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Dive into the research topics where Jonathan R. Schiller is active.

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Featured researches published by Jonathan R. Schiller.


Clinical Orthopaedics and Related Research | 2010

Brace Management in Adolescent Idiopathic Scoliosis

Jonathan R. Schiller; Nikhil A. Thakur; Craig P. Eberson

Skeletally immature patients with adolescent idiopathic scoliosis are at risk for curve progression. Although numerous nonoperative methods have been attempted, including physical therapy, exercise, massage, manipulation, and electrical stimulation, only bracing is effective in preventing curve progression and the subsequent need for surgery. Brace treatment is initiated as either full-time (TLSO, Boston) or nighttime (Charleston, Providence) wear, although patient compliance with either mode of bracing has been a documented problem. We review the natural history of adolescent idiopathic scoliosis, identify the risks for curve progression, describe the types of braces available for treatment, and review the indications for and efficacy of brace treatment.Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.


Journal of The American Academy of Orthopaedic Surgeons | 2012

Benign tumors of the spine.

Nikhil A. Thakur; Alan H. Daniels; Jonathan R. Schiller; Mauricio Valdes; John K. Czerwein; Alan Schiller; Sean M. Esmende; Richard M. Terek

Benign tumors in the spine include osteoid osteoma, osteoblastoma, aneurysmal bone cyst, osteochondroma, neurofibroma, giant cell tumor of bone, eosinophilic granuloma, and hemangioma. Although some are incidental findings, some cause local pain, radicular symptoms, neurologic compromise, spinal instability, and deformity. The evaluation of spinal tumors includes a thorough history and physical examination, imaging, sometimes laboratory evaluation, and biopsy when indicated. Appropriate treatment may be observational (eg, eosinophilic granuloma) or ablative (eg, osteoid osteoma, neurofibroma, hemangioma), but generally is surgical, depending on the level of pain, instability, neurologic compromise, and natural history of the lesion. Knowledge of the epidemiology, common presentation, imaging, and treatment of benign bone tumors is essential for successful management of these lesions.


Journal of Bone and Joint Surgery, American Volume | 2013

Management of the pediatric pulseless supracondylar humeral fracture: Is vascular exploration necessary?

Amanda Weller; Sumeet Garg; A. Noelle Larson; Nicholas D. Fletcher; Jonathan R. Schiller; Michael Kwon; Lawson A. Copley; Richard Browne; Christine A. Ho

BACKGROUND Radically different conclusions exist in the pediatric orthopaedic and vascular literature regarding the management of patients with a pink hand but no palpable radial pulse in association with a supracondylar humeral fracture. METHODS One thousand two hundred and ninety-seven consecutive, operatively treated supracondylar humeral fractures in patients presenting to a level-I pediatric trauma center from January 2003 through December 2007 were studied retrospectively. Clinical records were reviewed to determine vascular and neurological examination findings, Gartland classification, timing of surgery, and postoperative complications. RESULTS One thousand two hundred and sixty-six patients had a documented radial pulse examination at the time of arrival in the emergency room; fifty-four (4%) of those patients lacked a palpable radial pulse. All fifty-four patients had type-3 fractures. Five (9%) of the fifty-four patients underwent open exploration of vascular structures on the basis of clinical findings of a pale hand, sluggish capillary refill, and/or weak or no pulse detected with use of Doppler ultrasound after closed reduction and percutaneous pinning. All five underwent vascular surgery to restore blood flow (two primary repairs, three saphenous vein grafts). Twenty (37%) of the fifty-four patients had a pulse documented with use of Doppler ultrasound and a pink hand after closed reduction and percutaneous pinning, but the radial pulse remained nonpalpable. These patients were observed in the hospital for signs of ischemia; one of the twenty patients required vascular repair after developing a pale hand nine hours after closed reduction and percutaneous pinning, and the other nineteen patients were also observed while they were in the hospital, and they all regained a palpable pulse either prior to discharge or by the time of the first postoperative visit. When compared with the group of patients with type-3 fractures for whom data regarding nerve examination were available, patients with type-3 fractures who lacked a palpable radial pulse had a higher rate of nerve palsy postoperatively (31% versus 9%, p < 0.0001). CONCLUSIONS In this cohort, nearly 10% of patients who presented with a type-3 supracondylar humeral fracture and no palpable radial pulse underwent immediate vascular repair to restore blood flow following closed reduction and percutaneous pinning. However, in our series, the lack of a palpable radial pulse after closed reduction and percutaneous pinning was not an absolute indication to proceed with vascular exploration if clinical findings (i.e., Doppler signal and capillary refill) suggested that the limb was perfused. Careful inpatient monitoring of these patients postoperatively is mandatory to identify late-developing vascular compromise. LEVEL OF EVIDENCE Prognostic level III. See Instructions for Authors for a complete description of levels of evidence.


Journal of Pediatric Orthopaedics | 2007

Increased lengthening rate decreases expression of fibroblast growth factor 2, platelet-derived growth factor, vascular endothelial growth factor, and CD31 in a rat model of distraction osteogenesis.

Jonathan R. Schiller; Douglas C. Moore; Michael G. Ehrlich

Background: The rate of lengthening has a profound impact on bone regeneration during distraction osteogenesis. Rapid distraction can delay or completely inhibit union, whereas distracting too slowly may lead to premature consolidation. However, the mechanisms responsible for retardation of healing due to rapid distraction have not been elucidated. This study explored whether rapid distraction alters the expression of certain angiogenic growth factors, in particular, fibroblast growth factor 2 (FGF-2), vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF-AA), and subsequent new vessel formation as evidenced by platelet endothelial cellular adhesion marker expression (CD31), an indicator of vascular budding. Methods: Unilateral femoral lengthenings were performed in 60 male Sprague-Dawley rats using a protocol that involved a 7-day latency period and distraction rates of either 0.5 (slow distraction) or 1.5 mm/d (fast distraction) for a total of 7.0 mm of lengthening. Animals were euthanized on postoperative days 8, 10, 12, 14, and 21 (n = 6 per time point and distraction rate). Expression of FGF-2, VEGF, PDGF-AA, and CD31 was characterized immunohistochemically. Results: Cellular staining of FGF-2, PDGF-AA, VEGF, and CD31 was reduced on days 8 to 12 in the regenerate of the fast-distraction animals compared with the slow-distraction animals. Staining of all growth factors was weak on days 14 and 21 at the slow rate and absent at the fast rate. Regardless of time point, a similar spatial localization of growth factor expression was observed at the 2 rates of distraction. Conclusions: The reduced expression of angiogenic growth factors and CD31, a marker of new vessel formation, indicates that the angiogenic cascade and new vessel formation required for effective bone healing is disrupted at a distraction rate of 1.5 mm/d in a rat model of limb lengthening. Clinical Relevance: Delayed bone healing with rapid distraction may be due in part to decreased cellular signaling required for angiogenesis. It may be possible to improve bone healing at increased distraction rates with the appropriately timed administration of growth factors.


Journal of Pediatric Orthopaedics | 2014

Clinical characteristics of severe supracondylar humerus fractures in children.

Sumeet Garg; Amanda Weller; A. Noelle Larson; Nicholas D. Fletcher; Michael Kwon; Jonathan R. Schiller; Richard Browne; Lawson A. Copley; Christine A. Ho

Background: The safety of delayed surgical treatment of severe supracondylar elbow fractures in children remains debated. No large studies have evaluated complications of injury and surgery evaluating only type 3 fractures. Our aim was to review the results of our experience treating children with severe supracondylar elbow fractures at various time points after injury. Methods: All children treated operatively for supracondylar humerus fractures from 2004 to 2007 at a single pediatric trauma center were identified. A total of 1296 children had operative treatment, of which 872 had type 3 fractures. Clinical records were reviewed to identify time to surgery from presentation at our institution. Patients were grouped into 4 cohorts [<6 h (n=325), 6 to 12 h (n=224), 12 to 24 h (n=295), and >24 h (n=28)]. Emergency, operative, inpatient, and outpatient records were reviewed to determine morbidity at presentation as well as operative and postoperative complications. Results: There was no difference in sex, age, or energy mechanism between children in the various time groups. An absent pulse was found in 54 children (6%) at presentation, of which only 5 ultimately required a vascular intervention. Nerve injury occurred in 105 patients (12%). Use of a medial entry pin was not associated with ulnar nerve injury. Increased time from presentation to surgery was not associated with increased morbidity from the injury or treatment complications. In contrast, there was a trend to steady decrease in morbidity and complication rates with increased time to surgery. Conclusions: This is the largest single-center study of severe supracondylar humerus fractures and describes rates of vascular compromise, nerve injury, infection, and other complications of these injuries. Most children with type 3 supracondylar humerus fractures can be treated safely in a delayed manner. Appropriate clinical judgment is imperative to optimize outcomes. Level of Evidence: Level III—retrospective comparative study.


Journal of Pediatric Orthopaedics | 2014

Operative treatment of type II supracondylar humerus fractures: does time to surgery affect complications?

A. Noelle Larson; Sumeet Garg; Amanda Weller; Nicholas D. Fletcher; Jonathan R. Schiller; Michael Kwon; Richard Browne; Lawson A. Copley; Christine A. Ho

Background: Because of the changing referral patterns, operative pediatric supracondylar humerus fractures are increasingly being treated at tertiary referral centers. To expedite patient flow, type II fractures are sometimes pinned in a delayed manner. We sought to determine if delay in surgical treatment of modified Gartland type II supracondylar humerus fractures would affect the rate of complications following closed reduction and percutaneous pinning. Methods: We performed a retrospective review of a consecutive series of 399 modified Gartland type II supracondylar fractures treated operatively at a tertiary referral center over 4 years. Mean patient age in the type II group was 5 years (range, 1 to 15 y). A total of 48% were pinned within 24 hours, 52% pinned >24 hours after the injury. Results: No difference was in detected in rates of major complications between the early and delayed treatment group. Four percent of patients sustained a complication (16 patients). There were no compartment syndromes, vascular injuries, or permanent nerve injuries. Complications included nerve injury (3), physical therapy referral for stiffness (3), pin site infection (2 treated with oral antibiotics, 4 treated with debridement), refracture (2), and loss of fixation or broken hardware (2). Of the 3 patients who sustained nerve injuries, all underwent surgery within 24 hours of injury. One patient developed an ulnar motor and sensory nerve palsy after fixation with crossed K-wires. This resolved by 7 weeks postoperatively. Two patients presented with an anterior interosseous nerve palsy—1 resolved 1 week after surgery, the other by 8 weeks postoperatively. Conclusions: Delay in surgery did not result in an increased rate of major complications following closed reduction and percutaneous pinning of type II supracondylar humerus fractures in children. Further prospective work is necessary to determine if there are subtle treatment benefits from emergent treatment of type II supracondylar humerus fractures. Level of Evidence: Level III—retrospective comparative series.


Sports Medicine and Arthroscopy Review | 2008

Spinal Deformity and Athletics

Jonathan R. Schiller; Craig P. Eberson

Exercise and athletic competition for the young individual has become increasingly more important in society. Scoliosis and Scheurmann kyphosis are spinal deformities prevalent in up to 2% to 3% and 7% of the population respectively, requiring nonoperative and occasionally operative treatment. Curve progression and patient physiologic age dictate treatment regimens. Bracing and physical therapy is the mainstay for nonoperative treatment, whereas soft tissue releases and fusion with instrumentation are used for operative correction. Athletic activity and sports participation is usually allowed for patients undergoing nonoperative treatment. Return to sport after surgical correction is variable, often decided by the treating surgeon, and based on the level of fusion and sporting activity. Although most treating surgeons promote some form of activity regardless of treatment modality chosen, caution should be taken when deciding on participation in collision activities such as football and wrestling.


Journal of Pediatric Orthopaedics | 2012

Increased severity of type III supracondylar humerus fractures in the preteen population.

Nicholas D. Fletcher; Jonathan R. Schiller; Sumeet Garg; Amanda Weller; A. Noelle Larson; Michael Kwon; Richard Browne; Lawson A. Copley; Christine A. Ho

Background: Supracondylar humerus fractures are the most common operative fractures in children; however, no studies describe the older child with this injury. The purpose of this study was to compare Gartland type III supracondylar humerus fractures in children older than 8 years of age with those in younger children than age 8. We hypothesized that there would be more complications in older children, reflecting a higher-energy injury mechanism. Methods: A retrospective chart review of supracondylar humerus fractures managed at a single level I pediatric trauma institution from 2004 to 2007 was performed. Patients with type III fractures were divided into groups based on age at presentation greater or less than 8. Baseline demographics, fracture characteristics, mechanism of injury, operative technique, and complications were analyzed. Results: A consecutive series of 1297 pediatric patients with surgically treated supracondylar humerus fractures was retrospectively reviewed including 873 (67.3%) type III fractures. Of those, 160 (18.3%) patients were older than age 8 at time of injury. Older children were more likely to have fractures from high-energy mechanisms (45.1% vs. 28.7%, P<0.001) and more open fracture (3.8% vs. 1.3%, P=0.0097). There was no difference in preoperative or iatrogenic neuropraxias between groups. There was a shorter delay between presentation and surgery in older children (mean, 217 vs. 451 min, P<0.0001). Three or more pins were used more often in older patients (61.8% in older children vs. 43.6% in younger children, P<0.0001). Major complications including reoperation, loss of fixation, or compartment syndrome were rare in both groups (1.1% in younger group vs. 0.6% in older group, P=1.000). There was a trend toward more pin site infections in older children (3.75% vs. 1.56%, P=0.071). Physical therapy was required nearly 4 times more frequently in older children for management of residual stiffness (20.0% vs. 5.7%, P<0.0001). Conclusions: Children older than 8 years of age have a higher rate of open supracondylar humerus fractures, although nerve injury rates are similar. Surgeons placed more pins for fixation of fractures in older patients and elbow stiffness requiring physical therapy occurred more commonly after surgical intervention. Evidence: III Retrospective cohort.


The Physician and Sportsmedicine | 2010

Anabolic Steroid Use in Adolescents: Identification of Those at Risk and Strategies for Prevention

Mary K. Mulcahey; Jonathan R. Schiller; Michael J. Hulstyn

Abstract Success in sports is often defined by winning, which drives athletes to use performance-enhancing drugs (PEDs) to gain an advantage over opponents. Over the past 20 years, use of PEDs by Olympic and professional athletes has led to public discussion regarding potential negative health effects and ethical implications of their use. Unfortunately, PEDs are not isolated to professional athletes, as PED use in adolescents has increased dramatically. Many professional organizations, including the American Academy of Orthopaedic Surgeons (AAOS), have taken a stance against PED use in sports. The AAOS believes neither anabolic steroids nor their precursors should be used to enhance performance or appearance, and that these substances should be banned in all sports programs. Pediatricians and orthopedists are often the first physicians to see these young athletes. It is critical for these physicians to recognize the significance of the problem, have the knowledge to inform adolescents, dissuade them from future use, and provide viable alternatives for meeting performance goals.


Journal of Bone and Joint Surgery, American Volume | 2014

The Effect of C-Arm Position on Radiation Exposure During Fixation of Pediatric Supracondylar Fractures of the Humerus

Raymond Y. Hsu; Craig R. Lareau; Jeom Soon Kim; Sarath Koruprolu; Christopher T. Born; Jonathan R. Schiller

BACKGROUND Closed reduction and percutaneous pinning of a pediatric supracondylar fracture of the humerus requires operating directly next to the C-arm to hold reduction and perform fixation under direct imaging. This study was designed to compare radiation exposure from two C-arm configurations: with the image intensifier serving as the operating surface, and with a radiolucent hand table serving as the operating surface and the image intensifier positioned above the table. METHODS We used a cadaveric specimen in this study to determine radiation exposure to the operative elbow and to the surgeon at the waist and neck levels during simulated closed reduction and percutaneous pinning of a pediatric supracondylar fracture of the humerus. Radiation exposure measurements were made (1) with the C-arm image intensifier serving as the operating surface, with the emitter positioned above the operative elbow; and (2) with the image intensifier positioned above a hand table, with the emitter below the table. RESULTS When the image intensifier was used as the operating surface, we noted 16% less scatter radiation at the waist level of the surgeon but 53% more neck-level scatter radiation compared with when the hand table was used as the operating surface and the image intensifier was positioned above the table. In terms of direct radiation exposure to the operative elbow, use of the image intensifier as the operating surface resulted in 21% more radiation exposure than from use of the other configuration. The direct radiation exposure was also more than two orders of magnitude greater than the neck and waist-level scatter radiation exposure. CONCLUSIONS Traditionally, there has been concern over increased radiation exposure when the C-arm image intensifier is used as an operating surface, with the emitter above, compared with when the image intensifier is positioned above the operating surface, with the emitter below. We determined that, although there was a statistically significant difference in radiation exposure between the two configurations, neither was safer than the other at all tested levels. CLINICAL RELEVANCE In contrast to traditional teaching regarding radiation exposure, neither C-arm configuration-with the image intensifier serving as the operating surface or with the image intensifier positioned above a radiolucent hand table-was shown to be clearly safer for pediatric supracondylar humeral fracture fixation.

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Amanda Weller

University of Pittsburgh

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Christine A. Ho

Texas Scottish Rite Hospital for Children

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Lawson A. Copley

Children's Medical Center of Dallas

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Richard Browne

Texas Scottish Rite Hospital for Children

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Sumeet Garg

Boston Children's Hospital

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