinal tears (P = .015) and require a meniscal repair (P < .001). Patients ≥14 years of age were more likely to have a radial/oblique tear (P = .015) and require additional debridement beyond the physiologic rim (P = .003). Overall, 70% of patients <14 years of age were found to have a complete discoid meniscus necessitating saucerization, and >50% in this young age group required peripheral stabilization/repair. CONCLUSION: To preserve physiological "normal" meniscus, a repair may be indicated in >50% of patients <14 years of age but occurred in <50% of those >14 years. Additional resection beyond the physiological rim may be needed in 15% of younger patients and 30% of those aged >14 years.

Outcome assessment in neuromuscular spinal deformity.

Patient-based outcome measures are important tools quantifying the disease-specific and/or global quality of life (QOL) effects of spinal deformity treatment. In patients with neuromuscular disorders such as cerebral palsy, muscular dystrophy, and myelomeningocele, treatment effects must be differentiated from underlying disease functional impairments. In general, the goals of spinal surgery in these patients are to improve QOL by enhancing sitting balance and posture, improving lung and gastrointestinal function, and reducing pain and deformity. In selected patients, improving ambulation and hand function may also be realistic surgical goals. QOL measures specific to both the neuromuscular diagnosis and spinal deformity provide higher quality information on treatment outcomes for a particular patient than standard radiographic measures. This article reviews patient-based outcome measures in spinal deformity patients with neuromuscular disorders, including their development and use in comparative outcome studies in the recent literature.

Arthroscopic Treatment of Symptomatic Discoid Lateral Meniscus and Nondiscoid Meniscus in Adolescent Patients.

BACKGROUND: Discoid lateral meniscus (DLM) is a rare condition. Patient-reported outcomes using validated instruments are underreported in the literature. DLM outcomes have not been directly compared with nondiscoid meniscus (non-DLM) in adolescent patients. PURPOSE/HYPOTHESIS: This study sought to analyze the difference in patient characteristics, surgical treatment, and patient-reported outcomes for adolescent patients arthroscopically treated for symptomatic DLM and non-DLM pathology. We hypothesized that DLM and non-DLM patient-reported outcomes would be similar. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A retrospective review of patients aged <18 years with symptomatic DLM and non-DLM pathology was completed between 2015 and 2021 at a single academic institution. Chart reviews for patient characteristics and surgical operative indications and technique were completed. Patient-reported outcome scores were prospectively collected preoperatively and at 6 months, 1 year, and 2 years after surgery. RESULTS: Patients in the DLM group (n = 48), when compared with the non-DLM group (n = 45), were younger (12.71 vs 15.78 years, respectively; P < .001) and had lower body mass index (24.53 vs 28.91, respectively; P < .02). Both groups were majority Hispanic and more commonly male (DLM 65% vs non-DLM 60%). All of the DLM patients had surgery on the lateral discoid meniscus (n = 48), whereas the non-DLM group had surgery on the lateral meniscus (n = 37), medial meniscus (n = 7), or both (n = 1). A majority of patients in both groups underwent meniscal repair (DLM 73% and non-DLM 62%), and there was no difference in surgical treatment between groups (P > .05). A statistically significant improvement was seen in International Knee Documentation Committee (IKDC) and Physical Activity Questionnaire (PAQ) scores from the preoperative assessment to 6 months, 1 year, and 2 years after surgery for both DLM and non-DLM groups (P < .05). No difference was found in scores between DLM and non-DLM groups, between sexes, or between age groups (<13 years or ≥13 years) (P > .05). CONCLUSION: Although patients with DLM were younger and had lower body mass index, the IKDC and PAQ scores were not significantly different between the DLM and non-DLM groups. Both groups showed a significant improvement in scores relative to their preoperative scores. Sex and age did not affect IKDC or PAQ scores.

Bone mineral density and functional measures in patients with arthrogryposis.

BACKGROUND: Patients with arthrogryposis often report decreased ambulation and physical activity. Given that skeletal mineralisation is responsive to force, we identified the need to characterize bone mineral density and functional measures in this population, and conducted a cross-sectional study to establish a reference for future investigations. METHODS: Thirty consecutive patients aged 5 to 18 years with either the diagnosis of amyoplasia or nonsyndromic arthrogryposis with predominantly lower extremity involvement underwent bone densitometry testing, and lumbar spine Z-scores were calculated against an age and sex-matched control population as is customary in children. Pediatric outcomes data collection instrument (PODCI) and functional independence measure for Children (WeeFIM) assessment forms were completed. Mean Z-scores, PODCI, and WeeFIM scores were calculated. Statistical analysis was performed to compare lumbar spine Z-scores between patients divided by ambulatory status and to correlate WeeFIM and PODCI scores. RESULTS: Mean lumbar spine Z-score was -0.47, with 73% of Z-scores being <0. Mean Z-score among nonambulators or home ambulators was -1.05, as compared to a mean Z-score among limited and unlimited community ambulators of -0.14 with a trend toward significance (P=0.10), and a dose-response relationship between higher bone density and increasing ambulatory function. Mean WeeFIM self-care and mobility quotient scores were 67.5/100 and 70.9/100, respectively. PODCI normative scores were decreased for upper extremity (10/50), transfer/basic mobility (-17/50), and sports/physical function (4/50), but normal in pain/comfort (45/50) and happiness (49/50). A linear relationship was noted between functional ambulation level and WeeFIM quotient and PODCI normative scores. There was good correlation between WeeFIM mobility and PODCI transfers and basic mobility standardised scores (R=0.86). CONCLUSIONS: This is the first study to measure bone mineral density in children with arthrogryposis, and shows it to be lower than age-matched means, especially in patients with limited ambulation. Objective measures of functional ability (WeeFIM and PODCI) are decreased and demonstrate a linear relationship with ambulatory level. Further investigation is needed to quantify long-term effects of entering adulthood with below average bone mineral density in patients with arthrogryposis. LEVEL OF EVIDENCE: Level II.

Prospective Study of Acute Opioid Use After Adolescent Anterior Cruciate Ligament Reconstruction Shows No Effect From Patient- or Surgical-Related Factors.

INTRODUCTION: Patient-reported pain scores and opioid use have not been quantified after outpatient adolescent anterior cruciate ligament reconstruction (ACLR). METHODS: Patients aged 12 to 18 years undergoing primary isolated ACLR, with or without meniscal treatment, were prospectively recruited. Patients actively taking opioids or with previous extended use of opioids were excluded. Two orthopaedic surgeons performed ACLR and determined the use of a hamstring or bone-patellar tendon-bone autograft. For postoperative pain management, patients were prescribed 40 tablets of hydrocodone/acetaminophen 5/325 mg. Patients were instructed to document daily pill consumption and side effects through a daily log for 6 weeks. Patients completed the American Pain Society Patient Outcome Questionnaire at the end of weeks 1 and 6. RESULTS: One hundred three patients were enrolled, with age: 12.5 to 18.9 years (mean 16.2 y ± 1.3), weight: 41.3 to 113.6 kg (mean 72.4 kg ± 17.2), and body mass index: 17.8 to 40.1 (mean 25.9 ± 4.9). Sixty-nine patients received a hamstring autograft, and 34 received a bone-patellar tendon-bone autograft. Fifty-six received additional meniscal procedures. The median number of postoperative opioids taken by patients was 17 (range 0 to 40). No notable differences were found in total pill consumption with regard to age, weight, body mass index, sex, block type, autograft type, or meniscal treatment at 1 week post-op or 6 weeks post-op. No correlation was found between the self-reported "worst pain in the past 24 hours" at the end of the first postoperative week or after 6 weeks (r = 0.112, P = 0.26, and r = 0.093, P = 0.36). No correlation was found between the level of satisfaction with pain treatment and total number of pills taken during the first postoperative week or at the end of 6 weeks (r = -0.090, P = 0.37, and r = -0.172, P = 0.08). CONCLUSION: Patients take most pain medication during the first postoperative week after adolescent ACLR, although patient and surgical variables had no notable influence on pill consumption. LEVEL OF EVIDENCE: Level IV, case series.

Increasing loads and diminishing returns: a biomechanical study of direct vertebral rotation.

STUDY DESIGN: Biomechanical simulation of DVR and pure-moment testing on thoracic spines. OBJECTIVES: Characterize load-deformation response of thoracic spines under DVR maneuvers until failure, and compare to pure-moment testing of same spines. Despite reports of surgical complications, few studies exist on increase in ROM under DVR torque. Biomechanical models predicting increases from surgical releases have consistently used "pure-moments", a standard established for non-destructive measurement of ROM. Yet, DVR torque is not accurately modeled using pure moments and, moreover, magnitudes of torque applied during DVR maneuvers may be substantially higher than pure-moment testing. METHODS: Cadaveric thoracic spines (N = 11) were imaged, then prepared. Polyaxial pedicle screws were implanted at T7-T10 after surgical releases. Bilateral facetectomies and Ponte osteotomies were completed at T10-T11. A custom apparatus, mounted into an 8-dof MTS load frame, was used to attach to pedicle screws, allowing simulation of surgical DVR maneuvers. Motions of vertebrae were measured using optical motion tracking. Torque was increased until rupture of the T10-T11 disc or fracture at the pedicle screw sites at any level. The torque-rotation behavior was compared to its behavior under pure-moment testing performed prior to the DVR maneuver. RESULTS: Under DVR maneuvers, failure of the T10-T11 discs accompanied in most cases by pedicle screw loosening, occurred at 13.7-54.7 Nm torque, increasing axial rotation by 1.4°-8.9°. In contrast, pure-moment testing (4 Nm) increased axial rotation by only 0.0°-0.9°. CONCLUSIONS: DVR resulted in substantially greater correction potential increases compared to pure-moment testing even at the same torque. These results suggest increased flexibility obtained by osteotomies and facetectomies is underestimated using pure-moment testing, misrepresenting clinical expectations. The present study is an important and necessary step toward the establishment of a more accurate and ultimately surgically applied model. LEVEL OF EVIDENCE: III.

Vitamin D sterols increase FGF23 expression by stimulating osteoblast and osteocyte maturation in CKD bone.

Impaired osteoblast and osteocyte maturation contribute to mineralization defects and excess FGF23 expression in CKD bone. Vitamin D sterols decrease osteoid accumulation and increase FGF23 expression; these agents also increase osteoblast maturation in vitro but a link between changes in bone cell maturation, bone mineralization, and FGF23 expression in response to vitamin D sterols has not been established. We evaluated unmineralized osteoid accumulation, osteocyte maturity markers (FGF23: early osteocytes; sclerostin: late osteocytes), and osteocyte apoptosis in iliac crest of 11 pediatric dialysis patients before and after 8 months of doxercalciferol therapy. We then evaluated the effect of 1,25(OH)2vitamin D on in vitro maturation and mineralization of primary osteoblasts from dialysis patients. Unmineralized osteoid accumulation decreased while numbers of early (FGF23-expressing) increased in response to doxercalciferol. Osteocyte apoptosis was low but increased with doxercalciferol. Bone FGF23 expression correlated with numbers of early, FGF23-expressing, osteocytes (r = 0.83, p < 0.001). In vitro, 1,25(OH)2vitamin D increased expression of the mature osteoblast marker osteocalcin (BGLAP) but only very high (100 nM) concentrations affected in vitro osteoblast mineralization. High doses (10 and 100 nM) of 1,25(OH)2vitamin D also increased the ratio of RANKL/OPG expression in CKD osteoblasts. Vitamin D sterols directly stimulate osteoblast maturation. They also increase osteocyte turnover and increase osteoblast expression of osteoclast differentiation factors, thus likely modulating osteoblast/osteoclast/osteocyte coupling. By increasing numbers of early osteocytes, vitamin D sterols increase FGF23 expression in CKD bone.

Decreased body mass index and restrictive lung disease in congenital thoracic scoliosis.

BACKGROUND: Pediatric patients with congenital thoracic scoliosis often have restrictive lung disease and low body weight for age. In other patients with respiratory disorders, the work of breathing can increase basal metabolic demands and predispose patients to cachexia. The primary study aim was to determine if severity of restrictive lung disease, as measured by pulmonary spirometry, correlates to decreased body mass index (BMI) in patients with congenital thoracic scoliosis. A secondary study aim was to determine what patient factors and radiographic measures correlate to low BMI. METHODS: Forty-nine consecutive patients with congenital thoracic scoliosis underwent pulmonary function testing, spinal radiographs, and BMI percentile for age calculations. Severity of restrictive lung disease was quantified by the forced vital capacity percentile (FVC%). The BMI percentile for age was also ranked as normal, moderately, or markedly decreased (0, <1, or <2 SDs below normal, respectively). The t tests were performed between BMI rank and FVC% as well as forced expiratory volume in 1 second (FEV1). A stepwise multivariate linear regression analysis was performed between BMI percentile and FVC%, age, sex, type and extent of previous spine fusion, radiographic measures, and pulmonary spirometry measures. RESULTS: The mean BMI percentile for all patients was 43% (range, 2%-98%). Both FVC% and FEV1 percentile were significantly decreased in patients with abnormal BMI (77% vs 51%, P = 2.78 *10(-1) for FVC%; 75% vs 52%, P = 0.00021 for FEV1 percentile). Multivariate analysis showed that FVC% was the only tested variable that significantly correlated to BMI percentile. There was a 13.6 times higher risk of having an abnormal BMI in patients with moderate to severe restrictive lung disease. CONCLUSIONS: Decreased pulmonary function compromise strongly correlates to low BMI in patients with congenital thoracic scoliosis. When considering moderate to severe restrictive lung disease as defined by FVC%, patients are at much higher risk of being significantly underweight. Body mass index is another important sign of thoracic insufficiency syndrome in these patients. LEVEL OF EVIDENCE: Prognostic case-control study, level III.

A novel method for determining sagittal pediatric patellar height with the Blumensaat-Epiphyseal Containment of the Knee Angle.

Defining normal pediatric patellar height is complicated. Current methods use ratios calculated from lateral radiographs, but often provide inconsistent results and are time-consuming. It has been observed that the angle formed by Blumensaat's line and the distal femoral physis, when extended, form an area of patellar containment throughout a range of knee flexion. Deemed the Blumensaat-Epiphyseal Containment of the Knee (BECK) Angle, the objective of this study was to investigate this as a simple alternative to identify normal pediatric patellar height. Lateral radiographs were taken every 15° from 0° to 90° flexion on 10 fresh-frozen cadaveric knees. Patellar height was measured as the percentage of pole-to-pole patellar length contained within the BECK angle. The method was then applied to normal lateral radiographs of 105 pediatric knees, divided into age groups of 7-9, 10-12, and 13-16 years old. BECK angle patellar containment was compared with previously described methods. For cadaveric specimens, at least 50% patellar containment occurred between 0° and 71° flexion without quadriceps tension and between 21° and 81° flexion with 30 N of quadriceps tension. For pediatric radiographs, flexion ranged from 9° to 81°. At least 50% patellar containment occurred in 96% of knees in all three age groups. Knee flexion fell within a range of 15°-60° in 92 of the 105 pediatric knees. Limiting the analysis to this range, at least 50% patellar containment occurred in 99% of knees in all three age groups. On the basis of this study, normal pediatric knee lateral radiographs between 15° and 60° flexion should show at least 50% patellar containment within the BECK angle. LEVEL OF EVIDENCE: Diagnostic Level II study.

Opioid Prescription and Usage in Adolescents Undergoing Orthopaedic Surgery in the United States: A Systematic Review.

BACKGROUND: The proper use of opioid analgesia for postoperative pain management is controversial. While opioids are considered the standard of care for multimodal postoperative pain modulation in the United States, there is a lack of established protocols for prescribing opioids in adolescents undergoing outpatient orthopaedic surgery. The objective of this review was to identify and report on current literature on opioid prescription for pain management in adolescents undergoing all procedures, as well as in adults undergoing outpatient orthopaedic surgery. METHODS: A comprehensive literature search using PRISMA guidelines was performed to identify all articles relevant to opioid use in adolescents for postoperative pain and in adults following outpatient orthopaedic procedures. RESULTS: A total of 4,446 results were identified from databases and relevant journal web sites. Of these, 9 articles were selected that fit the criteria for review. Five studies discussed the dosage and type of opioids prescribed in adolescent populations, and 4 quantified patient self-administration in adult populations. CONCLUSIONS: Adolescent opioid pain management following outpatient orthopaedic surgery is not documented. Current recommendations for opioid prescription in adolescents lack support and are primarily based on adult dosages. Adult studies suggest that opioid medications may be overprescribed following outpatient orthopaedic surgery. These results clearly indicate that there is a pressing need for quantitative research on pain management following outpatient orthopaedic surgery in the adolescent population in the United States. CLINICAL RELEVANCE: There appear to be no studies on self-administered opioid pain medication following orthopaedic surgery in an adolescent population, suggesting that there is no objective basis for the current prescription recommendations.

Radiographic outcome of soft-tissue surgery for hip subluxation in non-ambulatory children with cerebral palsy.

This study reviewed radiographs of non-ambulatory spastic tetraparetic cerebral palsy patients who underwent soft tissue hip surgery to address hip subluxation. Patients were under 10 years of age at surgery, had limited hip motion, and radiographic subluxation. At an average 7.4 years postoperatively, hips had a migration percentage in the normal range (0-15%) in 58 of 70 cases (83%). Hips with preoperative subluxation between 30 and 49% had a normal migration percentage in 18 of 21 cases (81%), and those over 50% in three of seven (43%) of cases. Soft tissue surgery alone, even in cases of moderate hip subluxation, can result in long-term radiographic hip stability.

Challenging the Conventional Standard for Thoracic Spine Range of Motion: A Systematic Review.

BACKGROUND: Segmental motion is a fundamental characteristic of the thoracic spine; however, studies of segmental ranges of motion have not been summarized or analyzed. The purpose of the present study was to present a summary of the literature on intact cadaveric thoracic spine segmental range of motion in each anatomical plane. METHODS: A systematic MEDLINE search was performed with use of the terms "thoracic spine," "motion," and "cadaver." Reports that included data on the range of motion of intact thoracic human cadaveric spines were included. Independent variables included experimental details (e.g., specimen age), type of loading (e.g., pure moments), and applied moment. Dependent variables included the ranges of motion in flexion-extension, lateral bending, and axial rotation. RESULTS: Thirty-three unique articles were identified and included. Twenty-three applied pure moments to thoracic spine specimens, with applied moments ranging from 1.5 to 8 Nm. Estimated segmental range of motion pooled means ranged from 1.9° to 3.8° in flexion-extension, from 2.1° to 4.4° in lateral bending, and from 2.4° to 5.2° in axial rotation. The sums of the range of motion pooled means (T1 to T12) were 28° in flexion-extension, 36° in lateral bending, and 45° in axial rotation. CONCLUSIONS: The pooled ranges of motion were similar to reported in vivo motions but were considerably smaller in magnitude than the frequently referenced values reported prior to the widespread use of biomechanical testing standards. Improved reporting of biomechanical testing methods, as well as specimen health, may be beneficial for improving on these estimations of segmental cadaveric thoracic spine range of motion.