Vincent F. Deeney

Effects on lung function of multiple expansion thoracoplasty in children with thoracic insufficiency syndrome: a longitudinal study.

Study Design. Longitudinal study of intraoperative pulmonary function in young children with thoracic hypoplasia and scoliosis undergoing multiple expansion thoracoplasty using the vertical expandable prosthetic titanium ribs (VEPTRs). Objective. To test the long-term efficacy of VEPTR multiple expansion thoracoplasty. Summary of Background Data. To our knowledge, no direct measurements of pulmonary function have been reported with VEPTR expansion thoracoplasty. Methods. There were 10 children with thoracic insufficiency syndrome, secondary to thoracic hypoplasia with progressive scoliosis, studied. A mobile pulmonary function laboratory unit was used to study forced vital capacity (FVC), maximum expiratory flow volume curves, and respiratory system compliance (Crs) with the patient under general anesthesia immediately before and after expansion thoracoplasty. Studies were repeated every 6 months at each subsequent operation for expansion thoracoplasty for the duration up to 33 months. Results. At the baseline studies, FVC showed a moderate-to-severe decrease (69% of predicted values), indicating the presence of significant restrictive lung defect. Only 1 of 10 children had severe airway obstruction. The baseline Crs was markedly decreased in part because of the presence of significant atelectasis. Crs increased with an average of 42% after repeated hyperinflation (deep sighs). There was no change in lung volume or function immediately before versus after completion of expansion thoracoplasty. FVC increased significantly over time, with an average rate of 26.8% per year, the rate of increase similar to that of healthy children of comparative ages. In terms of percent-predicted values, FVC did not change significantly between the baseline and last test, indicating that in most children studied, lung growth kept up with body growth. Conclusion. Although it is difficult to assess the extent of the efficacy without a proper or historical control group for comparison, the present study indicates that in children with severe thoracic insufficiency syndrome, the insertion of VEPTRs with multiple expansion thoracoplasties is beneficial over time, by allowing the lungs to expand with body growth without further deterioration in lung function.

Thoracic malformation with early-onset scoliosis: Effect of serial VEPTR expansion thoracoplasty on lung growth and function in children

The effect on pulmonary function of serial VEPTR expansion thoracoplasty was studied longitudinally in anesthetized children with spondylothoracic dysplasia using a special mobile unit. The median age of 24 children at the start of surgery was 4.6 years (1.8-10.8) and most exhibited a moderate-to-severe restrictive lung defect. After a median of 3.2 years (1.0-6.5), their forced vital capacity (FVC) was found to have increased by an average of 11.1%/year. The rate of increase was greater in children who were younger than 6 years at the start of the study than in older children (14.5% versus 6.5%, p<0.01). The average specific respiratory system compliance (C(rs)) was mildly-to-moderately decreased at the start, and over the study it decreased on average to 56% of the initial value in spite of clinically successful expansion thoracoplasty and lung growth, indicating increasing stiffness of the thorax with growth.

Spica cast application in the emergency room for select pediatric femur fractures.

Objectives: This study was designed to evaluate the efficacy and safety of immediate spica casting in the emergency room (ER) and evaluate the effect of discharge from the emergency room on short- term complications. Design: Retrospective review of patients treated with immediate spica casting in the ER between June 1, 1993 and July 30, 2001. Setting: Major, pediatric, orthopaedic trauma and referral center. Patients: A total of 145 pediatric femur fractures in children, younger than age 7 years, treated with immediate spica casting in the ER were reviewed to determine radiographic outcome and short-term complication rates. Intervention: All patients underwent immediate spica cast placement in the ER under conscious sedation. Patients meeting specific criteria were discharged immediately from the ER. Main Outcome Measurements: Radiographic acceptability of alignment at fracture union (angulation, shortening), loss of reduction, number of return visits to the emergency room, and clinical outcome at final follow-up. Results: Average follow-up was 20 ± 16 weeks (range, 1-9 months). Forty-eight patients (33%) were discharged from the ER. No clinical complications were noted at last follow-up. All children younger than age 2 years, and 86.5% of children ages 2 to 5 years, met acceptable malalignment parameters on final radiographs. There were 16 ER visits (11%) for cast problems. Rereduction in the operating room was needed in 11 patients (8.9%); 6.9% of patients had a cast problem noted during follow-up visits. Only 9% of patients developed a major complication. Initial shortening was the only independent risk factor found to be associated with loss of reduction. Admission status had no significant effect on the number of ER visits or development of a complication. Conclusions: If there are no associated factors requiring admission (ie, child abuse or polytrauma), spica casting in the ER for pediatric femur fractures followed by immediate discharge can be safely performed with a low complication rate in children younger than age 6 years, nearly eliminating the need for general anesthesia.

Somatosensory-evoked potential monitoring during instrumented scoliosis corrective procedures: validity revisited

BACKGROUND Intraoperative monitoring (IOM) using somatosensory-evoked potentials (SSEPs) plays an important role in reducing iatrogenic neurologic deficits during corrective pediatric idiopathic procedures for scoliosis. However, for unknown reasons, recent reports have cited that the sensitivity of SSEPs to detect neurologic deficits has decreased, in some to be less than 50%. This current trend, which is coincident with the addition of transcranial motor-evoked potentials, is surprising given that SSEPs are robust, reproducible responses that were previously shown to have sensitivity and specificity of >90%. PURPOSE Our primary aim was to assess whether SSEPs alone can detect impending neurologic deficits with similar sensitivity and specificity as originally reported. Our secondary aim was to estimate the potential predictive value of adding transcranial motor-evoked potentials to SSEP monitoring in idiopathic scoliosis procedures. DESIGN This was a retrospective review to analyze the efficacy of SSEP monitoring in the group of pediatric instrumented scoliosis fusion cases. PATIENT SAMPLE We retrospectively reviewed all consecutive cases of patients who underwent idiopathic scoliosis surgery between 1999 and 2009 at Childrens Hospital of Pittsburgh. We identified 477 patients who had the surgery with SSEP monitoring alone. Exclusion criteria included any patients with neuromuscular disorders or unreliable SSEP monitoring. Patients who had incomplete neurophysiology data or incomplete postoperative records were also excluded. OUTCOME MEASURES Major outcomes measured were clinically significant postoperative sensory or motor deficits, as well as significant intraoperative SSEP changes. METHODS Continuous interleaved upper- and lower-extremity SSEPs were obtained throughout the duration of all procedures. We considered a persistent 50% reduction in primary somatosensory cortical amplitude or a prolongation of response latency by >10% from baseline to be significant. Persistent changes represent significant deviation in SSEP amplitude or latency in more than two consecutive averaged trials. Patients were classified into one of four categories with respect to SSEP monitoring: true positive, false positive, true negative, and false negative. The sensitivity, specificity, positive predictive value, and negative predictive value were then calculated accordingly. RESULTS Our review of 477 idiopathic scoliosis surgeries monitored using SSEPs alone revealed a new deficit rate of 0.63% with no cases of permanent injury. Sensitivity = 95.0%, specificity = 99.8%, positive predictive value = 95%, negative predictive value = 99.8%. Using evidence-based epidemiologic measures, we calculated that the number needed to treat was 1,587 patients for one intervention to be performed that would have been missed by SSEP monitoring alone. In addition, the number needed to harm, which represents the increase in false positives with the addition of transcranial electrical motor-evoked potentials, was 200. CONCLUSION SSEP monitoring alone during idiopathic scoliosis continues to be a highly reliable method for the detection and prevention of iatrogenic injury. Our results confirm the high sensitivity and specificity of SSEP monitoring alone published in earlier literature. As such, we suggest the continued use of SSEP alone in idiopathic scoliosis surgeries. At this time we do not believe there are sufficient data to support the addition of MEP monitoring, although more studies and revised criteria for the use of MEP may provide added value for its use in the future.

Ulnar nerve injury after closed forearm fractures in children

We treated two children with the unusual complication of ulnar nerve palsy after closed both-bone forearm fractures. Both patients developed an ulnar claw-hand deformity within 7 weeks of injury that resolved spontaneously by 20 weeks postinjury with nonoperative treatment. No patient showed any signs or symptoms of an ischemic compartment syndrome. Both nerve injuries were identified immediately at the time of fracture by a careful neurologic examination. This avoids confusion with a postreduction nerve entrapment injury or ischemic injury after a localized compartment syndrome, which may have considerably different treatments and outcomes. We recommend that a careful neurologic examination be recorded before any manipulative reduction of forearm fractures in children. If an ulnar nerve palsy is detected, it is probably a result of nerve contusion and should resolve without the need for surgical exploration.

Pulmonary and Radiographic Outcomes of VEPTR (Vertical Expandable Prosthetic Titanium Rib) Treatment in Early-Onset Scoliosis

BACKGROUND VEPTR (vertical expandable prosthetic titanium rib) expansion thoracoplasty is used to manage thoracic insufficiency syndrome in early-onset scoliosis. Literature regarding the effects of this technique on pulmonary function is scarce. The aim of this study was to report the intermediate-term results of VEPTR expansion thoracoplasty. METHODS Twenty-one children with thoracic insufficiency syndrome underwent VEPTR expansion thoracoplasty from 2002 to 2012 and had complete chart data, preoperative and follow-up radiographs, and pulmonary function tests performed at the index implantation, first expansion, and last expansion. Pulmonary function tests with forced and passive deflation techniques developed for children under general anesthesia were performed prior to the index implantation and each expansion surgery under the same anesthetic conditions. Pulmonary and radiographic parameters were analyzed longitudinally. RESULTS Mean follow-up was six years, and mean age at implantation was 4.8 years. The mean number of expansion procedures per patient was eleven, and the mean number of pulmonary function tests was ten. The mean interval between surgical procedures was 6.4 months. Mean forced vital capacity (FVC) increased from 0.65 to 0.96 L (p < 0.0001). However, the percentage of the predicted FVC decreased from 77% to 58%. Respiratory system compliance normalized on the basis of body weight, Crs/kg, decreased by 39%, from 1.4 to 0.86 mL/cm H2O/kg. The mean Cobb angle before treatment was 80°, and the mean maximum thoracic kyphosis angle was 57° (range, 7° to 107°). The initial coronal correction was maintained at the time of final follow-up (67°); however, there was a trend toward a decrease in the maximum thoracic kyphosis angle (to 66°, p = 0.08). Clinically apparent proximal thoracic kyphosis occurred in four patients, and spinal imbalance occurred in seven. The mean gain in T1-T12 height during the treatment period was 18 mm (2.9 mm/year). CONCLUSIONS FVC improved over time; however, this increase in lung volume did not keep up with the growth of the child, as the percentage of the predicted FVC decreased, and the chest wall stiffness increased. Coronal correction was maintained, but the increase in proximal thoracic kyphosis is concerning. LEVEL OF EVIDENCE Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Pseudo-Volkmann's contracture due to tethering of flexor digitorum profundus to fractures of the ulna in children.

We studied seven children with the unusual complication of pseudo-Volkmanns contracture due to tethering of the flexor digitorum profundus to fractures of the ulna. It was detected 2 days to 16 years after closed reductions of fractures of the shafts of the radius and ulna. The children did not have nerve palsies or undue pain after the reductions. Normal length, excursion, and function of the flexor digitorum profundus was restored by untethering the muscle and its tendons from the ulnar fracture by early manipulation or by late localized myotenolysis. We recommend that the passive range of motion of all fingers be routinely checked immediately after closed reductions of fractures of the radius and ulna. If muscle tethering is detected, the fracture is remanipulated to release the muscle. If the muscle is still tethered, then surgical release, through a small incision, is required.

VEPTR to treat nonsyndromic congenital scoliosis: a multicenter, mid-term follow-up study.

Background: Traditional surgical management of multiple congenital vertebral anomalies in young children, including fusion in situ and hemiepiphyseodesis, do not promote spinal growth nor address the associated thoracic insufficiency syndrome. We hypothesize that vertical expandable prosthetic titanium rib (VEPTR) with expansion thoracoplasty may control spinal deformity, allow spinal growth, and address thoracic insufficiency syndrome in children with nonsyndromic complex congenital spinal deformities. Methods: Eight pediatric spine centers prospectively entered clinical and radiographic data into a database on every congenital spinal deformity treated with VEPTR as part of an Food and Drug Administration study. We retrospectively reviewed these data and excluded patients with spina bifida, Jarcho-Levin, or other syndromes. Data analysis focused on surgical technique and expansion frequency, change in Cobb angle and thoracic heights, and adverse events for a consecutive series of patients with at least 2 years of follow-up. Results: Twenty-four children with an average age at surgery of 3.3 years (range, 1.0 to 12.5 y) were treated with VEPTR insertion and expansion thoracostomy and were followed for an average of 40.7 months (range, 25 to 78 mo). Twenty-three (95.8%) had associated rib fusions. All patients had subsequent expansion surgery; 50% had 5 or more expansions. Twenty patients (83.3%) had an improvement in Cobb angle during treatment with an average improvement of 8.9 degrees. All had an increase in thoracic height, with a mean increase of 3.41 cm. The most common adverse events were device migration in 7 patients and infection or skin problems in 6 patients. Conclusions: VEPTR insertion with expansion thoracoplasty represents a successful treatment paradigm for nonsyndromic congenital spinal deformities. We report multicenter data with midterm follow-up of children without syndromic diagnoses, in which the vast majority had an improvement in Cobb angle and thoracic height over the treatment period. Challenges include the demands of multiple procedures, skin problems, and device migration. Level of Evidence: Level IV—prognostic study.

The effect of increased distraction frequency on soft tissues during limb lengthening in an animal model

The purpose of this study was to compare the effect of distraction frequency on soft tissues. Ten rabbits underwent high-frequency, automated distraction at 1,440 increments per day, whereas five rabbits were manually distracted at a low frequency of three increments per day. The tibias were lengthened approximately 20% at a rate of 1.05 mm/day. The results indicate that all animals had decreased range of motion of the ankle; however, the high-frequency group fared better compared with the low-frequency group (p<0.01). In addition, the P1 latency of the somatosensory evoked potentials did not change in the high-frequency group, but was statistically higher for the low-frequency group (p<0.05). There was no significant difference found in the histologic studies of muscle of either group. Thus increasing the distraction frequency resulted in better range of motion of the ankle joint and maintained normal somatosensory evoked potentials.

Viability and metabolism of cartilage transplanted to physeal regions

Longitudinal bone growth is the ultimate characteristic clinically desired from the physis. Measuring relatively short-term parameters in comparison with growth may help facilitate investigation of physeal reconstruction. We monitored the viability and metabolism of cartilage transplanted to physeal regions in rabbits. In addition to measuring growth, we performed histochemistry and autoradiographic studies. The results indicated that cartilage transplanted in an avascular fashion could remain viable, synthesize proteoglycan, and be associated with growth (although less than normal) relative to controls. Such measurements may be of benefit in pursuing the goal of clinical physeal reconstruction.