Proximal femoral growth disturbance in developmental dysplasia of the hip: what do we know?

BACKGROUND

Proximal femoral growth disturbance (PFGD) can be the most devastating complication of the treatment of development dysplasia of the hip. The reported incidence ranges from 0% to 73%. The condition involves varying degrees of growth disturbances of the femoral capital epiphysis, the physeal plate or both.

PURPOSE

This manuscript will discuss normal growth and development of the hip, the blood supply to the upper end of the femur, pathological and radiographic changes, classifications used to describe PFGD and, most importantly, the potential causes of these growth disturbances and the authors' strategies for avoiding PFGD.

A novel approach to the study of hypoxia-ischemia-induced clinical and subclinical seizures in the neonatal rat

Perinatal hypoxic-ischemic encephalopathy (HIE) is a major cause of acute mortality and chronic neurologic morbidity in infants and children. HIE is the most common cause of neonatal seizures, and seizure activity in neonates can be clinical, with both EEG and behavioral symptoms, subclinical with only EEG activity, or just behavioral. The accurate detection of these different seizure manifestations and the extent to which they differ in their effects on the neonatal brain continues to be a concern in neonatal medicine. Most experimental studies of the interaction between hypoxia-ischemia (HI) and seizures have utilized a chemical induction of seizures, which may be less clinically relevant. Here, we expanded our model of unilateral cerebral HI in the immature rat to include video EEG and electromyographic recording before, during and after HI in term-equivalent postnatal-day-12 rats. We observed that immature rats display both clinical and subclinical seizures during the period of HI, and that the total number of seizures and time to first seizure correlate with the extent of tissue damage. We also tested the feasibility of developing an automated seizure detection algorithm for the unbiased detection and characterization of the different types of seizure activity observed in this model.

Interhemispheric and intrahemispheric language reorganization in complex partial epilepsy

OBJECTIVE

To investigate interhemispheric and intrahemispheric reorganization in patients with localization-related epilepsy.

METHOD

We studied 50 patients with a left hemispheric focus and 20 normal right-handed controls with a 3T echoplanar imaging blood oxygen level dependent functional MRI auditory-based word definition decision task. Data were analyzed using SPM 2. Using region of interest for Broca and Wernicke areas and an asymmetry index (AI), patients were categorized as left language (LL; AI > or = 0.20) or atypical language (AL; AI <0.20) for region. The point maxima activation for normal controls (p <0.05 corrected FDR) was identified in Broca and midtemporal regions and then used as a point of reference for individual point maxima identified at p < 0.001, uncorrected.

RESULTS

Patient groups showed increased frequency of having activation in right homologues. Activation in AL groups occurred in homologous right regions; distances for point maxima activation in homologous regions were the same as point maxima distances in normal control activation in left regions. Distances for LL patient in left regions showed a trend for differences for midtemporal gyrus (6 mm posterior, 3 mm superior) but variability around mean difference distance was significant. There was no effect of age at epilepsy onset, duration, or pathology on activation maxima.

CONCLUSIONS

Right hemisphere language regions in patients with left hemispheric focus are homologues of left hemisphere Broca and broadly defined Wernicke areas. We found little evidence for intrahemispheric reorganization in patients with left hemisphere epilepsy who remain left language dominant by these methods.

Seizure modulation with applied electric fields in chronically implanted animals

Low Frequency (<<100Hz) applied electric fields have been shown to modulate neuronal activity both In Vitro and in acute whole animal studies. We have been working to apply this technology for seizure control in chronically implanted animals. We have developed electronics for simultaneously recording neural activity while stimulating with low frequency fields. We have observed transient entrainment of spike and wave activity during spontaneous seizures with open loop sinusoidal stimulation with frequencies between 9-15 Hz. This is the first demonstration of low frequency field modulation of neural activity in chronically implanted mammalian brain.

Atypical language in lesional and nonlesional complex partial epilepsy

OBJECTIVE

We investigated the relationship between partial epilepsy, MRI findings, and atypical language representation.

METHODS

A total of 102 patients (4 to 55 years) with left hemisphere epileptogenic zones were evaluated using three fMRI language tasks obtained at 1.5 or 3T with EPI BOLD techniques: verbal fluency, reading comprehension, and auditory comprehension. fMRI maps were visually interpreted at a standard threshold and rated as left or atypical language.

RESULTS

Atypical language dominance occurred in 30 patients (29%) and varied with MRI type (p < 0.01). Atypical language representation occurred in 36% (13/36) with normal MRI, 21% (6/29) with mesial temporal sclerosis, 14% (4/28) with focal cortical lesions (dysplasia, tumor, vascular malformation), and all (6/6) with a history of stroke. Multivariate logistic regression analysis found handedness, seizure onset, and MRI type accounted for much of the variance in language activation patterns (chi(2) = 24.09, p < 0.01). Atypical language was more prevalent in patients with early seizure onset (43.2%, p < 0.05) and atypical handedness (60%, p < 0.01). None of the three clinical factors were correlated with each other (p > 0.40). Patients with atypical language had lower verbal abilities (F = 6.96, p = 0.01) and a trend toward lower nonverbal abilities (F = 3.58, p = 0.06). There were no differences in rates of atypical language across time, age groups, or MRI scanner.

CONCLUSION

Early seizure onset and atypical handedness, as well as the location and nature of pathologic substrate, are important factors in language reorganization.

Seizure focus affects regional language networks assessed by fMRI

OBJECTIVE

To investigate the degree of language dominance in patients with left and right hemisphere seizure foci compared to normal volunteers using a fMRI reading comprehension task.

METHODS

Fifty patients with complex partial epilepsy, aged 8 to 56 years and 33 normal volunteers, aged 7 to 34 had fMRI (1.5 T) and neuropsychological testing. Participants silently named an object described by a sentence compared to a visual control. Data were analyzed with region of interest (ROI) analysis based on t maps for inferior frontal gyrus (IFG), midfrontal gyrus (MFG), and Wernicke area (WA). Regional asymmetry indices (AIs) were calculated [(L - R)/(L + R)]; AI > 0.20 was deemed left dominant and AI < 0.20 as atypical language.

RESULTS

Left hemisphere focus patients had a higher likelihood of atypical language than right hemisphere focus patients (21% vs 0%, chi2 < 0.002). Left hemisphere focus patients, excluding those with atypical language, had lower regional AI in IFG, MFG, and WA than controls. Right hemisphere focus patients were all left language dominant and had a lower AI than controls in WA and MFG, but not for IFG. AI in MFG and WA were similar between left hemisphere focus/left language patients and right hemisphere focus patients. Patients activated more voxels than healthy volunteers. Lower AIs were attributable to greater activation in right homologous regions. Less activation in the right-side WA correlated with better verbal memory performance in right focus/left hemisphere-dominant patients, whereas less strongly lateralized activation in IFG correlated better with Verbal IQ in left focus/left hemisphere-dominant patients.

CONCLUSIONS

Patients had lower asymmetry indices than healthy controls, reflecting increased recruitment of homologous right hemisphere areas for language processing. Greater right hemisphere activation may reflect greater cognitive effort in patient populations, the effect of epilepsy, or its treatment. Regional activation patterns reflect adaptive efforts at recruiting more widespread language processing networks that are differentially affected based on hemisphere of seizure focus.

Acetabular dysplasia after treatment for developmental dysplasia of the hip. Implications for secondary procedures

Untreated acetabular dysplasia following treatment for developmental dysplasia of the hip (DDH) leads to early degenerative joint disease. Clinicians must accurately and reliably recognise dysplasia in order to intervene appropriately with secondary acetabular or femoral procedures. This study sought early predictors of residual dysplasia in order to establish empirically-based indications for treatment. DDH treated by closed or open reduction alone was reviewed. Residual hip dysplasia was defined according to the Severin classification at skeletal maturity. Future hip replacement in a subset of these patients was compared with the Severin classification. Serial measurements of acetabular development and subluxation of the femoral head were collected, as were the age at reduction, type of reduction, and Tonnis grade prior to reduction. These variables were used to predict the Severin classification. The mean age at reduction in 72 hips was 16 months (1 to 46). On the final radiograph, 47 hips (65%) were classified as Severin I/II, and 25 as Severin III/IV (35%). At 40 years after reduction, five of 43 hips (21%) had had a total hip replacement (THR). The Severin grade was predictive for THR. Early measurements of the acetabular index (AI) were predictive for Severin grade. For example, an AI of 35 degrees or more at two years after reduction was associated with an 80% probability of becoming a Severin grade III/IV hip. This study links early acetabular remodelling, residual dysplasia at skeletal maturity and the long-term risk of THR. It presents evidence describing the diagnostic value of early predictors of residual dysplasia, and therefore, of the long-term risk of degenerative change.

Early seizure detection

For patients with medically intractable epilepsy, there have been few effective alternatives to resective surgery, a destructive, irreversible treatment. A strategy receiving increased attention is using interictal spike patterns and continuous EEG measurements from epileptic patients to predict and ultimately control seizure activity via chemical or electrical control systems. This work compares results of seven linear and nonlinear methods (analysis of power spectra, cross-correlation, principal components, phase, wavelets, correlation integral, and mutual prediction) in detecting the earliest dynamical changes preceding 12 intracranially-recorded seizures from 4 patients. A method of counting standard deviations was used to compare across methods, and the earliest departures from thresholds determined from non-seizure EEG were compared to a neurologist's judgement. For these data, the nonlinear methods offered no predictive advantage over the linear methods. All the methods described here were successful in detecting changes leading to a seizure between one and two minutes before the first changes noted by the neurologist, although analysis of phase correlation proved the most robust. The success of phase analysis may be due in part to its complete insensitivity to amplitude, which may provide a significant source of error.

Adaptive electric field control of epileptic seizures

We describe a novel method of adaptively controlling epileptic seizure-like events in hippocampal brain slices using electric fields. Extracellular neuronal activity is continuously recorded during field application through differential extracellular recording techniques, and the applied electric field strength is continuously updated using a computer-controlled proportional feedback algorithm. This approach appears capable of sustained amelioration of seizure events in this preparation when used with negative feedback. Seizures can be induced or enhanced by using fields of opposite polarity through positive feedback. In negative feedback mode, such findings may offer a novel technology for seizure control. In positive feedback mode, adaptively applied electric fields may offer a more physiological means of neural modulation for prosthetic purposes than previously possible.

Sarcomatoid renal cell carcinoma of papillary origin. A case report and cytogenic evaluation

Sarcomatoid renal cell carcinoma (SRCC) is an aggressive tumor variant thought to arise predominantly from dedifferentiation of clear cell carcinoma. A few reports of SRCC associated with non-clear cell tumors led to the presumption that SRCC may arise from any renal cell carcinoma, although direct evidence of this is lacking. Cytogenetic studies on 3 previously documented SRCCs associated with papillary renal cancers showed either 3p deletions or absence of trisomy 7, 17 in the sarcomatoid tumors, suggesting origin from a coexistent clear cell tumor. The present case represents the first conclusive evidence of direct progression of non-clear cell carcinoma to SRCC with both tumor components containing multiple copies of chromosomes 7 and 17. Many genetic anomalies, including p53 mutations, frequently recognized in SRCC were not recognized in this case, highlighting the importance of cytogenetic evaluation of all SRCC. The patient is well and without evidence of tumor progression 1 year after surgery, and the sinister outlook of SRCC in association with clear cell carcinoma may not apply in SRCC of non-clear cell origin.

Acetabular development in developmental dysplasia of the hip complicated by lateral growth disturbance of the capital femoral epiphysis

BACKGROUND

Lateral growth disturbance of the capital femoral epiphysis is the most common type of physeal arrest complicating the treatment of developmental hip dysplasia. Although this type of physeal damage has been assumed to result in poor acetabular development, the natural history of dysplastic hips affected by this pattern of growth disturbance is still unclear. To investigate this issue, we evaluated acetabular development in a retrospective study of fifty-eight hips in forty-eight patients who had lateral physeal arrest after management of developmental hip dysplasia.

METHODS

Of the fifty-eight hips, thirty-six were reduced closed and twenty-two were reduced open. The average age of the patients was twenty-two months (range, three to ninety-seven months) at the time of the reduction and twenty-one years (range, ten to fifty-five years) at the time of the latest follow-up evaluation. Hips rated as Severin class I (an excellent result) or II (a good result) were defined as having a satisfactory result, and those rated as Severin class III (a fair result) or IV (a poor result) were considered to have an unsatisfactory result. Specific femoral head changes were sought in the complete radiographic files on all hips. Various radiographic parameters of hip integrity, including the degree of lateral tilt of the capital femoral epiphysis, were measured over time, and comparisons were made between hips classified as satisfactory and those classified as unsatisfactory at four time-points: before the reduction, at two years after the reduction, at six to eight years of age, and at the time of the final follow-up.

RESULTS

Lateral growth disturbance of the capital femoral epiphysis was first evident by an average of ten years of age (range, four to fourteen years of age). There was no consistent early pattern of changes in the epiphysis, physis, or metaphysis related to later development of valgus tilt of the epiphysis. Thirty-four hips (59 percent) were rated as satisfactory and twenty-four were rated as unsatisfactory at the latest follow-up evaluation. Hips classified as unsatisfactory exhibited poor acetabular development by an average age of seven years. The inclination of the epiphyseal plate became progressively more horizontal or even reversed over time; however, serial measurements of inclination were not significant predictors of Severin classification.

CONCLUSIONS

Lateral growth disturbance of the capital femoral epiphysis is not necessarily associated with poor acetabular development, as when dysplasia does occur it is generally evident prior to the identification of the physeal arrest. It is important to monitor acetabular development after reduction rather than search for radiographic changes of physeal arrest, which are difficult to detect in young children.

Phosphatidylinositol 3-kinase and mTOR mediate lipopolysaccharide-stimulated nitric oxide production in macrophages via interferon-beta

Bacterial lipopolysaccharide (LPS) elicits responses by macrophages that help the body repel infections. Recent evidence indicates that phosphatidylinositol 3-kinase (PI 3-kinase) may mediate some of these responses. Here, we show that exposing macrophages to LPS rapidly increased membrane-associated PI 3-kinase activity and also elevated p70 S6 kinase activity. Inhibitors of PI 3-kinase or the mammalian target of rapamycin (mTOR) fully blocked p70 S6 kinase activation, implying that this kinase is controlled by PI 3-kinase and mTOR. These inhibitors also substantially reduced LPS-induced nitric oxide (NO) production. This inhibition was, in part, attributable to impaired LPS-stimulated secretion of interferon-beta, an autocrine co-factor for NO production. However, the addition of exogenous interferon-beta did not fully restore NO production, indicating that the NO response was being inhibited by another mechanism as well. Together, these data suggest that PI 3-kinase, mTOR, and possibly p70 S6 kinase mediate LPS-induced NO production by regulating the secretion of interferon-beta and by a second undefined mechanism.

Stress fracture of the hip and pubic rami after fusion to the sacrum in an adult with scoliosis: a case report

Correction of adult scoliosis frequently involves long segmental fusions, but controversy still exists whether these fusions should include the sacrum. It has been suggested that forces associated with activities of daily living transfer the stresses to the remaining levels of the spine and to the pelvis. The case described here was a 43-year-old woman with scoliosis and chronic back pain refractory to non-surgical modalities. Radiographically, the patient had a 110 degree lumbar curve. An anterior and posterior fusion with Luque-Galveston instrumentation was performed. Six months postoperatively the patient returned with a 2-week history of right hip pain with no history of trauma. There was radiographic evidence of a displaced femoral neck fracture and pubic rami fractures. The femoral neck fracture was treated with a total hip replacement. Further surgeries were required to correct a lumbar pseudoarthrosis and hardware failure. We believe that this case provides evidence that fusion into the lumbosacral junction may distribute forces through the pelvic bones and hip resulting in stress and potential hardware complications, especially in patients at risk due to osteopenic conditions.

Stulberg classification system for evaluation of Legg-Calvé-Perthes disease: intra-rater and inter-rater reliability

BACKGROUND

Researchers and clinicians commonly use the classification system of Stulberg et al. as a basis for treatment decisions during the active phase of Legg-Calvé-Perthes disease because of its putative utility as a predictor of long-term outcome. It is generally assumed that this system has an acceptable degree of reliability. This assumption, however, is not convincingly supported by the literature.

METHODS

The purpose of the present study was to assess the inter-rater and intra-rater reliability of the classification system of Stulberg et al. with use of a pre-test, post-test design. During the pre-test phase, nine raters independently used the system to evaluate the radiographs of skeletally mature patients who had been managed for Legg-Calvé-Perthes disease. The intervention between the pre-test and post-test phases consisted of a consensus-building session during which all raters jointly arrived at standardized definitions of the various joint structures that are assessed with use of the classification system. The effect of these definitions on reliability then was assessed by reevaluating the radiographs during the post-test phase.

RESULTS

The pre-test intra-rater reliability coefficients ranged from 0.709 to 0.915, and the post-test coefficients ranged from 0.568 to 0.874. The pre-test inter-rater reliability coefficients ranged from 0.603 to 0.732, and the post-test coefficients ranged from 0.648 to 0.744. Contributing to the variance was a lack of agreement concerning the assessment of joint structures and the way in which the raters translated these evaluations into a classification according to the system of Stulberg et al.

CONCLUSIONS

Although intra-rater reliability was marginally acceptable, the degree of variability between the classifications assigned by different raters even after the intervention - calls into question the reliability of the system of Stulberg et al.; consequently, the validity of any treatment decisions, outcome evaluations, or epidemiological studies based on this system is also in question.

Infantile and juvenile scoliosis

The diagnosis and treatment of scoliosis in the infantile and juvenile age groups is a challenging and demanding endeavor. The diagnosis must be firmly established. Once a deformity has proven to be progressive, surgical intervention will likely be necessary because orthotic treatment is less effective in these cases. The surgeon is then faced with the dilemma of deciding on the most appropriate surgical treatment.

Intra-articular benign osteoblastoma of the acetabulum: a case report

The acetabulum is an unusual location for benign osteoblastoma, usually seen in adolescents and young adults. This article reports a case of an intra-articularly expanding benign osteoblastoma of the acetabulum in a 6-year-old boy. The diagnostic and surgical features of the disease in this unusual location at this young age are discussed. Excisional biopsy and curettage of the lesion followed by bone grafting resulted in healing of the acetabular lesion without acetabular dysplasia, but with a resultant coxa magna.

Atypical congenital kyphosis. Report of two cases with long-term follow-up

We describe two patients with an atypical congenital kyphosis in which a hypoplastic lumbar vertebral body lay in the spinal canal because of short pedicles. There were no defects in the posterior elements, or any apparent instability of the facet joints. Both patients were treated successfully by anterior fusion to the levels immediately above and below the affected vertebra, and posterior fusion which extended one level more both proximally and distally. This gave progressive correction of the kyphotic deformity by allowing some continued anterior growth at the levels which had been fused posteriorly.

Transfusion management in pediatric and adolescent scoliosis surgery. Efficacy of autologous blood

STUDY DESIGN

A retrospective review of consecutive pediatric and adolescent patients who required posterior spinal fusion to correct scoliosis.

OBJECTIVES

To 1) measure the participation of pediatric patients in predeposit programs for autologous and directed blood donation 2) to assess the success of autologous predonation in preventing allogeneic blood use, 3) to determine whether transfusion indications differed between patients who received allogeneic blood and those who received autologous blood, and 4) to assess factors that predict transfusion requirements during scoliosis surgery.

SUMMARY OF BACKGROUND DATA

Authors of recent studies in adults have questioned whether transfusion of autologous blood is a cost-effective therapy when compared with the less-expensive alternative--transfusion of allogeneic blood. In children, the efficacy of autologous blood has not been assessed in a large population of surgical patients. In adults, the frequency of patient participation, the success of autologous donors in avoiding allogeneic transfusion, and the proportion of collected autologous units used during the perioperative period are measures used to establish the efficacy of autologous predonation programs.

METHODS

Hospital and clinic records for each patient who underwent posterior spinal fusion from September 1, 1989 through September 1, 1994 were reviewed. Blood bank consultation, autologous donation records, anesthesia records, surgical reports, and hospital records were reviewed. Seventy percent of patients (164 of 243) participated in autologous donation.

RESULTS

More than 90% of autologous donors successfully avoided receiving allogeneic blood. Patients with idiopathic scoliosis (n = 168) were more likely to participate in autologous donation (n = 144) and to avoid allogeneic blood (n = 135). Patients with neurologic causes of scoliosis more commonly used allogeneic or directed donation (56 of 75 patients). Nineteen patients with neuromuscular causes of scoliosis participated in autologous donation, but more than one half of this group (10 of 19 patients) required allogeneic blood in addition to autologous units.

CONCLUSIONS

Using measures of efficacy similar to those reported in studies of adults, autologous blood was found to be more effective in meeting the transfusion needs of pediatric patients who required posterior spinal fusion than in meeting those needs in adult surgical patients in previous studies.

Spine update. The management of scoliosis in neurofibromatosis

When evaluating patients with neurofibromatosis and scoliosis, a careful search for the evidence of dystrophic changes should done, because prognosis and management depend highly on the presence of these changes. Preoperative imaging studies including computed tomography or magnetic resonance imaging are recommended, especially in cases of dystrophic scoliosis, to detect unrecognized intraspinal lesions. The radiographic findings and the response to treatment in patients with nondystrophic scoliosis are similar to those in patients with idiopathic scoliosis, and the same decision-making process for idiopathic scoliosis is applicable. Careful follow-up evaluation is mandatory, however, because of the tendency for extraordinary progression to occur with growth. Brace treatment of the short, angulated, dystrophic curves is ineffective; early and aggressive surgical intervention is strongly recommended. In most cases, dystrophic curvatures are best treated with combined anterior and posterior spinal arthrodesis. The fusion area should be generous, and the entire structural area of the deformity both anteriorly and posteriorly should be fused.

Natural history and treatment outcomes of childhood hip disorders

Normal hip joint growth and development occur as a result of a genetically determined balance of growth of the acetabular and triradiate cartilages and the presence of a well located centered spheric femoral head. The majority of acetabular development is determined by age 8 years. This is a watershed age for prognosis in many pediatric hip disorders. Hip joint growth and development and how these are affected by the disease process and treatment interventions profoundly affect outcome. Outcomes of these disease processes (congenital hip dislocation and dysplasia, Legg-Calvé-Perthes disease and slipped capital femoral epiphysis), is multifactorial but profoundly influenced by the age at the disease onset (birth to the adolescent growth spurt), and the effects of treatment on the relationship between femoral head and acetabular development. The natural history of many of these childhood hip disorders is the development of degenerative joint disease. Degenerative joint disease and clinical disability may develop in these conditions despite standard up to date treatment interventions. In most of the hip diseases discussed, patients usually do well clinically for many years regardless of treatment.

Long-term psychosocial characteristics of patients treated for idiopathic scoliosis

Psychosocial characteristics of 95 female patients treated with Milwaukee bracing for idiopathic scoliosis were examined using a battery of five psychosocial scales. Sixty-five patients treated with bracing alone and 30 patients who also underwent arthrodesis for curve progression were compared with 49 age-matched female controls. At an average follow-up of 7 years, no differences in depression or health locus of control existed. Significant perceptions of discrimination and a lower satisfaction of overall appearance was recalled during the treatment phase. By final follow-up, there was no longer any difference between the patients and controls in these areas. Significantly, differences in body-image scores persisted at follow-up. Operative patients had a more negative body image of the axial skeleton in comparison with the braced and control groups. We conclude that transient psychological effects are often present during treatment, and a lower body image may persist for several years in surgical patients.

Delayed postoperative paraparesis in scoliosis surgery. A case report

STUDY DESIGN

A case report is presented of an unusual complication of scoliosis surgery that, to the authors' knowledge, has never been reported in the literature.

OBJECTIVE

Neurologic complications can occur after an uneventful posterior spinal instrumentation and fusion for scoliosis. Careful observation during the post-operative period is crucial for early detection of impending neurologic deficit.

SUMMARY OF BACKGROUND DATA

Nerve compression of the cauda equina has been reported as a complication of different types of surgery in the lumbar spine, but an ascending paraparesis has never been described as a complication of scoliosis surgery.

METHODS

A 12-year-old boy with a right thoracic scoliosis measuring 68 degrees and a 72 degrees left lumbar curve underwent Cotrel-Dubousset instrumentation and fusion from T5 to L4. Spinal cord monitoring with somatosensory evoked potentials and motor action potential were recorded and stable through out the entire procedure. Thirty hours later, a rapidly progressive ascending para-paresis developed that required urgent decompression.

RESULTS

This patient underwent urgent decompression and removal of the Cotrel-Dubousset instrumentation. After surgery, the clinical picture improved gradually, and at 2-month follow-up he had regained normal strength in his lower limbs except for a grade 4 left extensor hallucis longus. By 4 months postdecompression, he had made a total recovery.

CONCLUSIONS

Although clinical examination may be difficult to perform in patients who are unconscious, on large doses of narcotic drugs, or mentally retarded, careful observation during the postoperative period and awareness of this complication can allow early detection of impending reversible neurologic deficit and provision of appropriate treatment.

Long-term outcome after open reduction through an anteromedial approach for congenital dislocation of the hip

We reviewed the long-term outcome of open reduction of ninety-three congenitally dislocated hips (in seventy-six children) through an anteromedial approach. The average age of the patients was fourteen months (range, two to fifty months) at the time of the reduction and eleven years (range, four to twenty-three years) at the time of the most recent follow-up evaluation. At the most recent follow-up evaluation, sixty-six hips (71 per cent) had an excellent or good result, twenty-four (26 per cent) had a fair result, and three (3 per cent) had a poor result, according to the Severin classification system. An inverted neolimbus at the time of the operation and postoperative growth disturbance of the femoral head were associated with a poor roentgenographic result. According to the classification of Bucholz and Ogden, twenty-two hips (24 per cent) had type-II avascular necrosis, thirteen hips (14 per cent) had type-III, three (3 per cent) had type-IV, two (2 per cent) had non-classifiable lesions, and fifty-three (57 per cent) did not have avascular necrosis. A high hip dislocation and an operation after the age of twenty-four months were associated with a higher rate of growth disturbances of the femoral head. With the numbers available for study, we did not find any association between short-term preoperative traction, ligation of the medial circumflex vessel, or the type of neolimbus and the prevalence of growth disturbances. Two hips redislocated postoperatively, and seven had transient stiffness. We consider the anteromedial approach to be useful in the management of patients with congenital dislocation of the hip who are twenty-four months old or less. The advantages of this approach include direct access to the obstacles to reduction, avoidance of damage of the iliac apophysis and the abductor muscles, minimum blood loss, the need for only a single operative session for treatment of both hips, and a cosmetically acceptable scar. The prevalence of type-II growth disturbances of the femoral head was higher than had been expected, emphasizing the need for additional investigation.

Traction in developmental dislocation of the hip. Is its use justified?

Traction has been used for decades in the treatment of developmental dislocation of the hip. Traction is advocated to facilitate closed reduction and to decrease the need for open reduction. The use of prereduction traction also is advocated to decrease the incidence of proximal femoral growth disturbance (aseptic necrosis). Recently, several studies have called into question this widely accepted adjunct in the treatment of developmental dislocation of the hip. A critical look was taken at the use of traction in the treatment of developmental dislocation of the hip and whether its use can be justified by the existing medical literature was ascertained. Although there are several impressive reports of the positive effects of traction in developmental dislocation of the hip, there are no clinical or experimental studies on the direct effect of traction. There are also no well controlled studies to analyze the effect of traction as a single variable. Thus, it cannot be proven that traction alters the outcome of developmental dislocation of the hip treatment, and hence, there is only anecdotal basis for its use in the treatment of developmental dislocation of the hip.

All-D-enantiomers of beta-amyloid exhibit similar biological properties to all-L-beta-amyloids

The amyloidogenic peptide beta-amyloid has previously been shown to bind to neurons in the form of fibrillar clusters on the cell surface, which induces neurodegeneration and activates a program of cell death characteristic of apoptosis. To further investigate the mechanism of Abeta neurotoxicity, we synthesized the all-D- and all-L-stereoisomers of the neurotoxic truncated form of Abeta (Abeta25-35) and the full-length peptide (Abeta1-42) and compared their physical and biological properties. We report that the purified peptides exhibit nearly identical structural and assembly characteristics as assessed by high performance liquid chromatography, electron microscopy, circular dichroism, and sedimentation analysis. In addition, both enantiomers induce similar levels of toxicity in cultured hippocampal neurons. These data suggest that the neurotoxic actions of Abeta result not from stereoisomer-specific ligand-receptor interactions but rather from Abeta cellular interactions in which fibril features of the amyloidogenic peptide are a critical feature. The promiscuous nature of these beta-sheet-containing fibrils suggests that the accumulation of amyloidogenic peptides in vivo as extracellular deposits represents a site of bioactive peptides with the ability to provide inappropriate signals to cells leading to cellular degeneration and disease.

Long-term follow-up of Chiari pelvic osteotomy in myelomeningocele

The management of hip instability in myelomeningocele patients is controversial. The purpose of this study is to review our long-term results of isolated Chiari osteotomies in the treatment of hip instability in children with myelomeningocele. Between 1975 and 1988, 11 patients underwent 13 Chiari osteotomies for reducible hip subluxation or dislocation and acetabular deficiency. The patients returned for follow-up clinical examinations, interviews, and radiographs. The average age at the time of surgery was 9.4 years (range, 5-18). The average age at follow-up was 18 years (range, 13-23). The average follow-up was 11.4 years (range, 2-18). The mean preoperative center-edge (CE) angle was -38 degrees. The mean immediate postoperative CE angle was 41 degrees. At final follow-up, the mean CE angle was 4.6 degrees. Only three of the 10 hips had a normal CE angle of > or = 25 degrees. The Chiari osteotomy alone did not achieve long-term hip stability in the majority of patients. Several, if not most, of our patients may progress to frank dislocation with longer follow-up.

The teardrop in congenital dislocation of the hip diagnosed late. A quantitative study

We retrospectively reviewed the radiographs of the pelvis and hips of forty-five patients who had unilateral congenital dislocation of the hip treated with closed reduction and application of a cast without subsequent operations. The radiographs were made at the time of the initial diagnosis, two years after the reduction, when the child was ten years old, and at skeletal maturity. The width, shape, and type of the teardrop; the thickness of the acetabular floor; the acetabular index; the center-edge angle; the articulotrochanteric distance; and the Severin class at maturity were measured in the dislocated and contralateral, normal hips. At the time of the initial diagnosis, a well defined teardrop was seen in thirty-six (80 per cent) of the normal hips and in seven (16 per cent) of the dislocated hips. There was no difference in the width of the teardrop in the seven dislocated hips compared with that in the normal hips, although the v-shaped and crossed types of teardrops were more frequent in the dislocated hips. The v shape was not observed in the normal hips but was seen in sixteen dislocated hips two years after the reduction and in twelve dislocated hips when the children were ten years old. The superior and inferior widths of the teardrop of the dislocated hips were significantly greater than those of the normal hips (p < 0.001 and p < 0.05, respectively) when the children were ten years old. The hips with residual acetabular dysplasia had a v-shaped teardrop, widening of the superior width of the teardrop, and thickening of the acetabular floor. These hips, which were usually Severin class IV at the time of skeletal maturity, had a poor prognosis in adult life.

Activation of multiple proline-directed kinases by bacterial lipopolysaccharide in murine macrophages

Bacterial LPS stimulation of murine macrophages leads to increased tyrosine phosphorylation and activation of the 42- and 44-kDa mitogen-activated protein kinases (MAPK) and the activation of stress-activated protein kinases (SAPK)/c-Jun N-terminal kinase (JNK) and p38, related to the high osmolarity glycerol protein kinase in Saccharomyces cerevisiae (HOG1). LPS caused a rapid increase (10 min) in phosphotransferase activity toward myelin basic protein (MBP), a polypeptide that encompassed the first 169 residues of c-Jun fused to gluthathione S-transferase (GST-c-Jun (1-169)) and 27-kDa heat shock protein (hsp27). MonoQ fractionation of cell extracts resolved phosphotransferase activity peaks toward MBP, GST-c-Jun (1-169), and hsp27, which contained MAPK, SAPK/JNK, and MAPKAPK2, respectively, as indicated by immunoblotting data. In RAW 264.7 macrophages, LPS stimulation of MAPKAPK2, a substrate of p38 HOG1 and MAPK, appeared to occur predominantly via p38 HOG1 and not the MAPK. PMA, which activated the MAPK as potently as LPS, did not strongly activate MAPKAPK2, as assessed by hsp27 phosphorylation. Consistent with p38 HOG1-mediating LPS activation of MAPKAPK2, treatment with LPS, but not PMA, increased the tyrosine phosphorylation of p38 HOG1, a modification known to elevate the enzymatic capacity of this kinase. In LPS-treated cells, the activity of SAPK/JNK was increased 5- to 10-fold, as measured by precipitating SAPK/JNK with Abs or immobilized GST-c-Jun and performing an in vitro kinase assay. In addition, the kinases thought to be upstream of SAPK/JNK, SAPK/ERK kinase 1 (SEK1), and MAPK/ERK kinase kinase 1 (MEKK1), were activated following LPS, but not PMA, exposure (5-fold and 2.5-fold, respectively.

Activation of multiple proline-directed kinases by bacterial lipopolysaccharide in murine macrophages

Bacterial LPS stimulation of murine macrophages leads to increased tyrosine phosphorylation and activation of the 42- and 44-kDa mitogen-activated protein kinases (MAPK) and the activation of stress-activated protein kinases (SAPK)/c-Jun N-terminal kinase (JNK) and p38, related to the high osmolarity glycerol protein kinase in Saccharomyces cerevisiae (HOG1). LPS caused a rapid increase (10 min) in phosphotransferase activity toward myelin basic protein (MBP), a polypeptide that encompassed the first 169 residues of c-Jun fused to gluthathione S-transferase (GST-c-Jun (1-169)) and 27-kDa heat shock protein (hsp27). MonoQ fractionation of cell extracts resolved phosphotransferase activity peaks toward MBP, GST-c-Jun (1-169), and hsp27, which contained MAPK, SAPK/JNK, and MAPKAPK2, respectively, as indicated by immunoblotting data. In RAW 264.7 macrophages, LPS stimulation of MAPKAPK2, a substrate of p38 HOG1 and MAPK, appeared to occur predominantly via p38 HOG1 and not the MAPK. PMA, which activated the MAPK as potently as LPS, did not strongly activate MAPKAPK2, as assessed by hsp27 phosphorylation. Consistent with p38 HOG1-mediating LPS activation of MAPKAPK2, treatment with LPS, but not PMA, increased the tyrosine phosphorylation of p38 HOG1, a modification known to elevate the enzymatic capacity of this kinase. In LPS-treated cells, the activity of SAPK/JNK was increased 5- to 10-fold, as measured by precipitating SAPK/JNK with Abs or immobilized GST-c-Jun and performing an in vitro kinase assay. In addition, the kinases thought to be upstream of SAPK/JNK, SAPK/ERK kinase 1 (SEK1), and MAPK/ERK kinase kinase 1 (MEKK1), were activated following LPS, but not PMA, exposure (5-fold and 2.5-fold, respectively.

Activation of c-Jun N-terminal kinase in bacterial lipopolysaccharide-stimulated macrophages

Activation of macrophages by bacterial lipopolysaccharide (LPS) induces transcription of genes that encode for proinflammatory regulators of the immune response. Previous work has suggested that activation of the transcription factor activator protein 1 (AP-1) is one LPS-induced event that mediates this response. Consistent with this notion, we found that LPS stimulated AP-1-mediated transcription of a transfected reporter gene in the murine macrophage cell line RAW 264.7. As AP-1 activity is regulated in part by activation of the c-Jun N-terminal kinase (JNK), which phosphorylates and subsequently increases the transcriptional activity of c-Jun, we examined whether LPS treatment of macrophages resulted in activation of this kinase. LPS treatment of RAW 264.7 cells, murine bone marrow-derived macrophages, and the human monocyte cell line THP-1 resulted in rapid activation of the p46 and p54 isoforms of JNK. Treatment with wild-type and rough mutant forms of LPS and synthetic lipid A resulted in JNK activation, while pretreatment with the tyrosine kinase inhibitor herbimycin A inhibited this response. Binding of LPS-LPS binding protein (LBP) complexes to CD14, a surface receptor that mediates many LPS responses, was found to be crucial, as pretreatment of THP-1 cells with the monoclonal antibody 60b, which blocks this binding, inhibited JNK activation. These results suggest that LPS activation of JNK in monocyte/macrophage cells is a CD14- and protein tyrosine phosphorylation-dependent event that may mediate the early activation of AP-1 in regulating LPS-triggered gene induction.

Use of the Milwaukee brace for progressive idiopathic scoliosis

One hundred and two (92 per cent) of 111 immature patients in whom idiopathic scoliosis had been treated with a Milwaukee brace were followed to determine the effectiveness of the brace in preventing progression of the scoliosis. The average time from cessation of bracing until the latest radiographs were made for the patients who were managed non-operatively was six years and four months. The average progression of the curve, from the time of initial bracing until use of the brace was stopped, in the eighty-eight patients who were included in the statistical analysis was 4 degrees. The curve continued to progress an average of 5 degrees after use of the brace was stopped in the patients who did not have an arthrodesis. Forty-two patients (48 percent) had more than 5 degrees of progression at the time that use of the brace was stopped. Thirty-seven patients (42 per cent) had an operation or a curve of sufficient magnitude to warrant operative intervention. The maximum correction of the Cobb angle in the brace had prognostic importance for progression of the curve. The patients in whom the curve did not progress or who did not need operative intervention had had an average correction of 20 per cent, while the patients who had a failure had had an average correction of 8 per cent. The patients who eventually had the indications for an arthrodesis were on the average, one year younger (eleven years and none months) and had a curve of a larger magnitude at the time of bracing than the patients who did not need an arthrodesis. The findings of this study do not agree with previously reported favorable results with bracing and raise questions about whether the natural history of progressive idiopathic scoliosis is truly altered by use of the Milwaukee brace.

Natural history of untreated chronic slipped capital femoral epiphysis

From 1915 to 1952, 31 hips in 28 patients with slipped capital femoral epiphysis were observed without interventional treatment at the University of Iowa Department of Orthopaedic Surgery. A slip was considered chronic if the symptoms had been present for 3 weeks or more. The severity of the slip was determined by radiographs. Assessment included Iowa Hip Rating and grading of radiographic degenerative changes. The mean duration of patient followup from the onset of symptoms was 41 years. The mean patient age was 54 years old at review, and 13 years old at onset of symptoms. Degenerative arthritis developed in hips with displaced slipped capital femoral epiphysis. Untreated slipped capital femoral epiphysis can progress to a severe degree. The natural history of chronic slipped capital femoral epiphysis is favorable provided that displacement is minimal and remains so.

Radiologic pelvic asymmetry in unilateral late-diagnosed developmental dysplasia of the hip

Eighty-three cases of unilateral late-diagnosed (older than 4 months of age) developmental dysplasia of the hip (DDH) were studied to evaluate pelvic shape and innominate bone relationships in the initial anteroposterior radiograph. To be included, each initial radiograph had to have no lumbar pedicle rotation, lumbar scoliosis, gas shadows, or metallic protectors. Measurements were done using as reference a medial pelvic line, which divides the pelvis into two innominate bones. Lineal parameters were defined to assess pelvic radiologic shape; angular parameters defined the relationship between the ilium, ischium and pubis, and sacrum. Statistically significant differences were observed in most cases, and pelvis asymmetry was evident. The asymmetry was more obvious in cases in which the teardrop had a negative value and in low dislocations. Similar changes have been observed in experimental dislocation of the hip secondary to a triplane pelvic deformity. We suggest that similar alterations of pelvic shape occur in DDH, possibly secondary to growth disturbance in the triradiate cartilage.

Packed red cells in acute blood loss: dilutional coagulopathy as a cause of surgical bleeding

The purpose of this study was: 1) to define coagulation abnormalities in patients who receive red cell concentrates rather than whole blood for large volume blood loss (greater than 0.5 blood volume); and 2) to determine when coagulation abnormalities lead to increased bleeding in the massively transfused surgical patient. We studied 32 ASA physical status I or II patients (mean age 15.6 +/- 2.3 yr) who lost more than 50% of their blood volume during elective posterior spinal stabilization. Crystalloid solutions and packed red cell concentrates were used to replace blood and fluid losses. Invasive hemodynamic measures, urinary output, and serial hematocrit determinations were used to help maintain a constant intravascular volume and confirm the estimates of blood loss. The quality of hemostasis was assessed during operation. In 15 of the 32 patients, surgical hemostasis remained effective throughout posterior spinal fusion. A coagulation profile (prothrombin time [PT] and activated partial thromboplastin time [aPTT], platelet count, and fibrinogen) was measured at the conclusion of operation in these patients. In 17 patients, increased surgical bleeding as a result of decreased clot formation and increased bleeding from the wound was present. In these 17 patients at the time increased bleeding was diagnosed, hemostatic tests (PT, aPTT, fibrinogen, platelet count, and coagulation factor assays V, VIII, and IX) were obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic stress tolerance levels for human articular cartilage: two nonuniform contact models applied to long-term follow-up of CDH

Two computer models of nonuniform contact stress on the articular surface of the human hip were used to study the relationship between chronically excessive articular cartilage contact stress and long-term clinical outcome in a series of patients with congenital dislocation of the hip (CDH). The analyzed database consisted of 409 stylus digitized radiographs from 83 patients with unilateral CDH, who had been treated by closed reduction, and whose average follow-up time was 29.2 y. The first model (nonuniform Legal) involved a three-dimensional contact stress distribution function whose pole was coincident with the resultant force acting through the hip, and which acted over a contact area whose borders were determined soley by bony landmarks. In the second model (Brinckmann), the direction of the pole of the contact stress distribution function was initially unknown; one border of the contact region was determined by radiographic landmarks, while the other border depended upon the pole of the iteratively determined contact stress distribution function. In both models, the contact stress distributions were converted to area engagement histograms, corresponding to the fractional areas of cartilage experiencing specific ranges of stress (0.5 MPa increments). These histograms were integrated over time to calculate a cumulative contact stress overdose, which was then compared to clinical outcome. Reasonable correlations (Spearman rho = 0.63-0.66) with patient outcomes were obtained for optimally chosen damage thresholds, although these thresholds were appreciably different (2.0 versus 4.5 MPa) due to the respective modelling assumptions.