Christopher W. Reilly

Pediatric spine trauma.

The vast majority of spinal column and cord injuries that are sustained in North America occur in patients who are between the ages of fifteen and forty years. Children rarely have spinal injuries and even less frequently have spinal cord injuries. Patients who are younger than fifteen years of age account for fewer than 10% of patients who sustain spinal cord injuries1,2. The Canadian National Trauma Registry data reflect a similar conclusion: in 1998, there were twenty-eight spinal cord injuries nationally in children who were younger than fifteen years of age in comparison with 511 injuries reported for young adults from fifteen to forty years of age3. The base population-adjusted incidence suggests an annual pediatric spinal cord injury rate of 1 in 1,000,000, and an annual rate of young adult injury of 17 in 1,000,000. However, despite a lower frequency of injury, a number of features unique to pediatric patients demand specific attention. Children have different activity profiles, putting them at risk for different injury patterns (Fig. 1). Spinal column injuries are associated with a variety of injury mechanisms to which children are exposed, such as birth injuries, nonaccidental injuries, snowboarding, and tobogganing4-8. The most common causes of spinal injury in children are motor-vehicle collisions, falls, and sporting injuries9-11. Penetrating injuries are unusual in children. In addition, the growing spinal column has certain biomechanical features that result in specific injury patterns. Spinal cord injury without radiographic abnormality accounts for approximately one-third of all cord injuries in young children11,12. The great elasticity of the pediatric spinal column, the high head-to-body ratio in children, and the design of automobile restraint systems all play a role in the etiology of these injuries13,14 …

Prevalence of shoulder pain in adult- versus childhood-onset wheelchair users: A pilot study

Shoulder pain is a common overuse problem in long-term adult wheelchair users. The current study examined whether the prevalence of shoulder pain in adult wheelchair users who began using their wheelchairs during childhood (childhood-onset [CH-O] group) is similar to those who began using their wheelchairs as adults (adult-onset [AD-O] group). We compared 31 CH-O and 22 AD-O wheelchair users using the Wheelchair Users Shoulder Pain Index (WUSPI), an overall pain score (Brief Pain Inventory), and a lifestyle questionnaire to determine frequency and duration of physical activity. Shoulder pain (WUSPI) was greater in the AD-O wheelchair users compared with the CH-O group (p < 0.008), even though their general lifestyles were not different. The immature skeleton can possibly respond to the repetitive forces of wheeling better than that of those who begin using a wheelchair once their skeletal structure is completely developed.

Clinical usefulness of somatosensory evoked potentials for detection of brachial plexopathy secondary to malpositioning in scoliosis surgery.

Study Design. A retrospective longitudinal study of 434 consecutive pediatric patients who underwent surgical correction of scoliosis, while being monitored for positional brachial plexopathy. Objective. To evaluate the effectiveness of intermittent monitoring of ulnar nerve somatosensory evoked potentials (SSEPs) for detecting brachial plexus injury caused by malpositioning during scoliosis surgery. Summary of Background Data. Continuous intraoperative SSEP monitoring for spinal cord function has been well reported, and is widely accepted as the standard for spinal deformity correction surgery to detect and avoid neurologic injury. The use of SSEPs for the monitoring of ulnar nerve function intraoperatively as an indicator of brachial plexus function is becoming more accepted as a valid and useful technique to minimize intraoperative neurologic injuries during deformity corrections. Methods. A review was conducted to assess the effect of ulnar nerve SSEP monitoring, as a measure of brachial plexus function, during anterior, posterior, or combined approach surgeries. The type of scoliosis, type of surgery and positioning, and surgical event at noted amplitude decrease were included in an analysis of variance for repeated measures, and a Student t test was performed for significant differences. Results. A total of 27 patients had ulnar nerve amplitude decreases of ≥30%, resulting in a point prevalence of 6.2% for positional brachial plexopathy during positioning for all scoliosis surgeries. A significant difference was noted between the types of positioning, with prone positioning accounting for a higher rate of brachial plexopathy compared with anterior approach positioning (P < 0.01). No statistical difference exists as to the type of scoliosis present and the incidence of brachial plexopathy (P < 0.01). Conclusions. Avoidance of neurologic injury to the brachial plexus during scoliosis surgery is possible by early detection with ulnar nerve SSEP monitoring.

Evidence-based medicine analysis of all pedicle screw constructs in adolescent idiopathic scoliosis.

Study Design. Focus paper. Objective. To evaluate the current evidence-based medicine (EBM) literature in the use of pedicle screw constructs in patients with adolescent idiopathic scoliosis. Summary of Background. EBM has evolved over the past 20 years to provide a framework for the evaluation of therapy and the application of that assessment to a particular patient or a disease. Application of EBM analysis to spinal instrumentation, and specifically to pedicle screw constructs, is challenging. Methods. Cochrane database, Ovid Medline, and PubMed were searched using the terms “pedicle screws” and “adolescent idiopathic scoliosis.” The reference list of the major papers by authors Lenke, Suk, and Kim were hand searched. Relevant articles were retained if they described a pedicle screw construct to correct AIS or compared pedicle screw constructs with another technique. Articles that did not have patients with adolescent idiopathic scoliosis in their subject groups or did not use pedicle screws as a part of their deformity correction were excluded from the study. Results. Based on the search strategy described above, 40 articles met the inclusion criteria and were selected for review in this manuscript. Of these, 32 studies are retrospective reviews including 2 studies that do not define their data collection technique. Six studies have a prospective study design, 1 is a case report, and 1 is a cadaveric study. Conclusion. In the absence of evidence from randomized trials, surgeons must rely on the best available information to guide patient management decisions. Although there have been many publications on the topic of all pedicle screw constructs in AIS, evidence regarding the advantage of all pedicle screw constructs remain limited to case series, biomechanical studies, and expert opinions.

The effect of interbody cage positioning on lumbosacral vertebral endplate failure in compression.

Study Design. A biomechanical investigation using a human cadaver, multisegmental lumbosacral spine model. Objectives. To determine if 2 small, posterolaterally positioned titanium mesh interbody cages would provide superior construct strength and stiffness in compression compared to central cage placement. In addition, determine construct stiffness with interbody cages as opposed to an intact spine and assess the effect of bone mineral density (BMD). Summary of Background Data. Previous work has shown that the posterolateral corners of the lumbosacral endplates are stronger than the anterior and central regions. Information to suggest appropriate interbody cage positioning to avoid subsidence into adjacent vertebrae would be valuable for spine surgeons and implant designers. Methods. A total of 27 functional spinal units from L3 to S1 were dual x-ray absorptiometry scanned for BMD, instrumented with pedicle screw systems, and tested to failure in compression with titanium mesh interbody cages placed in 1 of 3 positions: 2 small posterolateral, 2 small central, or 1 large central. Analysis of covariance was conducted to compare failure load and stiffness across the different cage configurations. Repeated measures analysis of variance was used to analyze stiffness between functional spinal units with intact disc, discectomy, or interbody cages. Failure load was correlated against BMD. Results. Of the 3 placement patterns, 2 small titanium mesh cages in the posterolateral corners had 20% higher failure loads, although the difference was not significant (P = 0.20). Stiffness in compression for the 3 cage positions was not significantly different (P = 0.82). All intact discs with posterior instrumentation were significantly stiffer than any of the cage patterns (P = 0.0001). BMD of the vertebrae significantly correlated with failure loads (P = 0.007). Conclusions. The placement of 2 small interbody cages posterolaterally tended to result in higher failure loads than central cage placement, although the results were not statistically significant. It is noteworthy that cage placement in any position resulted in a less stiff construct in compression than with an intact disc.

Os odontoideum: a significant radiographic finding.

Os odontoideum can lead to instability of the atlantoaxial joint and places the spinal cord at significant risk for acute catastrophic events after minor trauma or chronic neurological change. We present two cases of os odontoideum in pediatric patients that were not appreciated at earlier remote imaging but were, in retrospect, detectable. One patient presented with an acute spinal cord injury. Incorporating assessment of dens integrity into the evaluation algorithm for all pediatric cervical spine studies should lead to early detection of os odontoideum lesions and allow referral to appropriate clinical spinal services for evaluation, surveillance and possible surgery to prevent future complications.

Publication of abstracts submitted to the annual meeting of the Pediatric Orthopaedic Society of North America: is there a difference between accepted versus rejected abstracts?

Purpose The purpose of this study was to determine publication rates of all abstracts submitted for presentation at the annual conference of the Pediatric Orthopaedic Society of North America (POSNA) comparing papers accepted for presentation with those that were not accepted and to determine the median times to publication and the mean impact factor of journals that published papers from the 2 groups. Methods The titles and authors of all abstracts submitted for presentation to the POSNA for the years 2003 to 2005 were identified. To determine publication status, we conducted a computerized Pubmed search using the first authors name. If multiple publications were identified, the Boolean search operator AND was used to combine author names with key words. The title of each located published article was compared with the title of the abstract. If differences were noted, the abstract content was compared with the final publication. The journals, impact factor was determined using the journal citation report. The median time from conference presentation to publication was determined using a Kaplan-Meier survival analysis. Results Of 1191 abstracts submitted to the annual meetings of POSNA from the years 2003 through 2005, 440 (37%) were accepted for presentation. Acceptance of submitted abstracts increased from 30% in 2003 to 40% in 2005. Of the 1191 abstracts 599 (50%) were subsequently published by August 2009. The mean publication rate for abstracts accepted for presentation was 58.9% (259 of 440) compared with 45% (339 of 751) for rejected abstracts. The median time to publication of accepted abstracts was not significantly different when compared with that of rejected abstracts. The mean journal impact factor for accepted articles was 2.2 compared with 1.5 for rejected abstracts. Conclusions The publication rates of abstracts submitted to POSNA is high compared with those of other international orthopaedic associations. The mean publication rate for accepted abstracts and rejected abstracts has increased substantially from 45% and 38% in 1991 to 1994 to 58.9% and 45% in 2003 to 2005, respectively. The journal in which most of the abstracts are ultimately published is the Journal of Pediatric Orthopaedics Mobility. Significance A significant proportion of abstracts not accepted for presentation at POSNA meetings are published in peer-reviewed journals. Nonacceptance of a study for presentation should not be a hindering factor for researchers in attempting to publish their study in peer-reviewed journals. Level of Evidence Not applicable.

Minimizing Tourniquet Pressure in Pediatric Anterior Cruciate Ligament Reconstructive Surgery : A Blinded, Prospective Randomized Controlled Trial

Background: Tourniquet cuff pressures in pediatric patients are commonly set at standard pressures. Recent evidence on adult subjects has shown that safer and more effective cuff pressures can be achieved by measuring limb occlusion pressure (LOP) and using a wide contour cuff. There is little evidence validating these techniques in children. The primary objective of this study was to evaluate if a difference in tourniquet cuff pressure can be achieved in a pediatric population using a wide contour cuff in conjunction with measured LOP when compared with a standard cuff and pressure. Methods: Subjects aged 10 to 17 years that underwent anterior cruciate ligament repair were included and randomized into either the control group or the experimental LOP group using variable block randomization. The tourniquet cuff was inflated to 300 mm Hg in the control group or to the recommended tourniquet pressure based on LOP measurement in the LOP group. The surgeon was blinded to cuff selection, application, and pressure throughout the surgical procedure. Immediately after the surgical procedure, the surgeon rated the quality of the bloodless field on a visual analog scale. This study was powered as an effectiveness trial, and intention to treat analysis was used. Results: After a planned interim analysis at midpoint, complete data were recorded for 11 (control group) and 10 (LOP group) patients. The quality of the surgical field was not different between the groups (P = 0.053). There was a statistically significant difference in the mean cuff pressure between the control (300 mm Hg) and the LOP (151 mm Hg) groups (P < 0.001). We ran the same analysis comparing the LOP data with the hypothetical control data of 250 mm Hg, and our results remained statistically significant (P < 0.001). Conclusions: The use of an automatic LOP measurement with the use of wide contour cuffs can significantly reduce mean tourniquet cuff pressures in pediatric patients compared with the typical practice of 300 or 250 mm Hg without compromising the quality of the surgical field. Level of Evidence: Level 1, prospective randomized controlled trial.

Is larger scoliosis curve magnitude associated with increased perioperative health-care resource utilization?: a multicenter analysis of 325 adolescent idiopathic scoliosis curves.

BACKGROUND The treatment of patients with large adolescent idiopathic scoliosis curves has been associated with increased surgical complexity. The purpose of this study was to determine whether surgical correction of larger adolescent idiopathic scoliosis curves increased the utilization of health-care resources and to identify potential predictors associated with increased perioperative health-care resource utilization. METHODS A nested cohort of patients with adolescent idiopathic scoliosis with Lenke type 1A and 1B curves were identified from a prospective longitudinal multicenter database. Four perioperative outcomes were selected as the primary health-care resource utilization outcomes of interest: operative time, number of vertebral levels instrumented, duration of hospitalization, and allogeneic blood transfusion. The effect of curve magnitude on these outcomes was assessed with use of univariate and multivariate regression. RESULTS Three hundred and twenty-five patients with a mean age of 15 ± 2 years were included. The mean main thoracic curve was 54.4° ± 7.8°. Larger curves were associated with longer operative time (p = 0.03), a greater number of vertebral levels instrumented (p = 0.0005), and the need for blood transfusion (with every 10° increase associated with 1.5 times higher odds of receiving a transfusion). In addition to curve magnitude, surgical center, bone graft method, and upper and lower instrumented levels were strong predictors of operative time (R2 = 0.76). The duration of hospitalization was influenced by the surgical center and intraoperative blood loss (R2 < 0.4), whereas the number of levels instrumented was influenced by the curve magnitude, curve correction percentage, upper instrumented vertebra, and surgical center (R2 = 0.64). CONCLUSIONS Correction of larger curves was associated with increased utilization of perioperative health-care resources, specifically longer operative time, a greater number of vertebral levels instrumented, and higher odds of receiving a blood transfusion.

The International Knee Documentation Committee Subjective Evaluation Form in a Preadolescent Population: Pilot Normative Data

Background The International Knee Documentation Committee Subjective Knee Evaluation Form is a knee-specific instrument composed of 18 questions. It is commonly used in adult and pediatric studies as a surgical outcome measure. Normative data exist for an adult population, but there have been no published normative results for younger subjects. Purpose To compile and report pilot normative International Knee Documentation Committee Subjective Knee Evaluation Form scores in a preadolescent population. Study Design Cross-sectional study; Level of evidence, 3. Methods The International Knee Documentation Committee Subjective Knee Evaluation Form was administered to 146 seventh-grade students (aged 12–14 years) at 2 local schools. The form was administered in its original format. Demographic and descriptive results were compiled. Results One hundred twenty-five completed responses were eligible for analysis. The mean age was 13.2 years (SD, 0.5; range, 12.2–14.2 years); 15% of participants had a history of knee injury or pain. The mean International Knee Documentation Committee score for all respondents was 89.4 (SD, 10.5; 95% confidence interval, 87.6–91.3; range, 52–100). Conclusion This study provides pilot normative data for mean International Knee Documentation Committee scores in a preadolescent population. The mean score in this younger cohort is consistent with normative data of adults age 35 years or younger. Although the International Knee Documentation Committee Subjective Knee Evaluation Form is often used in adolescent surgical studies, its validity in these populations remains to be established. Further work to establish the psychometric properties of the current form in younger age groups would be of significant benefit to clinicians.