Radiographic and Respiratory Effects of Growing Rods in Children With Spinal Muscular Atrophy.

BACKGROUND: Respiratory weakness and spinal deformity are common in patients with spinal muscular atrophy (SMA). Posterior (distraction type) growing rods have recently gained favor as a treatment option in this population, due to their ability to prevent spinal deformity progression and their potential to allow lung volumes to increase over time. The objective of this study was to determine the impact of posterior growing rods on the spinal alignment and respiratory function in children with SMA with intermediate term follow-up. METHODS: A single center, retrospective review was performed on SMA patients treated with growing rods, inserted between 2004 and 2010, with a minimum of 2-year follow-up. SMA type, changes in the route of bi-level positive airway pressure respiratory support and the amount of time receiving respiratory support are reported. Pulmonary function tests (PFTs) and radiographs were reviewed and data evaluated preinsertion, postinsertion, and at latest follow-up. RESULTS: Sixteen children with SMA (5 type I, 11 type II) met inclusion criteria. The average age of insertion was 5.8 (±1.5) years, the median number of lengthenings was 4 (range, 3 to 5), and the median time between insertion and last clinical review was 4.7 (range, 2.7 to 9.5) years. Radiographic review demonstrated significant (P<0.05) improvements in the following: Spinal curve magnitude, pelvic obliquity, space available for the lung, rib vertebral angle difference, and thoracic kyphosis following growing rod implantation. Thoracic and lumbar height and chest width and depth increased significantly (P<0.05) over the lengthening process. None of the patients initially required more than noninvasive positive pressure ventilation support. Fifteen of the 16 experienced no changes in their noninvasive positive pressure ventilation support needs throughout the study duration, requiring support only at night and naps. Serial PFTs were available for 6 children with SMA type II. PFTs demonstrated significant improvements in absolute forced vital capacity (FVC), minimal changes in the maximal inspiratory and expiratory pressures, and a gradual worsening of percent predicted FVC. CONCLUSIONS: Clinical respiratory support requirements appear to stabilize following the insertion and lengthening of posterior based growing rods in the SMA population. Similar to previous studies, increased spinal height and thoracic cavity size were noted throughout the process. Despite an increasing absolute FVC, the percent predicted FVC diminished over time. LEVEL OF EVIDENCE: Level IV-therapeutic.

Reliability of radiographic measures in infants with clubfoot treated with the Ponseti method.

PURPOSE: The aim of this study was two-fold: (1) to determine if radiographic measures can be reliably made in infants being treated with the Ponseti method and (2) to document radiographic changes before and after Achilles tenotomy. METHODS: A retrospective radiographic and chart review was performed on children with clubfoot treated by the Ponseti method at a single institution over a 10-year period. Five independent reviewers measured a series of angles from a lateral forced dorsiflexion radiograph taken prior to and following Achilles tenotomy. These measures were taken in triplicate to determine the intra- and inter-reader reliability of dorsiflexion, tibio-calcaneal, talo-calcaneal, and talo-first metatarsal angles. RESULTS: Thirty-six subjects (56 feet) were treated with the Ponseti method and met the inclusion criteria. The median (range) age of patients at the time of tenotomy was 52 (34-147) days. The intra-reader reliability [intra-rater correlation coefficient (ICC)] for each of the measured angles pre- and post-tenotomy ranged from 0.933 to 0.995 and 0.864 to 0.995, respectively. Similarly, the inter-reader reliabilities (ICC) ranged from 0.727 for the pre-tenotomy (talo-calcaneal) to 0.950 for the post-tenotomy (talo-first metatarsal) angles. The mean differences between pre- and post-tenotomy radiographs were: dorsiflexion increase of 17°, tibio-calcaneal angle increase of 19°, talo-calcaneal angle increase of 9°, and talo-first metatarsal angle increase of 10° (p-value ≤0.001 for all measurements except the talo-first metatarsal angle, with a p-value of 0.001). CONCLUSIONS: Reliable radiographic measures can be made from lateral dorsiflexion radiographs of clubfeet treated with the Ponseti method before and after Achilles tenotomy.

Cast-saw injuries: assessing blade-to-skin contact during cast removal. Does experience or education matter?

BACKGROUND: Cast-saw injuries are sustained during cast removal or splitting of a cast when a hot cast-saw blade touches the patient's skin inadvertently during cast removal. Other studies have evaluated risk factors associated with saw-blade temperature, however, none have documented the number and duration of blade-to-skin contacts during cast removal. METHODS: Using a pediatric long-arm model capable of detecting cast-saw blade contact, we tested the ability of health care providers to apply and remove casts before and after a brief education module. The total number and duration of "touches" between the saw and the model's "skin" were recorded. Correlations between user "touches," and experience and comparisons between pre- and post-education "touches" were performed. RESULTS: Of the 18 study participants, 16 touched the model surface with the cast saw; 7 of the 18 participants maintained blade contact with the skin for > 1 second 22 times during the testing process. Participants with less experience averaged 20 (± 16) touches, whereas more experienced participants averaged 24 (± 19) touches (P = 0.7). Average number of touches was similar-before 22 (± 20) and after 25 (± 22); P = 0.5-participants completed an education module. No correlation between experience or participation in the education program was found with decreased number of blade-to-skin touches. CONCLUSION: Nearly all clinicians inadvertently contacted the underlying skin with the cast-saw blade. In our limited sample size, experience and education did not prevent this; therefore, minimizing time of contact and blade temperature may be more important factors in minimizing cast-saw injuries.

Comparing results of posterior spine fusion in patients with AIS: Are two surgeons better than one?

AIMS: Spinal deformity surgery is one of the most complicated procedures performed in pediatric orthopedics. These surgeries can account for long operative times and blood losses. Finding ways to limit patient morbidity undergoing these procedures may benefit many. We hypothesized that utilizing two fellowship trained pediatric spinal deformity surgeons would lead to decreased operative time and blood loss when compared with single surgeon. We felt very little difference would be found in terms of curve correction. METHODS: A retrospective review of spinal deformity surgeries performed at two institutions was performed. At one institution, the standard of care was to have two fellowship deformity trained surgeons perform all deformity surgeries simultaneously, while at the second institution posterior spinal fusions performed by individual surgeons were performed. The single surgeon cohort was further divided based on instrumentation type (pedicle screw vs hybrid constructs). Cases for this review were limited to posterior spinal fusions without osteotomies in patients with idiopathic or idiopathic like curves. Cohorts were compared pre-operatively for age at surgery, sex, BMI, largest Cobb angle. Intra-operative comparisons included total EBL, instrumentation type screws vs hybrid, levels fused, and operative time. Comparisons between largest remaining Cobb, EBL/level, time/level, lowest recorded Hb, allogenic transfusion requirements, length of PICU stay, and total length of hospital stay were then made. Pair-wise student t-tests was performed between cohorts with significance defined as a p-value of 0.05 or less. CONCLUSIONS: Twenty-four patients were found in the (BMP) cohort, where as eighty-two were found in the control group. No significant difference in age, sex, starting hemoglobin, BMI*, or maximum pre-operative Cobb between cohorts was found. A significantly lower number of levels were fused in the BMP cohort than the control (9 ± 2 vs 11 ± 2) p < 0.001, and likewise a significantly shorter operative time (average >2 h) was seen in the BMP cohort. Interestingly, no difference in estimated blood loss, blood loss/level fused, operative time/level fused was observed, yet a significantly greater drop in hemoglobin (average 1 g) p = 0.001 and allogenic transfusion rate was seen in the control group (4% (1/24) vs 29% (24/82)) p = 0.01. A greater improvement in Cobb angle was seen in the BMP group 46 ± 8 vs 35 ± 10° p < 0.001. No differences were seen in nights in the PICU and peri-operative complications, however patients in the BMP averaged nearly 1day less in the hospital than in the control group. Utilizing a blood management program including two surgeons in spinal deformity surgery appears to decrease operative time, blood loss, and improve curve correction. Confounding factors such as differences in number of fusion levels, curve types, instrumentation type, and institutional practices prevents drawing definitive conclusions. This is the first study to show potential benefits of utilizing a blood management program with dual surgeons in spinal deformity cases.

Relationships among specific viral pathogens, virus-induced interleukin-8, and respiratory symptoms in infancy.

Both virus-mediated damage to airway tissues and induction of pro-inflammatory cytokines such as interleukin-8 (IL-8) could contribute to symptom severity during viral respiratory infections in children. To test the hypothesis that IL-8 contributes to the pathogenesis of respiratory symptoms during naturally acquired respiratory viral infections in children, nasal wash samples collected from infants with acute viral infections (n = 198) or from healthy uninfected infants (n = 31) were analysed for IL-8. Nasal wash IL-8 was positively related to age in uninfected children (rs = 0.36, p < 0.05). Respiratory syncytial virus (RSV) infection caused more severe respiratory symptoms compared to infections with influenza A, parainfluenza viruses, or rhinoviruses. In addition, RSV, parainfluenza and rhinovirus infections increased levels of IL-8 in nasal lavage fluid, and there were some differences in the ability of the viruses to induce IL-8 production (RSV>influenza, p < 0.05). Finally, there were significant correlations between nasal wash IL-8 levels and symptom scores during infections with rhinovirus (rs = 0.56, p < 0.001) or influenza A (rs = 0.45, p < 0.05), but not with parainfluenza virus or RSV. These findings provide evidence of a close relationship between the generation of IL-8 and symptoms during acute community-acquired infections with rhinovirus or influenza A. In contrast, for RSV and parainfluenza infections, factors in addition to IL-8 production appear to contribute to the generation of clinical symptoms.