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Dive into the research topics where Richard E. Bowen is active.

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Featured researches published by Richard E. Bowen.


Spine | 2010

Efficacy of intraoperative cell salvage systems in pediatric idiopathic scoliosis patients undergoing posterior spinal fusion with segmental spinal instrumentation.

Richard E. Bowen; Steven Gardner; Anthony A. Scaduto; Michael Eagan; Jason Beckstead

Study Design. Retrospective case–control study. Objective. Determine whether intraoperative cell salvage system use during pediatric posterior spinal fusion (PSF) with segmental spinal instrumentation for idiopathic scoliosis decreases intraoperative and perioperative (intraoperative plus postoperative) allogeneic blood transfusion. Summary of Background Data. Intraoperative cell salvage and reinfusion can reduce or obviate perioperative allogeneic blood transfusion. Despite these benefits, their efficacy in pediatric PSF is unclear. Reported complications include transient hematuria, altered hemostasis, and electrolyte imbalance. Methods. A total of 54 consecutive idiopathic scoliosis patients were studied: 21 non-cell saver and 33 cell saver patients. Data included age, body mass index, Cobb angle, perioperative hemoglobin levels, mean arterial pressure, surgical time, levels fused, perioperative estimated blood loss, and perioperative transfusions. A &khgr;2 and t tests were performed for intraoperative and perioperative allogeneic transfusion between groups. A regression analysis was performed between selected covariates and allogeneic transfusion. Relative risk analysis examined significant covariates regarding allogeneic transfusion rate. Results. Allogeneic transfusion rates were lower in the cell saver group (6% vs. 55% intraoperative and 18% vs. 55% perioperative, P < 0.05). Mean allogeneic transfusion volumes (mL/kg) were also lower (0.4 vs. 9.1 intraoperative and 1.9 vs. 11.1 perioperative, P < 0.05). Multivariate analysis confirmed these differences were independent of perioperative blood loss, and also demonstrated that surgical time and blood loss were significantly related to allogeneic transfusion volume. The allogeneic transfusion relative risk was 2.04 in patients with surgery >6 hours and 5.87 in patients not receiving cell saver blood. All patients with surgeries >6 hours and estimated blood loss >30% of total blood volume received cell saver system blood. Conclusion. Cell saver use decreased allogeneic transfusion, particularly in surgeries >6 hours with estimated blood loss >30% of total blood volume. This study confirms the utility of routine cell saver use during PSF with segmental spinal instrumentation for idiopathic scoliosis.


Gait & Posture | 2011

Influence of gait analysis on decision-making for lower extremity orthopaedic surgery: Baseline data from a randomized controlled trial §

Tishya A. L. Wren; Norman Y. Otsuka; Richard E. Bowen; Anthony A. Scaduto; Linda S. Chan; Minya Sheng; Reiko Hara; Robert M. Kay

Previous studies examining the influence of gait analysis on surgical decision-making have been limited by the lack of a control group. The aim of this study was to use data from a randomized controlled trial to determine the effects of gait analysis on surgical decision-making in children with cerebral palsy (CP). 178 ambulatory children with CP (110 male; age 10.3±3.8 years) being considered for lower extremity orthopaedic surgery underwent gait analysis and were randomized into one of two groups: gait report group (N=90), where the orthopaedic surgeon received the gait analysis report, and control group (N=88), where the surgeon did not receive the gait report. Data regarding specific surgeries were recorded by the treating surgeon before gait analysis, by the gait laboratory surgeon after gait analysis, and after surgery. Agreement between the treatment done and the gait analysis recommendations was compared between groups using the 2-sided Fishers Exact test. When a procedure was planned initially and also recommended by gait analysis, it was performed more often in the gait report group (91% vs. 70%, p<0.001). When the gait laboratory recommended against a planned procedure, the plan was changed more frequently in the gait report group (48% vs. 27%, p=0.009). When the gait laboratory recommended adding a procedure, it was added more frequently in the gait report group (12% vs. 7%, p=0.037). These results provide a stronger level of evidence demonstrating that gait analysis changes treatment decision-making and also reinforces decision-making when it agrees with the surgeons original plan.


Journal of Pediatric Orthopaedics | 2006

Body mass index and Blount disease

Marinis Pirpiris; Kent R. Jackson; Eugene Farng; Richard E. Bowen; Norman Y. Otsuka

Abstract: As the increasing prevalence of overweight and obese children is approaching epidemic proportions in North America, this study was designed to investigate whether Body Mass Index (BMI) and age- and gender-specific percentile Body Mass Index (BMI %) are associated with the likelihood of being listed for surgery for Blount disease after initial presentation to a tertiary referral centre. In a restrospective consecutive sample of 102 children with an average age of 5.9 ± 4.3 years, it was determined that there was a significant association between BMI and BMI% and being listed for surgery, after adjusting for the effects of the childs age and gender, with mean odds ratios of 1.30 (95% confidence interval 1.02-1.60) and 1.05 (95% confidence interval 1.01-1.09) respectively. When the sample was subgrouped into infantile (less than 3 years of age) and late-onset (greater than 3 years of age), BMI and BMI% were still significantly associated with the children being listed for surgery in the late-onset group with mean odds ratios 2.75 (95% confidence interval 1.03-7.33) and 1.09 (95% confidence interval 1.01-1.18) respectively. However, of the two measures only the BMI was significant in the infantile group with an odds ratio of 1.27 (95% confidence interval 1.01-1.60). Should these associations be real then measures aimed at decreasing weight in children may have some effect on the number of children undergoing surgery for the treatment of Blount disease.


Gait & Posture | 2013

Outcomes of lower extremity orthopedic surgery in ambulatory children with cerebral palsy with and without gait analysis: Results of a randomized controlled trial

Tishya A. L. Wren; Norman Y. Otsuka; Richard E. Bowen; Anthony A. Scaduto; Linda S. Chan; Sandra W. Dennis; Susan A. Rethlefsen; Bitte S. Healy; Reiko Hara; Minya Sheng; Robert M. Kay

This study examined the impact of gait analysis on surgical outcomes in ambulatory children with cerebral palsy (CP) through a randomized controlled trial. 156 children with CP (94 male; age 10.2 ± 3.7 years) underwent gait analysis and were randomized to two groups: Gait Report group (N = 83), where the referring surgeon received the patients gait analysis report, and Control group (N = 73), where the surgeon did not receive the gait report. Outcomes were assessed pre- and 1.3 ± 0.5 years post-operatively. An intent-to-treat analysis compared outcomes between the two groups. Outcome measures included the Gillette Functional Activity Questionnaire (FAQ), Gait Deviation Index (GDI), oxygen cost, gross motor function measure, Child Health Questionnaire (CHQ), Pediatric Outcomes Data Collection Instrument (PODCI), and Pediatric Evaluation and Disability Inventory. The outcomes that differed significantly between groups were change in health from the CHQ, which was rated as much better for 56% (46/82) of children in the Gait Report group compared with 38% (28/73) in the Control group (p = 0.04), and upper extremity physical function from the PODCI. Gait outcomes (FAQ and GDI) improved more when over half of the recommendations for a patient were followed or the recommended extent of surgery (none, single, or multi-level) was done (p ≤ 0.04). On average, however, only 42% of the recommendations were followed in the Gait Report group, compared with 35% in the Control group (p = 0.23). This is much less than the >85% reported in previous studies and may account for the lack of differences between groups for some of the outcome measures.


Spine deformity | 2013

Quantification of Increase in Three-dimensional Spine Flexibility Following Sequential Ponte Osteotomies in a Cadaveric Model

Sophia N. Sangiorgio; Sean L. Borkowski; Richard E. Bowen; Anthony A. Scaduto; Nathan L. Frost; Edward Ebramzadeh

BACKGROUND Posterior-only procedures are becoming more popular for treatment of rigid adolescent idiopathic scoliosis, but little is known about the quantitative correction potential for Ponte osteotomies. The objective of this study was to quantify and compare the range of motion of intact multilevel thoracic spine segments with the same segments after each of 3 sequential Ponte osteotomies. METHODS We tested 5 human cadaveric thoracic spine segments, spanning T-T6, or T7-T12, in an 8-degree-of-freedom servo-hydraulic load frame, monitoring motion of each vertebra with an optical motion tracker. We measured range of motion while we applied cyclic, pure moment loading to produce flexion-extension, lateral bending, and axial rotation at a rate of 0.5°/second, to a maximum of ± 6 Nm. Each specimen was tested intact and after each of 3 sequential Ponte osteotomies. RESULTS Total range of motion for the segments (either T2-T5 or T8-T11) increased by as much as 1.6° in flexion, 1.5° in extension, 0.5° in lateral bending, and 2.8° in axial rotation with each osteotomy. Because of the variation in initial specimen stiffness, we normalized motions to the intact values. In flexion, average range of motion increased after each osteotomy compared with intact, by 33%, 56%, and 69%. In extension, slightly smaller increases were seen, increasing by as much as 56% after the third osteotomy. In lateral bending, Ponte osteotomies had little effect on range of motion. In axial rotation, range of motion increased by 16%, 29%, and 65% after 3 osteotomies. CONCLUSIONS Sequential Ponte osteotomies increased range of motion in flexion, extension, and axial rotation, but not in lateral bending. These results suggest that the Ponte osteotomy may be appropriate when using derotational correction maneuvers, or to improve apical lordosis at the apex of curvature during posterior spinal fusion procedures. Although these techniques are effective in gaining correction for kyphotic deformities and rigid curvatures, they add time and blood loss to the procedure.


Journal of Pediatric Orthopaedics | 2003

Outcome of slipped capital femoral epiphysis in renal osteodystrophy

William L. Oppenheim; Richard E. Bowen; Paul W. Mcdonough; Tadashi T. Funahashi; Isidro B. Salusky

The cases of renal osteodystrophy-associated slipped capital femoral epiphysis in 11 consecutive patients were reviewed. Nine patients had bilateral involvement, totaling 20 hips. The mean age at presentation was 10.6 years. Slip location was physeal in 13 and metaphyseal in seven hips. All patients had prompt medical treatment of their bone disease, and nine patients underwent surgical stabilization. Fixation consisted of multiple custom-machined Steinmann pins that were smoothed distally but threaded proximally, allowing continued proximal femoral growth. The mean radiographic and clinical follow-up was 5.7 years and 9.1 years, respectively. Slips stabilized in 14 of 16 operated hips (88%), whereas one patient with inadequate renal disease control had slip progression requiring subsequent subtotal parathyroidectomy and repeat fixation. Combined medical management and surgery with custom-machined pins prevented slip progression while allowing continued physeal growth.


Journal of Shoulder and Elbow Surgery | 1996

Complications of type I coronoid fractures in competitive athletes: Report of two cases and review of the literature

Stephen H. Liu; Mark H. Henry; Richard E. Bowen

Coronoid fractures have been classified into three types. Elbow instability is a well-recognized complication of type III and less so in type II fractures. Type I fractures have generally been considered to heal uneventfully, with early range of motion. We present two cases of type I fractures in athletes that failed to improve with conservative management. One developed loose body formation and the other a fibrous nonunion with mechanical blockage of elbow flexion. Both patients responded to arthroscopic intervention and returned to full athletic activities. These cases illustrate potential complications with type I coronoid fractures in competitive athletes that should be recognized and treated early.


Journal of Pediatric Orthopaedics | 2008

Concurrent and discriminant validity of Spanish language instruments for measuring functional health status.

Tishya A. L. Wren; Minya Sheng; Richard E. Bowen; Anthony A. Scaduto; Robert M. Kay; Norman Y. Otsuka; Reiko Hara; Linda S. Chan

Background: Questionnaires translated into languages other than English are often not validated to the same extent as the English versions. This study examined the concurrent and discriminant validity of selected domains related to physical function from Spanish language versions of the Child Health Questionnaire (CHQ), Pediatric Outcomes Data Collection Instrument (PODCI), and Pediatric Evaluation and Disability Inventory (PEDI). Methods: Concurrent validity was examined in 93 children with cerebral palsy by correlating questionnaire domain scores with Gross Motor Function Measure and Gillette Functional Assessment Questionnaire walking scale scores. Discriminant validity with respect to Gross Motor Function Classification System (GMFCS) level was examined using analysis of variance and nonparametric discriminant analysis. Results: Concurrent validity was demonstrated for 3 domains from the PEDI (Mobility functional skills, &tgr; = 0.62; Mobility caregiver assistance, &tgr; = 0.46-0.55; and Self-care functional skills, &tgr; = 0.30-0.36), 3 domains from the PODCI (Sports and physical function, &tgr; = 0.48-0.51; Transfer and basic mobility, &tgr; = 0.48-0.51; and Upper extremity physical function, &tgr; = 0.28), and 1 domain from the CHQ (Physical function, &tgr; = 0.31-0.36). Discriminant validity was demonstrated for the same domains based on significant decreases in domain scores with increasing GMFCS level. Discriminant validity was highest for the PODCI, which correctly classified 98% (91/93) of subjects into the correct GMFCS level when all 3 domains were considered. Conclusions: For the first time, concurrent validity and discriminant validity have been demonstrated for the physical function domains of Spanish language versions of the PODCI, PEDI, and CHQ questionnaires. PODCI and PEDI had the highest concurrent validity, and PODCI had the best discriminant ability. Clinical Relevance: It is important to examine the validity of instruments when they have been translated from English into other languages. This importance will only increase as the population of non-English-speaking patients expands.


Journal of Pediatric Orthopaedics | 2002

Relative tibial and femoral varus as a predictor of progression of varus deformities of the lower limbs in young children.

Richard E. Bowen; Frederick J. Dorey; Colin F. Moseley

Many young children present to pediatric orthopaedic surgeons with genu varum and mild beaking of the medial metaphysis on x-ray. Predicting whether these deformities will progress is challenging. In addition, there is no consensus as to whether these children should all be classified as having Blount disease. To avoid this latter problem, the authors included in this study all children presenting with bowed legs, regardless of diagnosis. With the aim of improving the ability to predict progression, the authors tested the hypothesis that patients with progression have more tibial than femoral varus. The authors reviewed 173 varus limbs of 98 patients younger than 4 years old. The authors determined the angular deformity in both femur and tibia by measuring the angles between their mechanical axes and the transverse axis of the knee, and determined the contribution of tibial deformity as a percentage of the total (%DT). The metaphyseal–diaphyseal angles of the tibia (MDA) were also measured to compare the value of that test with the %DT. There were 22 limbs with progressive and 141 limbs with resolving varus. Both the MDA and %DT were significantly different between groups. Tibial varus was found to exceed femoral varus in all patients with progression and also in several patients whose deformity resolved spontaneously. Although more specific and more sensitive than the MDA, the %DT is a good, but not perfect, predictor of progression. However, all patients in this series with both a %DT >50% and an MDA of 16° or greater went on to progress. Using both of these tests together may therefore provide the surgeon with a reliable indicator of the children who would benefit from surgical correction.


Journal of Pediatric Orthopaedics | 2012

Outcome assessment in neuromuscular spinal deformity.

Richard E. Bowen; Mark F. Abel; Vincent Arlet; Desmond Brown; Douglas C. Burton; Phyllis D’Ambra; Laura Gill; Dale V. Hoekstra; Lawrence I. Karlin; James Raso; James O. Sanders; Frank J. Schwab

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.

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Linda S. Chan

University of Southern California

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Minya Sheng

Children's Hospital Los Angeles

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Reiko Hara

Children's Hospital Los Angeles

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Robert M. Kay

University of Southern California

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