Sex related difference in postoperative pain and opioid use following posterior spinal fusion for adolescent idiopathic scoliosis.

PURPOSE: This project aims to evaluate the relationship between biological sex and postoperative pain and in patients receiving posterior spinal fusion for adolescent idiopathic scoliosis. METHODS: This is a retrospective study of patients (n=137) aged 10-17 receiving posterior spinal fusion for adolescent idiopathic scoliosis between 01/2018 and 09/2022. Each patient received surgery by the same pediatric orthopedic surgeon with identical postoperative pain management regimen at a children's hospital or a tertiary referral center with a pediatric spine program. RESULTS: There were no significant differences in any background characteristics between the male and female patients, including age, BMI, number of levels fused, preoperative degree of scoliosis, and length of surgery and anesthesia (p>0.05). There were no differences in amount given of any intraoperative medications, nor in amount of postoperative scheduled analgesics (p>0.05). Female patients demonstrated higher average pain scores on Visual Analogue Scale evaluations during the first 24 hours postoperatively (5.0 vs 3.6, p<0.0001), 24-48 hours postoperatively (4.9 vs 4.0, p=0.03), and at the first physical therapy evaluation (5.3 vs 3.8, p<0.001). These patients received significantly greater amounts of morphine milligram equivalents in the first 24 hours postoperatively (42.2 vs 31.5, p=0.01) and for the hospitalization in total (63.8 vs 51.3, p=0.048). There was no difference in hours until hospital discharge (44.3 vs 42.6, p=0.62) nor until first ambulation (20.1 vs 21.3, p=0.24) between the female and male patients. CONCLUSION: The influence of biopsychosocial factors on postoperative pain in adolescents is complex. This study adds to the existing pool of literature suggesting differences in pain perception between adolescent female and male patients. Female patients undergoing posterior spinal fusion for adolescent idiopathic scoliosis may benefit from increased preoperative counseling and more aggressive intra- and postoperative pain management regimens.

Evidence for a Multimodal Pain Management Regimen in Reduction of Postoperative Opioid Use in Pediatric Patients Receiving Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: This project aims to evaluate the relationship between increased use of intraoperative nonopioid analgesics, muscle relaxers, and anesthetics and postoperative outcomes, including opioid utilization, time until ambulation, and hospital length of stay. SUMMARY OF BACKGROUND DATA: Adolescent idiopathic scoliosis (AIS) is a structural deformity of the spine that occurs in otherwise healthy adolescents, occurring with a frequency of 1% to 3%. Up to 60% of patients receiving spinal surgeries, particularly posterior spinal fusion (PSF), experience at least 1 day of moderate-to-severe pain after surgery. PATIENTS AND METHODS: This is a retrospective chart review of pediatric patients aged 10 to 17 having received PSF with >5 levels fused for AIS at a dedicated children's hospital and a regional tertiary referral center with a dedicated pediatric spine program between January 2018 and September 2022. A linear regression model was used to evaluate the influence of baseline characteristics and intraoperative medications on the total amount of postoperative morphine milligram equivalents received. RESULTS: There were no significant differences in the background characteristics of the two patient populations. Patients receiving PSF at the tertiary referral center received equivalent or greater amounts of all nonopioid pain medications and demonstrated decreased time until ambulation (19.3 vs . 22.3 h), postoperative opioid use (56.1 vs . 70.1 MME), and postoperative hospital length of stay (35.9 vs . 58.3 h). Hospital location was not individually associated with a difference in postoperative opioid use. There was not a significant difference in postoperative pain ratings. When accounting for all other variables, liposomal bupivacaine had the greatest contribution to the decrease in postoperative opioid use. CONCLUSION: Patients receiving greater amounts of nonopioid intraoperative medications utilized 20% fewer postoperative morphine milligram equivalents, were discharged 22.3 hours earlier and had earlier recorded evidence of mobility. Postoperatively, nonopioid analgesics were as effective as opioids in the reduction of subjective pain ratings. This study further demonstrates the efficacy of multimodal pain management regimens in pediatric patients receiving PSF for AIS.

Slipped capital femoral epiphysis and associated hypothyroidism. A review of the literature with two classic case examples.

Slipped capital femoral epiphysis (SCFE) is a relatively common hip disorder often seen in overweight, peripubertal children. Although the exact etiology is uncertain, it is generally accepted that underlying endocrinopathies play a role in the pathogenesis. Hypothyroidism is the endocrine disorder cited most commonly in association with SCFE, and patients often have no history of thyroid dysfunction at the time of presentation. Despite being a well-recognized risk factor, recommendations for screening thyroid function in patients with typical presentations of SCFE have not been deemed cost-effective; however, there is data to support screening for hypothyroidism in patients with atypical presentations of SCFE or short stature. Hypothyroidism may have a significant impact on healing and bone union after surgical management of SCFE and there is a paucity of case reports in the literature describing potential peri- and postoperative complications. We performed a systematic review of the literature of all reported cases of SCFE with associated hypothyroidism using the search terms, which demonstrated a physiologic relationship between hypothyroidism and SCFE. Two case reports of SCFE in patients with hypothyroidism and associated complications are presented with the literature review. There is a physiologic relationship between thyroid dysfunction and SCFE, and we postulate that profound hypothyroidism may contribute to delayed healing or nonunion in patients undergoing operative management. We support the recommendation to screen patients with short stature, atypical presentation of SCFE, or perisistent nonunion after surgery. In cases of hypothyroidism, we recommend thyroid hormone replacement and laboratory confirmation of return to euthyroid state prior to operative intervention.

Childhood Obesity Increases the Risk of Failure in the Treatment of Distal Forearm Fractures.

BACKGROUND: Childhood obesity is a national problem that has gained significant attention in both the medical literature and the national media. Obesity in the adult population has been associated with increased failure of conservative treatments. Our hypothesis is that childhood obesity is associated with a loss of reduction after closed treatment of distal radius fractures. METHODS: A total of 157 patients with consecutive distal radius fractures who underwent closed reduction in the emergency department or the operating room were included from the office records of the sole pediatric orthopaedic subspecialist group in a metropolitan area from January 2011 to June 2012. All cases were initially treated with fiberglass casting with or without closed reduction. All patients completed the casting treatment and demonstrated radiographic union. Patients' age, weight, height, number of office visits, subsequent surgeries, and fracture angulation were recorded and analyzed. RESULTS: Sixty-six (42%) children were overweight (BMI>85th percentile) and 46 (29%) children met the criteria for obesity (BMI>95th percentile). Fourteen normal-sized children (12%) and 13 obese children (28%) required a reduction in the operating room after initial treatment, which was significant (P=0.02). Obese children needed significantly more visits requiring radiographs (P=0.004). Obese children were significantly less likely to have an initial perfect reduction in the emergency room (P=0.005). CONCLUSIONS: The results of closed reduction and casting for displaced distal radius fractures are typically excellent with few complications or risks. The present study supports the hypothesis that obesity results in a higher rate of malreduction and subsequent manipulations with closed reduction and casting. Close follow-up and early consideration for additional treatment in this patient population may help reduce the need for further manipulations. LEVEL OF EVIDENCE: Level III.

Sports participation and radiographic findings of adolescents treated nonoperatively for displaced clavicle fractures.

BACKGROUND: There is a relative paucity of high-level evidence that guides the treatment of displaced midshaft clavicle fractures in adolescents. Some use overhead sports or significant shortening as relative indications for surgical treatment, while others rarely consider operative intervention for these patients. The purpose of this study is to determine the effect of overhead sports participation and fracture shortening on subjective and objective outcomes after nonoperative treatment of displaced midshaft clavicle fractures in those aged 10-17 years. METHODS: Using a radiographic database, adolescents with displaced clavicle fractures were identified and contacted over the phone. These subjects were invited to take part in the study in return for compensation. Radiographic measurements of dedicated clavicle films around the time of injury were performed, and a custom survey aimed at elucidating participation in overhead or contact sports was given. The Nottingham Clavicle Score (NCS) and the Constant Shoulder Score were obtained for each patient to provide both subjective and objective outcome data. Statistical Package for Social Science (SPSS) software (version 22, IBM) was used to compare radiographic and sports data to the outcome measures. RESULTS: Gender, age at the time of fracture, time since fracture, relative and absolute radiographic shortening, and hand dominance were all not significantly correlated with subjective or objective outcomes. Five patients (23%) reported not feeling happy with the appearance of their shoulder at the beach or at the pool. This group had statistically lower NCS results. Eleven of 22 participated in ≥6 months per year of overhead or contact sports; they did not have worse subjective or objective outcomes. CONCLUSIONS: Fracture shortening and sports participation do not have a significant impact in adolescents on outcomes after displaced midshaft clavicle fracture.

Assessment and treatment of children with cerebral palsy.

Children with cerebral palsy are prone to development of musculoskeletal deformities. The underlying neurlogic insult may results in a loss of selective motor control, an increase in underlying muscle tone, and muscle imbalance, which can lead to abnormal deforming forces acting on the immature skeleton. The severely involved child is one who is at increased risk for developing progressive musculoskeletal deformities. Close surveillance and evaluation are key to addressing the underlying deformity and improving and maintaining overall function.

Dural ectasia in a child with Larsen syndrome.

INTRODUCTION: We present a case of an incidental finding of dural ectasia in a child diagnosed with Larsen syndrome. Larsen syndrome is a rare inherited disorder of connective tissue characterized by facial dysmorphism, congenital joint dislocations of the hips, knees and elbows, and deformities of the hands and feet. Dural ectasia is as an abnormal expansion of the dural sac surrounding the spinal cord and may result in spinal morphologic changes, instability, and spontaneous dislocation. To the best of our knowledge, the presence of dural ectasia in Larsen syndrome has not previously been reported. CASE STUDY: A 6-year-old boy diagnosed with Larsen syndrome presented with an upper thoracic curve measuring 74 degrees, a right thoracic curve measuring 65 degrees, and significant cervicothoracic kyphosis with 50% anterior subluxation of C6 on C7 and C7 on T1. Advanced imaging studies showed dural ectasia (evidenced by spinal canal and dural sac expansion), thinning of pedicles and lamina, and C4 and C6 pars defects with cervical foramen enlargement. The patient received growing rod instrumentation (attached to cervical spine fixation) by a combined anterior/posterior surgical approach using intraoperative halo. Complications included intraoperative medial breach (fully resolved), wound dehiscence, 2 instances of bilateral broken rods, and a broken cervical rod. Following 7 lengthening procedures, the patient underwent definitive fusion. DISCUSSION: Surgeons should be aware of the potential for dural ectasia in patients with Larsen syndrome. Its presence will cause difficulties in the surgical intervention for spinal deformity. Multiple factors must be considered, and surgical approach and technique will require modification to avoid complications. Although dural ectasia confounds surgical intervention in these patients, surgery still appears to outweigh the risks associated with delayed intervention. The presence of dural ectasia should not preclude surgical decompression and stabilization. This report adds to the body of knowledge on the treatment of Larsen syndrome by demonstrating the potential existence of dural ectasia and highlights the importance of careful and thorough preoperative evaluation and diagnostic imaging.

The effect of tranexamic acid in blood loss and transfusion volume in adolescent idiopathic scoliosis surgery: a single-surgeon experience.

PURPOSE: Intraoperative blood loss in scoliosis surgery often requires transfusions. Autogenous blood decreases but does not eliminate risks typically associated with allogenic blood transfusion. Costs associated with transfusions are significant. Tranexamic acid (TXA) has been shown to decrease blood loss in cardiac and joint surgery. Few studies have examined its use in pediatric spine surgery, and the results are inconsistent. The aim of this study was to determine whether TXA decreases intraoperative blood loss and transfusion requirements in adolescent idiopathic scoliosis patients undergoing posterior spinal fusion by a single surgeon. METHODS: The medical records and operative reports of surgically treated patients with adolescent idiopathic scoliosis between 2000 and 2009 were retrospectively reviewed. The inclusion criteria were: (1) patients who underwent instrumented posterior spinal fusion, (2) had complete medical records, and (3) were treated by the same surgeon. Forty-nine patients who met the inclusion criteria were divided into two groups: Group A (25 patients) received TXA, while Group B (24 patients) did not receive TXA. RESULTS: After controlling for age at the time of surgery, gender, and number of vertebral levels fused, the mean intraoperative blood loss was significantly lower in Group A (537 ml) than in Group B (1,245 ml) (p = 0.027). The mean volume of blood transfused intraoperatively was 426 and 740 ml for Group A and Group B, respectively. The difference was not statistically significant after controlling for age, gender, and number of levels fused (p = 0.078). CONCLUSION: TXA significantly decreased intraoperative blood loss in posterior spinal fusions performed for adolescent idiopathic scoliosis.

MRI findings in adolescent patients with acute traumatic knee hemarthrosis.

BACKGROUND: Physical examination may be inconclusive in adolescents presenting with an acute traumatic knee effusion because of pain and guarding. The purpose of this study was to describe the magnetic resonance imaging (MRI) findings in adolescents with traumatic knee effusions and to compare injuries based on age, sex, and physeal maturity. METHODS: All MRIs using a knee trauma protocol performed at our institution over a 2-year period were evaluated. One hundred thirty-one patients between the ages of 10 to 18 years of age with a clinical history of acute knee trauma and an effusion confirmed on MRI met our study inclusion criteria. They were divided into 2 age groups: 10 to 14 and 15 to 18 years old. Pathology was confirmed using clinical history, MRI, and any available surgical reports. RESULTS: Of the 131 patients with an acute knee effusion, there were 59 patients in the younger group (10 to 14 y old) and 72 patients in the older group (15 to 18 y old). In the younger group, patellar dislocations (36%), anterior cruciate ligament (ACL) tears (22%), and isolated meniscus tears (15%) were the most common injuries. In the older group, ACL tears (40%), patellar dislocations (28%), and isolated meniscus tears (13%) were the most common injuries. ACL injuries represented 28% of injuries in males and 38% of injuries in females, whereas patellar dislocations represented 28% of injuries in males and 37% of injuries in females. There was a trend toward adolescents with active growth plates sustaining more patellar dislocations and adolescents with closed growth plates sustaining more ACL injuries. Forty-one percent of patients in this study underwent surgery. CONCLUSIONS: Patellar dislocation is a common injury in children who present with a traumatic knee effusion, especially in young adolescents and females. Adolescents presenting with a traumatic knee effusion should undergo MRI because of the high rate of positive findings missed by physical examination and plain radiographs that may warrant surgical repair or reconstruction. LEVEL OF EVIDENCE: Level III.

The findings of preoperative cardiac screening studies in adolescent idiopathic scoliosis.

INTRODUCTION: We sought to evaluate findings of screening cardiac studies in adolescent idiopathic scoliosis (AIS) patients by reviewing the echocardiograms and electrocardiograms (EKGs) performed at their preoperative evaluation for spinal fusion. METHODS: Retrospective chart review of all surgical AIS patients from 2000 to 2007 was completed (n=212). Patients with neuromuscular scoliosis, known connective tissue disease, or known/suspected cardiac disease were excluded. In presurgical screening, 12 lead EKG, 2dimensional-Doppler, and M-mode echocardiograms were analyzed. RESULTS: A total of 154 (73%) female and 58 (27%) male patients (aged 12 to 18 y, avg: 14.8 y) were analyzed. EKG findings, 180/212 (85%), were within normal limits. Twenty-eight of 212 (13%) patients were found to have normal variant readings. Four of 212 (2%) patients met criteria for left ventricular hypertrophy on EKG, but were subsequently found to have normal echocardiograms. Significant echocardiogram findings revealed 2 (0.94%) subjects with atrial septal defects (ASDs) (that delayed surgery) and 7 (3.3%) subjects with aortic root/valve abnormalities. CONCLUSIONS: In our cohort of preoperative AIS patients, cardiac abnormalities ranged from mild to severe, and in 2 cases, affected the surgical timing. Novel findings of aortic abnormalities were identified in 3.3% of patients. In a study which examined the prevalence of heart disease in randomly selected healthy adolescents with previously unknown cardiac disease (Steinberger), there was a rate of 3.6% (13/357) of cardiac anomalies. Of note, only 0.6% had aortic root/valve findings. The results of our retrospective review indicate that EKG does not provide significant information compared with echocardiogram as part of the preoperative evaluation of asymptomatic and otherwise healthy patients with AIS who are undergoing spinal deformity surgery. However, use of the echocardiogram may be appropriate for the diagnosis of previously unknown cardiac abnormalities in this population, as aortic root/valve abnormalities seem to be unique findings in these patients. LEVEL OF EVIDENCE: Level IV, Retrospective, descriptive case series.

Effects of Hydrostatic Loading on a Self-Aggregating, Suspension Culture-Derived Cartilage Tissue Analog.

OBJECTIVE: Many approaches are being taken to generate cartilage replacement materials. The goal of this study was to use a self-aggregating suspension culture model of chondrocytes with mechanical preconditioning. DESIGN: Our model differs from others in that it is based on a scaffold-less, self-aggregating culture model that produces a cartilage tissue analog that has been shown to share many similarities with the natural cartilage phenotype. Owing to the known loaded environment under which chondrocytes function in vivo, we hypothesized that applying force to the suspension culture-derived chondrocyte biomass would improve its cartilage-like characteristics and provide a new model for engineering cartilage tissue analogs. RESULTS: In this study, we used a specialized hydrostatic pressure bioreactor system to apply mechanical forces during the growth phase to improve biochemical and biophysical properties of the biomaterial formed. We demonstrated that using this high-density suspension culture, a biomaterial more consistent with the hyaline cartilage phenotype was produced without any foreign material added. Unpassaged chondrocytes responded to a physiologically relevant hydrostatic load by significantly increasing gene expression of critical cartilage molecule collagen and aggrecan along with other cartilage relevant genes, CD44, perlecan, decorin, COMP, and iNOS. CONCLUSIONS: This study describes a self-aggregating bioreactor model without foreign material or scaffold in which chondrocytes form a cartilage tissue analog with many features similar to native cartilage. This study represents a promising scaffold-less, methodological advancement in cartilage tissue engineering with potential translational applications to cartilage repair.

Case report: primary aneurysmal bone cyst of the epiphysis.

Aneurysmal bone cysts are benign active or aggressive bone tumors that commonly arise in the long bones, especially the femur, tibia, and humerus and the posterior elements of the spine. Aneurysmal bone cysts affect all age groups but are more common before skeletal maturity (first two decades of life). They usually involve the metaphysis or metadiaphyseal region of long bones. Although juxtaphyseal lesions abutting the growth plate and extending into the epiphysis have been described, there is no report of an aneurysmal bone cyst entirely and primarily located in the epiphysis. We report on a 3-year-old boy who presented with an entirely contained aneurysmal bone cyst to the proximal tibial epiphysis. We discuss the clinical presentation, diagnosis, including imaging and pathology, and treatment. A review of the pertinent literature also is presented.

Factors related to progression of thoracolumbar kyphosis in children with achondroplasia: a retrospective cohort study of forty-eight children treated in a comprehensive orthopaedic center.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To assess the period prevalence and predisposing factors in thoracolumbar kyphosis progression (TLK). SUMMARY OF BACKGROUND DATA: TLK is a common presentation in children with achondroplasia. This condition occurs very early in life; it is observed during the first attempts to sit, and has multifactorial etiology. Studies are limited on the radiologic assessment of the angle of wedging of the deformed vertebra, but none to our knowledge on TLK progression in achondroplasia. METHODS: The records of 48 of 103 children with achondroplasia seen between 1997 and 2005 were examined. Developmental motor delay (DMD) and other potential predictors of TLK were assessed. The criteria for DMD were a child's inability to sit without support by 6 months and an inability to walk independently by 15 months. Lateral radiographs were examined for the magnitude of TLK, thoracic kyphosis, lumbar lordosis, percentage of apical vertebral wedging for the height and width of the vertebra, and apical vertebral translation. The association between TLK progression and potential predisposing factors were assessed using chi test, Fisher exact, t test, and binomial regression model for predictor identification. RESULTS: The period prevalence of TLK progression in children with achondroplasia was 35.4%. TLK progression was significantly related to DMD, risk ratio = 2.40, 95% confidence interval = 1.10 to 5.58, apical vertebral translation (P = 0.01), and percentage apical vertebral wedging for height (P = 0.01). After adjustment for relevant covariates, the relationship between DMD and TLK progression persisted, risk ratio = 2.65, 95% confidence interval, 1.20 to 5.91. CONCLUSION: DMD was significantly associated with TLK progression and other radiologic parameters namely, initial TLK of >25 degrees , percentage of apical vertebral wedging for the height of the vertebra, and apical vertebral translation.

Update on congenital spinal deformities: preoperative evaluation.

STUDY DESIGN: Review. OBJECTIVE: To review and outline the preoperative evaluation and approach in assessing children with congenital vertebral malformation. SUMMARY OF BACKGROUND DATA: Congenital vertebral malformations encompass a broad spectrum of conditions. A high association of renal, cardiac, and intraspinal anomalies with congenital vertebral malformation has been well documented in the literature. Vertebral malformation with involvement of the thoracic cage may lead to the development of thoracic insufficiency. The natural history, the character, and location of the deformity ultimately influence the propensity for progression and the necessity for treatment. Multiple factors should be considered before treatment with the goal of treatment aimed at providing the best possible care to be able to optimize the child's overall function and potential for growth. METHODS: Narrative and review of literature. CONCLUSION: Congenital scoliosis is a multifaceted condition. The presentation of the condition can be quite varied from those presenting with an isolated hemivertebrae to those with severe malformations, complicated by multiple medical conditions. A thorough preoperative evaluation is necessary before the institution of any treatment protocol. The presence of any medical condition must be addressed; the treatment should be tailor-made for each patient putting into consideration the patients' age and the effects of treatment on pulmonary function at maturity.

Organophosphorus pesticide ozonation and formation of oxon intermediates.

In the present study, organophosphorus pesticides (OPs) (diazinon, methyl parathion, and parathion) were oxidized by bubbling ozone into a glass reactor. OP residues were detected using HPLC and ozonation intermediates were identified using GC-MS. The degradation of OPs followed pseudo-first-order kinetics through direct ozone oxidation and indirect hydroxyl radical oxidation. Diazinon, based on its relatively higher degradation constant, was easily degraded by ozonation. Increasing the pH of the solution accelerated diazinon degradation, but little effect was observed for methyl parathion or parathion. Diazoxon, methyl paraoxon and paraoxon were identified as ozonation intermediates of diazinon, methyl parathion and parathion, respectively. The ozonation of the PS group results in the formation of oxon intermediates, which suggests that OPs with this group would be degraded in a similar manner to that seen for the OPs tested in this study. Diazoxon was completely decomposed by ozonation in 30min, while trace methyl paraoxon and paraoxon accumulated to different amounts when the solution pH was varied. The presence of oxon intermediates should be noted in OP removal by ozonation.

Musculoskeletal effects of obesity.

PURPOSE OF REVIEW: The problem of obesity has become a global concern, with increased prevalence reported in the literature. Numerous comorbid conditions are known to be associated with obesity; its relationship with the development and function of the musculoskeletal system in the growing child is poorly understood. This article reviews the current literature on the various musculoskeletal effects associated with obesity in children and adolescents. RECENT FINDINGS: The association between obesity and various musculoskeletal disorders such as slipped capital femoral epiphysis and Blount disease is well reported. Its effects on the structure and function of the musculoskeletal system have not been well documented. Recent studies suggest an increased association between obesity and musculoskeletal pain and increased fracture risk. The limitations imposed by increasing body mass appear to be directly reflected in the child's level of activity and overall functional capacity. SUMMARY: Obesity continues to pose a serious health concern. Its impact on the development of the child's musculoskeletal system is still poorly understood. Recent data suggests that obesity affects the child's locomotor system both functionally and structurally. As the obesity epidemic grows, newer studies will be needed to help us fully understand the true impact of obesity on the musculoskeletal system of the growing child.

Efficacy and safety of percutaneous epiphysiodesis.

BACKGROUND: The aims of this study were to evaluate outcomes of percutaneous epiphysiodesis, as described by Bowen, in 97 patients and to assess complications and determine whether the effect of the epiphysiodesis will accurately follow the Moseley chart predictions. METHODS: A total of 97 patients were reviewed retrospectively. Fifty-six girls and 41 boys, with a mean skeletal age of 12.6 years (range, 10-16 years) at the time of operation, were followed up until skeletal maturity, a mean of 3.8 years (range, 1-10 years). RESULTS: The mean residual leg length discrepancy (LLD) in 88 patients at maturity was 1.3 cm (range, 0-3.5 cm). In 9 patients, the epiphysiodesis was combined with a femoral lengthening or femoral shortening. The residual leg length discrepancy in these 9 patients was 3.3 cm at maturity (range, 0-6.5 cm). Minor complications including knee effusion (n = 2), superficial wound infection (n = 1), and exostosis (n = 3) occurred in 6 patients. Failure of the epiphysiodesis was the only major complication seen (n = 3). CONCLUSIONS: This study shows that complications are infrequent when performing percutaneous epiphysiodesis and that the Moseley straight-line method accurately and efficaciously predicted the timing for percutaneous epiphysiodesis in all but one patient who had unpredictable growth from hemihypertrophy secondary to a hemangiomatosis.

Case reports: pediatric PCL insufficiency from tibial insertion osteochondral avulsions.

Posterior cruciate ligament (PCL) insertion-site osteochondral avulsions in children, particularly from the tibia, are not commonly seen by orthopaedic surgeons. Because of the rarity of these injuries, careful attention to the specific physical examination and imaging findings seen with these injuries is necessary so that the proper diagnosis can be made. Osteochondral avulsions of the PCL can be missed on plain radiographs in skeletally immature patients, and therefore magnetic resonance imaging is necessary for proper diagnosis. With this knowledge, clinicians can formulate treatment plans which can return their patients to activities while avoiding potential morbidity resulting from missed diagnoses or improper treatment. We report two rare cases of PCL insufficiency stemming from tibial insertion osteochondral avulsions. Both patients underwent subsequent open reduction and internal fixation of the avulsion using two different fixation methods (bioabsorbable anchors versus cannulated screw and washer) and have returned to full sporting activities.

The correction of leg-length discrepancy after treatment in developmental dysplasia of the hip by using a percutaneous epiphysiodesis.

The aims of this study were to determine factors that cause a leg-length discrepancy (LLD) to the extent that correction is indicated after treatment in developmental dysplasia of the hip and determine whether the LLD may be treated with a percutaneous epiphysiodesis. Twelve children were included in this study. The factors which caused LLD were avascular necrosis, femoral shortening and varus at reduction, and septic arthritis. Percutaneous epiphysiodesis of the contralateral limb reduced the mean predicted LLD from 3.8 to 1.2 cm at maturity. We concluded that LLD (>2.5 cm) might result from complications of developmental dysplasia of the hip and these patients can be treated with a percutaneous epiphysiodesis.

Effects of organophosphorus pesticides and their ozonation byproducts on gap junctional intercellular communication in rat liver cell line.

The effects of organophosphorus pesticides (OPs), oxons and their ozonation byproducts on gap junctional intercellular communication (GJIC) on cultured BRL cell line were investigated using scrape loading and dye transfer (SL/DT) technique. The neutral red uptake assay was used to identify the non-cytotoxic levels of diazinon, parathion and methyl-parathion applied to GJIC assay. The concentration-dependent inhibition of GJIC was observed over a range of 50-350 mg/l diazinon, parathion and methyl-parathion after 90 min incubation compared with the vehicle control. However, oxons and ozonation byproducts of OPs had no inhibition effect on GJIC at any of the concentrations tested. The inhibition of GJIC by OPs was reversible after removal of the tested pesticides followed by incubation with fresh medium. The present study suggested that the ozonation treatment could be used for the detoxification of drinking water and food crops contaminated with diazinon, parathion and methyl-parathion without formation of GJIC toxicity.