Faculty Bibliography

Background/UNASSIGNED:Amniotic Band Syndrome is a clinical constellation of congenital anomalies characterized by constricting rings, tissue synechiae and amputation of body parts distal to the constriction bands. Involvement of the hand with loss of multiple digits not only leads to devastating deformities but also loss of functionality. Methods/UNASSIGNED:In this series, utilizing microvascular transfer of the second toe from both feet, along with local tissue reconfiguration, a tetra-digital hand with simile of normal cascade was reconstructed. A consecutive series of eight children with Amniotic Band Syndrome, younger than two years in age operated on by single surgeon over a twenty five year interval was reviewed. Results/UNASSIGNED:There was no flap loss. The hands were sensate with effective simple prehensile function. Conclusion/UNASSIGNED:Application of Microvascular toe-to-hand transfer for well selected, albeit severe hand deformity in Amniotic Band Syndrome is a valid surgical concept.

Traditional operative management of unstable, pediatric both-bone forearm fractures is fixation of both ulna and radius. Literature suggests single-bone fixation with intramedullary nailing obtains good results and is less technically demanding and invasive. This systematic review evaluates the efficacy of single-bone intramedullary nailing of pediatric both-bone forearm fractures. Medline and Embase were searched for English-language primary studies published in peer-reviewed journals. Two independent investigators extracted data. Eleven papers met the criteria for inclusion. Overall, studies found pronation and supination and radiographic angulation outcomes were comparable in single and both-bone fixation cohorts. Rates of pronation and supination loss and re-angulation were similar for radius-only compared to ulna-only fixation.

Background and Objective(s): Commercially available activity tracking devices present the opportunity to quantify functional changes in ambulatory status of patients with cerebral palsy (CP). The purpose of this study was to assess the accuracy of a waist-based and a wrist-based wearable device for tracking steps and walking distance of children with CP in a controlled setting. Study Design: Prospective cohort study. Study Participants & Setting: Participants were 27 children, mean age of 9.6 years (range, 4-15), with CP and a Gross Motor Function Classification System (GMFCS) score between I and III. Thirteen children were diagnosed with hemiplegia (48%), 13 with diplegia (48%), and 1 with quadriplegia (4%). Seventeen were classified as GMFCS I (63%), 3 as II (11%), and 7 as III (26%). Fourteen children wore ankle-foot orthoses (52%), one wore HKAFO (4%) and 12 wore no orthotics (44%). Four patients used Lofstrand crutches (15%), two used posterior rollators (7%), and 21 patients used no assistive devices (78%). Materials/Methods: Each participant was outfitted with both a waist-based activity tracker, FitBitTM One, and a wrist-based tracker, FitBitTM Flex. They ambulated at a self-selected speed for 670 feet in a hallway. Orthotics and assistive devices were utilized as per the child's normal routine. Number of steps and distance were collected from both trackers. A researcher simultaneously used a tally counter to manually count total number of steps. Pearson correlation coefficients were determined for number of steps from each tracker and the manual count. Mean absolute percent error (MAPE) was calculated for steps for each tracker and the manual count, and for the distance from each tracker and the hallway distance. Results: For number of steps, a strong positive correlation was found between the waist tracker and the manual count (r=0.997), whereas a weak positive correlation was found between wrist tracker and manual count (r=0.223). MAPE for steps was 1% for the waist tracker and 12% for the wrist tracker. For distance, MAPE was 56% for the waist tracker and 41% for the wrist tracker. Conclusions/Significance: The waist-based activity tracker provided an accurate step count. Neither waist-based nor wristbased tracker was accurate for distance measurement. Thus, the walking ability of ambulatory children with CP can be accurately quantified with a readily available inexpensive activity tracker. This has the potential to enable clinicians to assess the effects of various treatments on the real-world activity level of patients with CP

OBJECTIVES: While studies of patients undergoing the Ponseti method for idiopathic clubfoot demonstrate excellent correction after initial treatment, recurrence can occur in more than half of the cases. Few studies have demonstrated the age at which recurrence typically occurs or if age at discontinuation of the foot ankle orthosis (FAO) is associated with risk for surgical intervention. METHODS: Patients with idiopathic clubfoot treated with the Ponseti method with greater than 3 years of follow-up were evaluated. Age at presentation, need for percutaneous Achilles tenotomy, age of initiation of foot abduction orthosis, adherence with FAO, and need for additional treatment were recorded. Severity scores were recorded at initial presentation and yearly throughout follow-up. RESULTS: 110 patients were followed for an average of 5.9 years, and 32 patients required surgical intervention. Patients who eventually required surgery had significantly higher severity scores at presentation. Though they maintained higher scores throughout the follow-up period, they did not demonstrate significantly higher scores until 3 years of age. FAO was used until an average age of 2.6 years (range: 0.4 to 5.1 years). There was a significant difference in the age at which the FAO was stopped in those patients who eventually required surgery versus those who did not (2.2 years versus 2.8 years). CONCLUSIONS: Patients with recurrence after initially successful Ponseti treatment generally do not become distinguishable by our current classification systems until 3 years of age. Patients who used the FAO for more than 2 years were 2.77 times less likely to require surgery than those who used it less than 2 years. FAO use should be continued until at least 3 years of age in patients undergoing Ponseti treatment for idiopathic clubfoot.

Purpose: Abnormal vasculature has been observed in as much as 85% of children with clubfoot. The purpose of this study was to compare foot perfusion between clubfeet and unaffected feet. Methods: A Masimo Radical 7 Pulse Oximeter (Masimo Corporation, Irvine, CA) was used to measure the foot perfusion index (PI) of children five years of age and younger. Patients with clubfoot undergoing nonoperative treatment, and control patients undergoing treatment for orthopedic concerns not involving the foot, were tested. Exclusion criteria for patients with clubfoot were previous clubfoot surgery and non-idiopathic etiology. The PI of the affected clubfeet was compared to the PI of the unaffected feet of the controls. Results: Sixty-six patients were enrolled, 34 with clubfoot (16 bilateral and 18 unilateral), and 32 controls. No significant difference in PI was found between the affected feet and the unaffected feet (3.1 vs. 2.5; P = 0.200). Conclusion: This analysis showed no difference in PI between clubfeet and unaffected feet of controls. Significance: Although abnormal vasculature in clubfoot has been reported, the perfusion to a non-operative treated clubfoot is similar to an unaffected foot

INTRODUCTION: Growth modulation has been recognized as early as 1905 in the orthopaedic literature. It uses growth potential to correct deformities with an easy procedure; thus avoiding osteotomies and their associated risks if the problem is to be addressed later in adulthood. The tension band plate (TBP) has replaced the Blount staple for growth modulation due to its ease of application and better complication profile, namely implant breakage and extrusion. However, the unpredictable time to effect of the TBP is still an issue. We are not aware of any study that has looked into the use of a locking plate compared to a non-locked plate in growth modulation. We hypothesize that the locking plate will be superior to the nonlocking plate in predicting the time to effect in growth modulation. METHODS: A Sawbones model was created to simulate pediatric metaphyseal bone. One-millimeter thick medium-low density closed-cell urethane foam was fixed to medium density, open-cell urethane foam using Gorilla glue (Figure 1b). Blocks were then made measuring 3x2x2.5 cm in dimensions. A two-hole foot plate (THLP) that allowed for locking and non-locking configurations was selected to test the hypothesis. The test specimen consisted of two blocks held together using the implant being studied (Figure 1a). Metal clips were applied on the contralateral side of the block for loading purposes. There were four test groups in this study. Groups 1 and 2 had the conventional TBP with parallel and divergent screw configurations, respectively. Groups 3 and 4 had the THLP in non-locked and locked configurations, respectively. The four groups were tested using a pulley loading apparatus (Figure 1c) with weight increments of 500 grams to a maximum of 2500 grams. Distraction across the blocks was measured using a caliper. The data obtained was then analyzed using the Kruskall-Wallis one-way analysis of variance on Stata to look for differences in distraction among the groups. RESULTS: There was a significant difference between the groups at loads of 1500 grams and higher (Figure 2). A Post Hoc Dunn's test was then performed to look into the source of difference. There was a significant difference showing a superiority of the THLP in the locking configuration over the conventional TBP in both parallel and divergent screw configurations. There was also a significant superiority, though to a lesser extent, of the THLP in the locking over the non-locking configuration (Figure 3). DISCUSSION: The aim of guided growth is to achieve a point fixation on one side of the physis that will result in a pressure gradient, leading to an incremental increase in growth away from that point fixation. Traditionally the Blount staple achieved this desired effect. The complications of the staple, namely extrusion and breakage, made this implant less appealing. The TBP replaced the Blount staple for its ease of application and better complication profile. Biomechanical studies looked into the best screw configuration to achieve the desired effect and parallel screws were reported to be superior to others. However, the time to effect is still an issue, which may be critical in children with little growth potential remaining. By locking the plate, we achieved a point fixation superior to the non-locked plate and conventional TBP. This is a Sawbone study. Further studies on animal models are needed to confirm these findings and to elucidate whether the locked plate maintains the same safety profile as the TBP

INTRODUCTION: Legg-Calve-Perthes disease is a pediatric condition that occurs when blood supply is temporarily interrupted to the femoral head of the hip joint. Most animal models in the literature induce necrosis by surgical techniques, but our aim was to test whether non- surgical methods could be utilized, particularly as that would be a closer match to the true pathophysiology of LCPD. Avascular necrosis has been observed in the epiphyseal nuclei of the femoral head in 33 per cent of Wistar-Kyoto rats housed in high feeding cages, due to the repetitive mechanical stress on the femoral heads at 5 to 9 weeks (1). This is comparable to the rate of induction of the radiological and histological characteristics of LCPD in New Zealand rabbits using microtrauma with a vibratory motor (2). METHODS: We induced osteonecrosis in Wistar Kyoto rats (WKYs) as described by Masatsugu Suehiro et al (1). In the treatment group, six 5 week old male Wistar Kyoto rats (WKYs) from Charles River Labs were housed in high cages for 10 weeks. The high cages were High temperature Polysulfone Type 2000 static rat cages (Allentown) in which the feed-box and the drinking aperture were placed at a height (27 cm height), such that the rats were forced to stand erect on the hind limbs while drinking and feeding. In the control group, two similarly aged male WKYs were housed in regular low cages (height 10 cm) for the same time period, and allowed to drink and feed without standing. Subsequently, the femoral heads were assessed in both groups by radiological and pathological methods. RESULTS: Radiological evaluation was used to make specific femoral head measurements and calculations for medial neck length (MNL), lateral neck length (LNL), width of femoral head (WH), and curvature radius (CR), as mentioned in Suehiro et al (3). Table 1 shows the radiological measurements for LNL, MNL, WH and CR in the control and osteonecrosis groups. The t-test was done to measure the significance of the differences between the mean of both groups. In the osteonecrosis group, the shape of the femoral head had a flatter appearance with an increased CR and decreased WH (Fig. 1). Histopathological evaluation, using Hematoxylin and Eosin (H&E) stain, revealed a diffuse presence of empty lacunae accompanied by bone marrow cell necrosis in the bone trabeculae of the osteonecrosis group. (Fig.2) DISSCUSSION: Histopathological evaluation revealed cartilage thinning in the femoral head along with discontinuity and clusters of chondrocytes of the osteonecrosis (standing) group. Also, there was necrosis of osteocytes in the bone marrow and bone trabeculae. Empty lacunae were also observed in sections of the reparative bone. These pathological changes indicated osteonecrosis similar to those of early-stage Perthes' disease in the standing group. Our findings agree with current literature that overload or excessive mechanical stress on the femoral head seems to contribute to the etiology of osteonecrosis in WKYs. (Table Presented)

Since the introduction of vaccines, the impact of vaccinations has been immeasurable. Under the current immunization guidelines, infants receive the first of their routine infant vaccinations at 2 months of age. While the benefits of routine infant vaccinations in premature infants have been demonstrated, there is relatively little data on the dosing of these vaccines in premature infants. The medical records of two premature infants who developed intramuscular abscesses after receiving their routine infant vaccinations were reviewed. Both patients developed pain in the area of the injection after receiving their vaccinations. Magnetic resonance imaging findings confirmed the formation of an abscess. No other causes of abscess formation were observed. Both patients required surgical intervention and were treated with a course of antibiotics. To our knowledge, this is the first case report to suggest routine vaccinations as a potential cause of abscess formation in premature infants.

Gradual distal fibula lengthening (DFL), in conjunction with other procedures, was used to correct ankle valgus and short fibulae in three pediatric patients with multiple hereditary exostoses (MHE). The average amount of DFL was 15 mm with a mean follow-up of 2.9 years. Final radiographs showed that all three patients had a stable ankle mortise without evidence of talar tilt or widening. In conclusion, gradual DFL has the advantage of restoring anatomy in cases of ankle valgus due to short fibulae and MHE, and may be performed in conjunction with other procedures.